Robotic Hybrid Manufacturing by Mohamed Owaze Ansari

STUDIO III

Master in Robotics and Advanced Construction 2018-2019 STUDENTS: SEBASTIAN VOIGT | OWAZE ANSARI | SUBHASH PRAJAPAT | APOORV VAISH FACULTY: ALEXANDRE DUBOR | ALDO SOLLAZZO

ACKNOWLEDGEMENT Our team wants to say thanks for all the support we got from the professors and other faculty members from IAAC to have the freedom to develop our project and bring it to the level we reached at the end of this final term. Special thanks to all our families and friends supporting us in our idea and giving us the space, time and trust to develop our idea and bringing our final project to the state it finally has..

ROBOTIC HYBRID MANUFACTURING

Hybrid Manufacturing combines two or more established manufacturing processes into a new combined set-up whereby the advantages of each discrete process can be exploited synergistically. (2010, CIRP - International Academy of Production Engineering)

TABLE OF CONTENT

INTRODUCTION……………………………………………….………………………………………….. 8 TYPES OF HYBRID MANUFACTURING……………………………………………….……. 13 ADDITIVE VS. SUBTRACTIVE…………………………………………………………..... 14 WORKFLOWS……………………………………………….…….……………………………………….. 17 ROBOT VS. CNC-MACHINE…………………………………………………………......... 18 Introduce as conclusion of robot vs cnc……………………………………………………… 20 FRAMEWORK……………………………………………….……………………………………………… 21 BIG SCALE - CNC…………………………………………………………............................ 22 BIG SCALE - ROBOTIC………………………………………………………….................. 23 3D-PRINTING……………………………………………….………………………………………………. 25 Physical Properties of FDM…………………………………………………………........... 26 HYBRID MATERIALS……………………………………………….…………………………………… 29 THERMOPLASTICS……………………………………………….…………………………………….. 33 RECYCLED THERMOPLASTICS……………………………………………….………………… 37 HYBRID TOOL……………………………………………….……………………………………………… 43 CONCEPT……………………………………………….……………………………………………………... 47 GENERATIVE DESIGN………………………………………………………….................... 51 ALGORITHMIC DESIGN…………………………………………………………................. 52 TOPOLOGY OPTIMIZATION…………………………………………………………......... 54 HYBRID DESIGN………………………………………………………….............................. 56

FABRICATION PROCESS……………………………………………….………………………...... 59 MOLD FABRICATION: Milling……………………………………………………………………... 60 MOLD FABRICATION: Assembly ……………………………………………………………….. 61 3D-PRINTING ON A MOLD : SURFACE COAT…………………………………………. 62 LAYER 1: ALGORITHMIC DESIGN………………………………………………………. 67 LAYER 2: SPIRAL DESIGN…………………………………………………………............ 68 MILLING………………………………………………………….............................................. 70 ADDONS……………………………………………….………………………………………………………. 73 SENSING………………………………………………………………………………………………………… 75 AUTOMATED PATH PLANNING BY AI……………………………………………………… 76 CUSTOMISED PATH PLANNING………………………………………………………………… 77 SCANNING: PHOTOGRAMMETRY…………………………………………………………….. 78 TACTILE SCANNING …………………………………………………………………………………... 79 APPLICATIONS……………………………………………….……………………………………………. 80 AEROSPACE INDUSTRY………………………………………………………….... 3D PRINT AN ENTIRE ROCKET IN 60 DAYS……………………………………………. 82 3D printing could reduce airplane's weight by 4 to 7 percent………………… 83 3D printed economy class seat / Mass customisation……………………………… 84 ARCHITECTURE………………………………………………………….... 3D PRINTED URBAN STRUCTURES…………………………………………………………. 85 3D PRINTED HOUSES AND PANELS………………………………………………………... 86 MOLDS…………………………………………………………………………………………………………... 88 3D PRINTED MODELS…………………………………………………………………………………. 89 AUTOMOTIVE PROTOTYPING: FOAM+CLAY MODELS………………….. 90 FUTURE……………………………………………….………………………………………………………... 91

INTRODUCTION Hybrid Manufacturing, as in our case, it is simply the senseful combination of subtractive methods like cnc-milling and additive methods like 3D-printing in a fabrication system, has still reached the market in the metal industry. Other industries, handling with custom big scale 3d shapes, still try to improve fabrication speed, waste reduction or surface quality by focusing on just producing with one of these methods. The combination of both methods together with a robotic system with a greater freedom of movements and reachability could save time and waste and increase the quality and accuracy of big scale objects. The freedom of a subtractive and additive process in one setup could also create the possibility of producing designs which where not feasible to produce before. Furthermore materials are needed which are hybridable, means they could be milled and also 3d-printed. In that case, thermoplastics, which are thrown as non compostable waste in a landfill are now the most interesting material for hybrid manufacturing. This project is trying to reactivate the interest to thermoplastics as an important resource for creating a new kind of manufacturing big scale products. This project tries to point out the economical relevance of a possible regional robotic setup, for fast production between unique and mass product.

WHY ?

Image Source: Kiotec Group

WHY As Designers, Architects, Engineers we get more and more advanced software based tools in the hand to develop the future of how we live , where we live and how the shapes of the future would look like. We also talk a couple of decades about customization in terms of â&#x20AC;&#x153;mass customizationâ&#x20AC;? but this is mostly just a combination of different parts of the same mass produced product. We are still addicted to the mass production and big companies ruling the market. With the industrialisation we got plastics, which changed the way we handle objects. And now we throw them away as landfill and created a big ecological problem out of it. We discovered a new way to get use of robotics used in the automotive industry but it still didn't found the way out of mass producing companies. We have 2 prototyping methods which are used to create complex shapes but both have his very own issues. Combining all these facts in a robotic hybrid manufacturing system we think we can create a new kind of manufacturing complex shapes in a closed material loop system much more material and time efficient and we can close the economic gap between production of unique pieces and mass production.

BUSINESS FIELDS We have complex shapes nearly everywhere in our lives and besides the mass production industrie a wide range of business fields who could be very interested in the potential of hybrid manufacturing.

PROTOTYPING

AUTOMOTIVE INDUSTRIE The automotive industry is mostly making their molds for prototyping out of a milled foam block and a clay coating on top which ist processed manually or milled again by a CNC-machine. But the coating process is mostly done by manual labour . That takes time and money and could be automated by HM . Also the inner Styrofoam core could be avoided by printing a stable wall instead. MOVIE INDUSTRIE Creating futuristic movies means shaping the future superlatively in case of props . These props should show how the future could look like and the props are unique products which were never produced before. Time and money are very important in the movie industry and to find smarter solutions for these two issues and creating a setup which could produce a wide range of different novel shapes is a necessity besides the growing digital production. ARCHITECTURE For architecture it's crucial to find a way to produce a high amount of unique big shapes, matching together in a much bigger scale. So moldmaking could be quite interesting . PRODUKTDESIGN Finding new shapes , testing new designs and functions is an important part of product design and a tool which could give the possibility to test designs not only in the right scale but also in the right surface finish and physical behavior could help for decision making but it also gives the possibility to create small series of products besides the mass production industry and brings the designer even closer to the end user.

PROPS

MOLDMAKING

SMALL SERIES

TYPES OF HYBRID MANUFACTURING

Image Source: Trumpf Laser Metal Deposition (LMD)

It seems like we reached the era of 3DPrinting were more and more companies rise up developing new kind of 3dprinters, bigger, faster or with complete new materials. But one thing stays mostly always the same. The printed layers are nearly always visible for the human eye . Good engineered machines could decrease the layer height to microns but that affects the fabrication time or the size of the object. So talking about big scale additive manufacturing we could wether take the visible lines as a design statement or we have to find ways to get rid of them . But 3D-Printing gives also the freedom to produce forms which were impossible or very difficult for cncmilling . It is also a forceless fabrication method and much easier to program compared to cnc-milling strategies. The future definitely belongs to 3dprinting but besides improving the machines and processes we also have to find feasible solutions on the way

VS.

ADDITIVE

ADDITIVE SUBTRACTIVE

ADDITIVE VS. SUBTRACTIVE

SUBTRACTIVE CNC-milling is a well established fabrication method for prototyping out of a wide range of materials as well as fabricating parts with a high accuracy for the industry as mass production tool. It is one of the most precise fabrication method and is used for big scale as well as production of small pieces. But the disadvantage of CNC-milling is that mostly by fabricating complex freeform shapes, much material is wasted because the prefabricated materials are coming in standardized shapes . That also affects the millingtime and the wear and tear of the tools. It also needs much programming effort to get to the final shape. COMBINATION So the combination of both methods could be very senseful . Mostly the advantage of the one is the disadvantage of the other. So by combining both we can get all the advantage and getting rid of all disadvantages .

Image Source: Warping, 3dhubs Image Source: Nital, Nagami: Manuel JimĂŠnez GarcĂa

ADVANTAGES

CNC ROUGHING

We can create parts with walls via 3Dprinting instead of full volumes like in CNC-milling . We can also create inner structures with the advantage of 3Dprinting . Much amount of material will be saved and milling waste can be looped back and used for 3D-printing. So we can create a closed material loop without wasting material.

ROUGH PRINTING

We can create high accuracy parts with trusted accuracy for connection points and fittings. We can get rid of the visible printing lines and get a high quality surface finish close to injection molded parts. We can decrease the production time by using rough printing instead of rough milling .

CNC FINISHING

We can repair things instead of throwing them away and we can always correct while fabricating using both methods together.

Image Source: Stratatys Direct

17 Image Source: Milling, Sreeyantra IN

HYBRID

Types of hybrid manufacturing

TYPES OF MANUFACTURING

Having 2 methods in one setup which are based on additive and subtractive methods we have the freedom to combine these in different ways. According to the shape and function of the piece which should be manufactured we consider the decision between AM and CNC translates from a binary workflow to a more continuous workflow where we can choose the most efficient way of producing by combining both methods.

The different types or workflows of hybrid manufacturing depend on the particular application which it is planned for. It could be driven by time efficiency as well as reducing the amount of material . But also novel dimensions are coming now in the field of view. It could improve structural properties or new kind of designs which where not possible with just using on of these both methods.

3D-Printing + Milling

Milling + 3D-Printing + Milling

This could be one of the most important economical proofs of hybrid manufacturing. Instead of roughing a big amount of material out of a big stock to create a model out of, 3Dprinting can be used for a rough-printing. This intermediate step before the final milling finish can save a lot of material and time .

â&#x20AC;&#x153; By having these both methods you have always the tool to correct the errors of the previous without any human interaction . â&#x20AC;&#x153;

3D-Printing + Milling + 3D-Printing â&#x20AC;Ś

This is the method we describe later as our proof of concept. We are milling a mold with the robot to print directly on that mold. We try to print very rough, fast and with a advanced printing strategy supporting the tensile strength of the object we want to create. Afterwards we mil again over the surface to get a nice surface finish without visible printing-lines and for accurate outline dimensions and accurate working areas for the connection of other attachment parts. This method is probably the most effective in terms of producing small series of products or prototypes and gives also the possibility to brake out of the planar layer printing to the idea that we can create the physical layers over and over again and always different . Because 3d-printing just needs any surface and didn't care if it is straight, uneven or a freeform.

Milling + 3D-Printing This combination could be useful to let the milled part work like a mold for the 3D-printing process of a specific shape or to use the 3d-Print as a kind of coating on top of structural inferior materials

This method is often used in the metal industry where a part is first printed and then milled accurate and on top of that another 3d-print is attached to get milled again. It could be seen as a close loop. And this shows the big benefit of combining both methods over and over again to find new ways of structural improvements as well as a new way to fabricate parts which were difficult to fabricate before.

Image Source: Ethereal Halo

Milling + 3D Printing

Image Source: Hybrid Manufacturing Technologies, US

3D Printing + Milling

WORKFLOWS 3D Printing + Milling + 3D Printing ...

Image Source: Hybrid Manufacturing Technologies, US

Milling + 3D Printing + Milling

ROBOT VS. CNC-MACHINE

For big scale hybrid manufacturing are two different machine setups practicable. One is the CNC-machine working in a closed frame with a numerical control . They are controlled by GCode and MCode. 3D-Printers and Milling-machines are mostly CNC-machines working with stepper or servo-motors. In both methods, the machines are very precise depending on the quality of the construction and the motors. Also in a big scale CNC-machines are very accurate and used for CNC-milling operations for example in the automotive industry. The other machine setup is the robot arm, normally used in the automotive industry for repetitive tasks like pick&place operations. In terms of automation tasks the robots are quiet accurate (under 1mm ) but in terms of motion, means moving on a giving path perfectly like CNC-machines do is very difficult for robot arms. A robot is working with inverse kinematics trying to follow a path in the TCP (Tool center point ) by informing all his joints to rotate in the right angle and direction. But the are still used for additive manufacturing and CNCmilling but with less accuracy then typical CNCmachines . But therefore with much more degrees of freedom and the ability to reach every point in the robot range out of different directions . And also robot companys like Kuka have still noticed these new fields for ther robots and developed a motion package called Kuka.CNC with much more accuracy in motion on a path working with standard CNC-Code. + + + +

6-Axis Freedom and more if needed Costs around 200.00 â&#x201A;Ź Needs less space than a CNC-machine Community of developing endeffectors and software for parametric control and more

Less Accuracy then rigid CNC-machine more experimental and mostly not available as a full package out of the right hardware and software . Image Source: KUKA Systems

Both setups have advantages and disadvantages and it depends on the specific business case which machines would be the better choice. Is more accuracy needed or more the freedom of axis ? A big advantage of the robot is that it is a multipurpose machine and is able to make completely different tasks according to the mounted tool and therefore its probably the better machine for research into new fields of fabrication. A CNCmachine on the other side is mostly a closed system with no access to manipulate or change the given tools . A CNC-machine is mostly a complete package out of hardware and software working together in a perfect manner. But it will soon happen that the robot accuracy gets better and better and also companies arise, which build working robot end-effectors together with the right software to run thousand of different senseful applications for a robotic arm.

+ + +

High accuracy Hardware and Software are well aligned Easier access in fabrication process

Costs around 500.000 â&#x201A;Ź and higher Much space needed Less axial freedom then robot

Image Source: Zimmermann

Introduce as conclusion of robot vs cnc

The contextual framework of our project is the connection of a couple of different important values. We found few companies tackling one or more of these values, but none of these companies or projects tackle all of the values. All these companies came up in the last couple of years and are successfully working in his specific field. They show the wide range of business fields for hybrid manufacturing, big scale 3d-printing, real 3d-printing (Multi-Axis-Additive-Manufacturing) and the use of thermoplastics. Just the metal industry currently working in the field of hybrid manufacturing. A few of the other shown companies could improve their market value by adding hybrid manufacturing to their work range.

FRAMEWORK

Image Source: AI-Build, London

BIG SCALE - CNC

BIG SCALE - ROBOTIC

Project

Big-Scale

BAAM-CINCINNATI

BIGREP

METAL INDUSTRY

KAMERMAKER

ZAHA-HADID - THALLUS

DIRK VANDER KOOIJ

KRAKEN

MATAERIAL

RELATIVITY SPACE

EMBEDDED 3DP (MIT SELF-ASSEMBLY LAB)

LASSIM PROJECT

BRANCH TECHNOLOGY

MX3D

ETHEREAL - HALO ROBOTIC HYBRID MANUFACTURING

>3-Axis AM

Thermoplastics

Robotic Arms

Hybrid (Milling+AM)

X X

3D-PRINTING

Image Source: Pinterest

Injection molding is the most used mass production method for forming thermoplastics into shape. In this process hot liquid thermoplastics are shot into a injection mold and are cooled down before they were released out of the mold. This process besides thermoforming are the best for the physical performance of the produced parts out of thermoplastics. 3d-printing is mostly based on linear extrusion in a XY-matrix and stacked in Zlayers. The adhesion between the extruded lines are in XY-direction as well as in Zdirection based on the overlap between the printed paths. Liquid new material is printed over cooled down already printed paths and they connect to each other but the connection is not as stable as in solid parts made out of injection molding machines.

“The lower strain can most likely be attributed to the internal structure of the parts. Compared to AM processes, injection molding typically has lower porosity and greater homogeneity, leaving fewer imperfections in the structure of the material to encourage crack propagation. “ Research Credit: Matthias Fischer and Stefan Josupeit from DMRC (Direct Manufacturing Research Center)

MULTI-DIRECTIONAL LAYER PRINTING

PHYSICAL PROPERTIES OF FDM

Physical Properties of FDM (Fused Deposition Modeling )

For 3d-printing an object we have to notice that the printing orientation is crucial for the tensile strength . A side overlap whether its in XY-direction or in Z-direction has less tensile strength than the printing path itself. The solution for the XY-overlap is to rotate the printing paths on the next layer to get a cross-shaped stable compound .

Researchers found out that 3d-printed parts made with FDM could withstand a force of up to 148 MPa in XY-Direction and in ZDirection as well as in every 2-dimensional overlap up to 40 MPa. Researchers at DMRC generated standard stress-strain curves to compare the stresses of FDM with traditional injection molded parts. They found out that : “The FDM part printed in the X-direction performed equivalently to the injection molded part in stress, but fractured at a much lower strain. “

But printing traditionally in 2.5D, that means printing on an XY-Plane and in Z-Layers gives us certain limitations in producing physically comparable objects to injection molded ones. So we are orienting the parts according to the best possible performance of the tensile strength we need for the object we want to produce.

In this method we have to different approaches. We have antigravity printing which works in terms of thermoplastics just until a specified degree of overhang-angle and path-length and in terms of metal with much less restrictions. This is priority used for lattice structures in a robotic setup for making fast and stable support or formwork structures with thermoplastics as well as with metals.

MULTI-PLANE PRINTING One solution could be to change the printing planes while printing from XY to XZ or YZ to create a crossshaped compound in every possible dimension. A research paper from Ismayuzri Bin Ishak from 2013 is tackling the topic : â&#x20AC;&#x153;Robot FDM Platform for MultiPlane and 3D Lattice Structure Printing â&#x20AC;&#x153; . He is calling this process Multi-Layer-printing. In his research paper he was testing if a multi-plane layer printing could affect the tensile strength of the 3d-printed parts. As conclusion of all of his tests he could increase the tensile strength as well as the yield strength and the modulus of elasticity of his 3dprinted parts . According to the desired mechanical properties of 3dprinted parts multi-layer printing gives a added value getting a step closer to the physical properties of injection molded parts. For this advanced 3d-printing strategy most of the 3axis based 3d-printers are not working and at least a 4-Axis machine is needed. MULTI-AXIS PRINTING The next iteration of 3D-printing strategies following is the translation of printing on a two-dimensional layer in just two axis to a multi-axis printing acting simultaneous in all 3-axis of a 3d-space (XYZ). Instead of dividing every model in planar slices to create the printing layers, we can create layers based on the specified surface of each object. Image Source: Mataerial, IAAC

By combining all different printing strategies in a process with the freedom of a robotic arm , 3d-printed structures could be created with good structural behavior , fast and with a novel freedom of fabricating parts .

PHYSICAL PROPERTIES OF FDM

Curved, double-curved and freeform surfaces could be produced more efficient while the created printing paths are following the particular shapes .

The other method is 3d-printing on a mold or any already existing surface. This shape defines the shape of the printed surface.

HYBRID MATERIALS

Image Source:Digital Stereotomy, University of Toronto

METAL

THERMOPLASTIC

Metal 3D printing processes can be used to manufacture complex, bespoke parts with geometries that traditional manufacturing methods are unable to produce. Metal 3D printed parts can be topologically optimized to maximize their performance while minimizing their weight and the total number of components in an assembly.. Metal 3D printed parts have excellent physical properties and the available material range includes difficult to process otherwise materials, such as metal superalloys.The material and manufacturing costs connected with metal 3D printing is high, so these technologies are not suitable for parts that can be easily manufactured with traditional methods.The build size of the metal 3D printing systems is limited, as precise manufacturing conditions and process control are required. Already existing designs may not be suitable for metal 3D printing and may need to be altered.

Fused Deposition Modeling (FDM) of Thermoplastics offers a wide variety of polymers, from ABS to polyphenylsulfone (PPSF), in order to provide engineeringgrade materials in a 3D printing process. FDM thermoplastics offer special qualities, such as electrostatic dissipation, translucence, biocompatibility, VO flammability and FST ratings. These robust materials make FDM a viable option for functional prototyping and production parts in aerospace, automotive and medical industries. FDM can also affect a partâ&#x20AC;&#x2122;s elastic modulus, elongation at break and flexural strength. With careful design considerations, these differences may not be significant for some applications.Each FDM material is dimensionally stable and durable enough for demanding applications. The easiest way to identify the right FDM thermoplastic would be to consider the partâ&#x20AC;&#x2122;s characteristics, support material type and color.

TPU is a product that delivers a set of unique characteristics. It has rubber-like elasticity, which distinguishes it from the more common ABS and PLA. It is also resistant to abrasion, and has been shown to perform well even at low temperatures. TPU has generally been used to print products that need to bend or flex during application, such as sporting goods, medical devices, footwear, inflatable rafts, outer cases for mobile devices, and automotive instrument panels. It has also been used for industry applications due to its resistance to oils, greases, and a variety of solvents.The main drawback in using flexible filaments such as TPU is the extra challenge in handling them during printing. As we mentioned, not all 3D printers are equipped to use flexible filaments. Printers that use Bowden extruders are particularly problematic.

TPU

As soon as the metal industry noticed metal 3d-print as chance for a new kind of production, they figured out that the quality of 3d-printed parts didnâ&#x20AC;&#x2122;t correspond to their quality needs. Instead of decreasing the layerheight of the 3d-printed parts with a increased printing time, they started combining a rough and fast material deposition with cnc-milling to get the needed resolution and surface accuracy. A couple of companies are still specialized in metal hybrid manufacturing also advertising the repair of high value metal parts and addition of features onto existing parts and billets.

Image Source: Hybrid Manufacturing Technologies, US

A handful of companies and researches are showing hybrid processing of 3d printed thermoplastic parts by milling over the visible lines of the printed surface to reach a high surface finish as well as printing on pre-milled parts to print on top of them. But these test are still in a very small scale in a CNC-machine.

Image Source: Hybrid Manufacturing Technologies, US

Within the so called Futurecraft.Loop Adidas just released a shoe which could be recycled to 100 % which is based on just one particular material. With the use of this thermoplastic polyurethane (TPU) adidas promises a new kind of production where shoes can be send back to the manufacturer after a lifecycle and will be recycled to a complete new shoe.

Image Source: Futurecraft.Loop, Adidas

Thermoplastics are suitable for hybrid-manufacturing as they represent cradle-to-cradle materials which can be used, recycled and reused again. The waste produced through the subtractive manufacturing could be reused. In the future, materials like TPU could be adopted in industries as a zero-km material birthed and rebirthed in the same pace. In the grand scheme, products can be mass-customized using hybrid-manufacturing, later scrapped at the end of their lifecycle, to be recycled and fabricated into a new product.

THERMOPLASTICS

Image Source: Unknown

THERMOPLASTIC : Thermoplastics are the plastics that can be recycled. Thermoplastics can be melted back into liquid and moulded multiple times.

1. PET (polyethylene terephthalate) This is a very strong plastic that can be easily recognised for its transparent look. All beverage bottles are PET. This plastic is also used in many other products like jars, combs, bags, tote bags, carpets and ropes. Items made from this plastic are commonly recycled. Most recently, PET is often recycled into yarns to make clothes. This plastic is a bit more complex to work with after recycling. 2. HDPE (high-density polyethylene) This plastic is often used for food or drink containers. Items made from this plastic include containers for milk, motor oil, shampoos, soap bottles, detergents, and bleaches. Many toys are also made from this plastic. This plastic works very well with recycling process.. 3. PVC (polyvinyl chloride) This is toxic and not recommended to work with it. PVC is most commonly found in plumbing pipes and releases chloride when heated up. Do not use with recycle and printing. 4. LDPE (low-density polyethylene) Plastic wrap, sandwich bags, squeezable bottles, and plastic grocery bags all are made from LDPE. Usually, LDPE is not recycled from the industry but works rather good with recycle Plastic.

Image Source: Unknown

Types : Thermoplastics are further grouped in seven different subcategories often referred to as plastic types. Each plastic type has its specific chemical composition, properties and applications and is given a specific number, called SPI code to differentiate between them. Today, most manufacturers follows this coding system and place the SPI code on their products. This will tell us its melting temperature so that we can set machines at the correct temperature and run a smooth recycling process. The different plastic types are:

5. PP (polypropylene) This is one of the most commonly available plastic on the market. This type of plastic is strong and can usually withstand higher temperatures. Among many other application, it is consistently used for products that get in contact with food and drink (Tupperware, yoghurt boxes, syrup bottles etc..). PP works very well with recycle Plastic. 6. PS (polystyrene) PS is most commonly known as Styrofoam. PS can be recycled, but not efficiently; recycling it takes a lot of energy, which means that few places accept it. Disposable coffee cups, plastic food boxes, plastic cutlery and packing foam are made from PS. Very good to work with recycle Plastic. 7. Other (Mix) This code is used to identify other types of plastic that are not defined by the other six codes. ABS, Acrylic or Polycarbonate are included in this category and can me more difficult to recycle. Mixing plastic Different plastic types should never be mixed together when working with recycle Plastic as this will make it impossible to recycle them again. Mixing plastics would end their cycle. Moreover, when different types of plastics are melted together they tend to phase-separate, like oil and water, and set in layers resulting in structural weakness and lower quality products.

Source : https://www.simplify3d.com/support/materials-guide/properties-table/

PP.

PET

LDPE

HDPE.

PLA.

ABS

RECYCLED THERMOPLASTICS

Image Source: Precious Plastic.

Image Source: Precious Plastic

RECYCLING : Collection of material Generally all sort of plastic are gathered into a single place for further treatment but for this project we have collected following waste plastic 1. Domestic products such as coffee plastic cover, for that we have maintained a collection bag (with appropriate signage) inside of the classroom for people to drop waste Plastic. 2. Plastic Crates (HDPE, LDPE & PP) 3. 3d Printers Waste

Cleaning and Drying The collected plastics were sorted and separated into HDPE, LDPE and PP. This categorisation was performed to ensure proper process and avoid contaminant along the way for further post-processing. For cleaning the plastic, we put it in warm water to remove the dirt and afterwards, we put them to dry for some time.

Shredding and Filtering The plastic shredder was used to shred the material into recyclable material. Similar plastic was shredded together and the mixed plastic together to obtain the flakes that will be used 3d printing. Some of the big plastic crates was unable to fit in the shredded and was cut with hacksaw machine to reduce its size to enable the fitting.

The shredder works by throwing the plastic through a hopper into the shredder that cuts the plastic into recyclable material (flakes). The flakes are collected through a 5mm filter located at the bottom of the shredder to get an approximate uniform flake size.

RECYCLING

Injection Machine The granulation process with recycled HDPE flakes are produced to sausages using the injection machine. The plastic enters through the hopper filling the barrel . The heating elements bring the barrel to temperature and melt the plastic inside. the plastic is molten and ready to be injected. This was done to test the recycle material behaviours and results.

After getting the plastic flakes from the shredder, the flakes are kept in seperate box according to their properties.

Once the Recycling process done, we moved to designing and prototyping, for the designing we tried different pattern and algorithm. One of design pattern was curve growth 3d printing.

Depend on design, we print few prototypes on flat surface and made a mold for specific product . Despite having all the qualities of lightness, flexibility & strength, and the shortest & strongest pass. when translated to printed outcome the resulting curve will lead to areas of excess material while leaving holes in the others more widely placed. This is because of the width of extrusion always being constant from the mounted 3d printing tool. to ensure the printing width always intersects at half the printed width a curve growth is applied to ensure the best-printed pass while keeping all the data from the steps so far in the process. The file after running through these processes is ready to be printed on the robotic arm.

RECYCLING

DESIGNING AND PROTOTYPING

HYBRID TOOL

Image Source: Pinterest

For a closed robotic system using both methods we need both tools mounted on the robot or at least available for an automatic tool change. Milling-Spindles are already in use in a robotic system just adapted form CNC-milling machines and attached to the robot. In case of 3d-printing in a big scale normal filament extruder are just too small to print in thick layers and fast. So the only possibility is to use pellet extruders. But the market of pellet extruders for big scale 3d-printing is still in a stage of research and DIY-solution. There are just a handful of solutions for big scale 3d-printing but they are used as standalone products .

Image Source: Dirk Vander Kooij

HYBRID TOOLS

A comparison between all these DIY pellet extruders brought us to the conclusion, that the longer the auger screw and the surrounding pipe is, the more material can be extruded in a shorter time.

HYBRID TOOLS

Image Source: Dirk Vander Kooij

Some people like the dutch designer Dirk van der Koij developed their own pellet extruders step by step to get to a certain material extrusion. The classic pellet extruder works with an auger screw which transports the pellets into a pipe more and more down to a section where bandheaters are heating up the pipe and as well the material to its considered printing temperature. The auger screw transports the material out of a nozzle with the defined printing diameter. The principle is adapted from industrial injection molding machines.

But we also need a senseful combination of both tools, the pellet extruder and a milling spindle. One approach could be the combination of both tools in one endeffector. In this scenario the tools shouldnâ&#x20AC;&#x2122;t intersect the other one while doing his job.

Another approach is coming from the german based company Datentechnik Reitz, which developed together with a german university a hybrid tool where one tool is 180 degrees rotated on the back of the other tool. The robotic axial freedom allows both tools to act completely free. But this setup is still in a development stage and just useful for small pieces .

Image Source: KRAKEN Concept, EU

The kraken project, claims to put both tools in a row and have the pellet extruder on a seperate moveable axis in the front of the milling spindle. By changing the process from milling to to 3d-printing the extruder is moving done and is much closer to the object then the spindle and also the spindle could be removed to a automatic toolchanger.

Image Source: Datentechnik Reitz

CONCLUSION The combination of both manufacturing processes in one tool or as changeable tool in an automated tool changing process is necessary for the economical mass customization. The setup should also integrate a suction system for milling waste to feed back into the printing process. In the end these tool requires a lot of different points of view and technological knowledge. So it will take much longer to find a working hybrid tool on the market then a working AM-tool.

CONCEPT

Image Source: Pinterest

REAL 3DPRINTING

CNC MILLING

FINAL PROTOTYPE

The design of the structure of the chair based on loading scenarios and the thermoplastics we planned to use dictated by Autodesk Fusion 360 Generative Design suite. Over a 100 suitable designs were churned out by the algorithms reckoning traditional print parameters and printing logic based on Z-discretization and 2.5D-Printing. However, when seen from a hybrid-manufacturing standpoint, the printing strategy becomes easier and the print more plausible. We can take advantages of Hybrid Manufacturing by printing faster using a higher resolution while relying on milling for the final surface finish. Finer details or tolerances can be attained through the subsequent milling. Moreover, designs which require a lot of support material can be printed as these can be milled out in the post-processing stage, thus widening the design possibilities for additive-manufacturing by allowing overhangs.

GENERATIVE DESIGN

ALGORITHMIC DESIGN

The Iterative logic preceding design logic is constituted on overlapping circular fields pushing away from each other, leaving behind a trail of polyline perfectly equidistant to each other invariably. On an optical outlook the script resembles a curve growing but these curves are perfectly equidistant from each other, perfect for 3D printing ensuring a perfect printed overlap despite the location in the printed pass. To simply explain the process consider 2 circles overlapping and to push away from each other in the resulting opposite vector. The complexity arises when when the resulting vectors to repel arise from 3 or more overlapping circles, to compute the average move vector for each circle and move each circle according to the average move vector. This iteration repeats indefinitely reducing the overlapping until there is absolutely no overlap. This constitution of no overlap is calculated simultaneously with the finished iterations and with newly added iterations to ensure the script can be used in indefinite growth while ensuring the equidistant spacing in between, eg. 3 circle overlap will recompute if new iterations of i and j are added.

The algorithm that we have chosen to exercise is using differential growth. What we wanted to do was create a system that behaved similarly to surfaces in nature that fold in on themselves. For instance the way walnuts do, as well as the layers of cabbage, our intestines and several leaves and flower petals. And probably several other things.

ALGORITHMIC DESIGN

The surface for exercising the design was chosen to be that of the chair when translated to printed outcome the resulting curve will lead to areas of excess material while leaving holes in the others more widely placed. This is because of the width of extrusion always being constant from the mounted 3d printing tool to ensure the printing width always intersects at half the printed width a curve growth is applied to ensure the bestprinted pass while keeping all the data from the steps in the printing process Translating the curve growth on a double curved surface terraforms its presence while perfectly packing the surface. The boundary of the surface defines the end of the growth, in theory the lack of uniformity in direction of the print pass prevents its own infallibility to forces in any one direction. Yet a boundary of 3 passes on the surface boundary concretes its stability by uniformly distributing its forces through the periphery.

TOPOLOGY OPTIMIZATION

HYBRID DESIGN The Hybrid Design presents a method for generation of 3D models based on shape and topology optimization, while giving the freedom to customise each layer of the optimized geometry. The optimization procedure, or model generation process, is initialized by a set of boundary conditions, an objective function, constraints and an initial structure. Using this input, the method will automatically deform and change the topology of the initial structure such that the objective function is optimized subject to the specified constraints and boundary conditions. In our dissertation we ran 17 iterations of topology optimization and redesigned the optimized structure to a more finished output, while keeping the principles of topology optimization, This method can be used to improve the stiffness of a structure before printing, reduce the amount of material needed to construct a bridge, or to design functional chairs, tables, etc. which at the same time are visually pleasing. The presented method is the first to optimize both the 3D shape and topology of a surface mesh with the use of an implicit customisable printing pass. The first layer utilises Differential Growth Algorithm to create a single polyline, the next layer uses a continuous Spiral and finally the Linear printing pass. Consequently, the method accepts a surface mesh as input and outputs a 3D printed geometry which has been optimized and fine tuned in stiffness, elasticity, tension and compression relevant to the desired product. Furthermore, as opposed to standard fixed grid methods, our method makes it possible to generate detailed designs within reasonable time by anybody willing to test the relationship between design and finished product.

90 m 84 m 59

HYBRID DESIGN

FABRICATION PROCESS

MOLD FABRICATION

MOLD FABRICATION: Milling

A double-curved surface was discretized into 32 elements that could be milled out of a straight MDF(Medium-Density Fibreboard) board of the dimensions (*2.5x0.6*0.03* meters). The geometry allowed using a 3-axis CNC machine for the operations involved. The milling strategy involved: 1. 2. 3.

Roughing Profiling Finishing

The total milling time was about 6 hours. These parts were assemble d together in the next stage to take the shape of the mold

MOLD FABRICATION: Assembly

The discretized elements once milled were assembled with reference to the design. Consecutive elements were stuck with PVA glue. The top surface was sanded and finished for a smoother finish. Later, coatings of various thermosetting polymers was applied to ensure that the 3d-print sticks well to the surface

3D-PRINTING ON A MOLD : SURFACE COAT FOR DIFFERENT KIND OF MATERIALS TO STICK ON BUT ALSO EASY REMOVING 1. Putty on Mould We applied following putty to surface for the surface hardness, durability and smooth finish. Name : Masilla Tapagrietas Color : White Process : Thin layer of paste applied on mold, it is lightweight material so easy to apply. its Dry quickly and helpful to fill the holes and marks on the mold and then achieved the smooth surface after sanding Result : Its Smoothen the mold Surface but not suitable for printing, the hot Printed layer sticks to mold and make a mark on the surface. Other Applications of the Putty : Indoor use on a lot of construction materials, cement, concrete, plaster, plasterboard, brick, wood, etc. even on old paint in good condition

2. SPRAY PAINT The printing on mold did not worked properly so we shifted to another test which was spraying paint on the mold. Color : Black Process : 1. 2. 3.

We took a piece of MDF Board to apply the Spray Paint Wiped the Piece from cloths to clean of any dust. Applied first coat of spray paint and kept it for drying 5 minutes, then again applied 2nd and 3rd coat to get solid color and thick layer.

3D-PRINTING ON A MOLD

3D-PRINTING ON A MOLD : SURFACE COAT FOR DIFFERENT KIND OF MATERIALS TO STICK ON BUT ALSO EASY REMOVING

Result : Its Smoothen the mold Surface but not suitable for printing, the hot Printed layer sticks to mold and make a mark on the surface.

3D-PRINTING ON A MOLD : SURFACE COAT FOR DIFFERENT KIND OF MATERIALS TO STICK ON BUT ALSO EASY REMOVING 3. HIGH TEMPERATURE EPOXY GELCOAT Make : FORMX (Polyster Gelcoat) It is an advanced epoxy gelcoat designed primarily for use in the production of high temperature moulds/tools for prepreg and resin infusion. EG160 uses a unique unfilled formulation which results in superior surface finish and polishability whilst still achieving excellent stability at service temperatures up to 160°C. Color : Transparent and Black pigment Added Process : Sand the MDF Board Mold which is already sealed with putty to create a mechanical bond with the gelcoat. Next cleaned the surface and Applied gelcoat first coat on mold relatively thin. Result : Its Smoothen the mold Surface but not suitable for printing, the hot Printed layer sticks to mold and make a mark on the surface. Key Features : • High temperature use up to 160°C • Suitable for prepreg tooling • Highly polishable • Superior surface finish • Simple brush application Other Applications : • Gelcoat on moulds for prepreg manufacture • Gelcoat on moulds for high temperature epoxy infusion • Gelcoat on high service temperature epoxy components

POLYURETHANE TYPE 1 :

Make : EBALTA (MG 321 FR / Comp. A+B) The EBALTA MG 321 FR is a ultra-low viscosity casting resin that yield castings that are bright white/ivory and virtually bubble free. Vacuum degassing is not necessary. It offers the convenience of a 2A:1B, 3A:1B, 4A:1B by volume in different Working and cured times as per the specific purpose.It can be colored by adding pigment or after getting dried. Fully cured castings are tough, durable, machinable and paintable. They resist moisture and mild solvents.

3D-PRINTING ON A MOLD

3D-PRINTING ON A MOULD : SURFACE COAT FOR DIFFERENT KIND OF MATERIALS TO STICK ON BUT ALSO EASY REMOVING

Ebalta MG 321 FR is processed on a two-component low pressure device. After grinding with a sand paper , grit 280, the surface can be varnished with a commercial lacquer. For better adhesion we use putty coat. Color : White / Ivory Process : It is essential to stir component A before use, as the additives tend to sedimentation. Component B has not to be stirred. Weigh or measure both parts accurately and assemble in a clean and dry container and mix for 30 to 60 seconds. For the mixing cup, used PP plastic cups. Avoid contact with moisture as this will cause foam formation of the resin. After mixing apply it in 1 - 3min as per the volume proposition before it get dried. Result : It has working and curing time very less, is an easily pourable, thin-flow polyurethane cast resin that is suitable for mold to achieve the even and finished surface for material to stick on it but also easy removing. . its high heat resistance so does not create problem while extruding material on to surface. Multiple Test with Different Proportions 4a. Test 1 with Proportion 3 : 1 4b. Test 2 with Proportion 2 : 1 4c. Test 3 with Proportion 4 : 1 Pros : ● ● ● ● ● Cons. : ● ●

Low viscosity - captures excellent detail - no degassing necessary high heat resistance Resin cures to a bright white/Ivory finish It can be sanded, drilled, sawed and - after degreasing - painted Cured castings are strong and durable and resistant to moisture and mild solvents. Working time and cured time is very less where the mix ratio is equal or lower, difficult to apply on surface after 1-3 min. Depending on the ratios In higher ratio, it take time to dry.

Other Application : Ebalta MG 321 FR is suitable for industrial use such as making Cladding parts EDP field , Cladding parts medical sector, Interior / Exterior of rail vehicle and prototyping of all the scale and complex shapes.

3D-PRINTING ON A MOULD : SURFACE COAT FOR DIFFERENT KIND OF MATERIALS TO STICK ON BUT ALSO EASY REMOVING 5.

POLYURETHANE TYPE 2 :

Make : FORMX (FormCast Rhino) The Form Cast RHINO liquid plastic is an ultra low viscosity resin with ivory color. When properly used it will yield strong, detailed and bubble free castings. Vacuum degassing is not necessary. This resin may be mixed with various fillers and dyes. Cured castings are strong and durable and resistant to moisture and mild solvents. They can be sanded, drilled, sawed and - after degreasing painted. Color : Ivory plus black pigment added Process : Stir the individual components well before use. Weigh or measure both parts accurately and assemble in a clean and dry container and mix for 30 to 60 seconds. For the mixing cup, used PP plastic cups. Avoid contact with moisture as this will cause foam formation of the resin. After mixing apply it in 9 - 15 min before it get drying. Result : FormCast Rhino is an easily pourable, thin-flow polyurethane cast resin that is suitable for mold to achieve the even and finished surface for material to stick on it but also easy removing. . its high heat resistance so does not create problem while extruding material on to surface. Benefits : ● ●

● ●

Cured castings are strong and durable and resistant to moisture and mild solvents. It can be sanded, drilled, sawed and - after degreasing - painted, its Compressive Strength is 47 ± 5 Mpa as per EN ISO 604 Standard and E-modulus 1000 ± 100 Mpa as per EN ISO 178. Short demoulding time and heat resistance, Heat Stability (HDT) 84 ± 3 ˚C . low viscosity

Other Application : Form Cast Rhino is suitable for industrial use such as making foundry patterns, core boxes, vacuum forming tools, mold surface top layer finish and prototyping of all the scale and complex shapes. Typical uses include the manufacturing of prototypes, models, sculptures, decorative articles, anatomical models etc.

LAYER 1: ALGORITHMIC DESIGN

LAYER 2: SPIRAL DESIGN

LAYER 3: LEGS

MILLING

MILLING To achieve the third layer, governed by topology optimization, a router with a ball mill was used. The idea was to showcase the advantages of the hybrid workflow. Thus two critical operations related to a product are the surface finish as well as the tolerances involved with it to be assembled with other parts. Hence, we milled the chair deep enough until the first layer to portray the grooves dictated by topology optimization. Secondly, the holes which house the legs of the chair were milled to ensure that the the wooden leg has a tight interference fit with the chair itself. These operations when scaled to the entire chair would take about 90-120 minutes to mill.

CONCLUSION

ADDONS

Image Source: Pinterest

Additional functionalities which could aid Hybrid-Manufacturing have been explored in this section. Technologies like sensing during the printing procedure, advanced algorithms for an amorphous structure-based design strategy, photogrammetry and tactile scanning the mold or adaptive molds have been researched and explored. These â&#x20AC;&#x153;smart add-onsâ&#x20AC;? when integrated with Hybrid-Manufacturing could enhance the accuracy, structure and curb other problems atypical to integration of two different manufacturing strategies

SENSING

SENSING: Printing with sustainable materials proves to be challenging due to the myriad number of print parameters that are needed to be calibrated for each new batch of material. Hence we saw an opportunity to automate this task, which conventionally requires meticulous visual feedback and manual fine-tuning. An OpenCV script was used to detect the print, determine the width of the print and correspondingly calculate the error in RPM of the extruder motor based on the distance of the camera to the print as seen in Fig.1. The robot-speed and extrusion temperature is kept constant during the test while extruder speed is calibrated. Following this, we can progress with the actual print. This proof of concept can be extrapolated to sensing and feedback during the course of an entire print using thermal and/or depth cameras to ascertain flow-rate uncertainties common with pellet extruders, or older batch of materials that is affected by humidity. Fig 1. OpenCV script controlling the extruder motor speed for calibrating the print parameters AI-Build, a London-based company, recently revealed a similar vision-based feedback system integrated with their robot-printer setups. They were successful in creating a data-set for various print failures and the ways of troubleshooting them and integrate these learn parameters in the model to correct a print in real-time based on the learnt parameters. This system represents our vision based on the number of printing faults like warping, stringing, delamination, over/under-extrusion. The machine-learning algorithms can make it easier to incorporate print parameters like extrusion temperature, robot speed, print motor speed. These can be tailored to solve a particular problem using a combination of these parameters, while minimizing the printtime.

Fig 2. AI Buildâ&#x20AC;&#x2122;s system based on computer-vision and an ML dataset for real-time feedback

AUTOMATED PATH PLANNING BY AI While tackling solution in terms of manufacturing standards, problems specifically arising from the hybrid manufacturing technique present themselves. Design solutions to this new technique could factor in new elements such as lightness, strength, production speed and efficient print. The role of Machine Learning: Fuzzy Logic takes place in determining the optimum length of printing filament while adhering to the topologically optimized data ensuring the quickest print pass. Printing with an AI guided design is relatively constituted and debatable in many senses, but we we believe it can optimise the the efficiency of implied aesthetic subtly. For the purposes of validating our method as a solution that can compete with standard processes in terms of time, quality and overall efficiency. The input for the geometry is the surface of the chair we will be printing on. Based on the forces acting on the surface, data on where topology optimization would be required can be derived. The translation of the topology optimization data into usable means is done by a circle packing logic reading the gradient values from topology optimization. Introducing this logic reduces the number of printed layers while keeping the stiffer layers in the required areas and flexible layers in the others in a transitional manner. Point clustering is another step for translating the topology data into points which would be useful in the steps following. To connect the points and generate the most optimal moving pass a machine learning algorithm involving fuzzy logic senses the distance to the points surrounding it and moves crisscrossing between points of different proximities while avoiding immediate recursions i.e. in movement 1 it will move to x distance whilst in movement 2 it will move distance z or y or 2x. Furthermore, it avoids self-collision while running its iteration as this translated to actual printing will not be a feasible result. The path correction and collision detection from the fuzzy logic invariably creates a crisscross running from dense to less dense and vice versa in a cluster of structurally oriented points to further the relation of flexibility with strength; nonetheless, ensuring the most efficient path length whilst doing so.

3D printer trajectory planning can be used to improve the speed of the printing process. The printing speed mainly depends on the motion speed and path of the printing nozzle. Users can use triangular, trapezoidal or any other velocity profiles to minimize the transition time between print segments. In this work, several algorithms can be proposed as solutions for conventional methods and can be modified to adapt to the new problem and experimentations. The proposed modifications can be designed to obtain time-efficient trajectories for the printing nozzle.

CUSTOMISED PATH PLANNING

Certain considerations can be made so solve the path planning problem. A problem of connecting existing edges, instead of nodes. It does not require a path to return to the start node (origin). Its objective is to minimize the total traversal time, instead of path length. It can be further specified in terms time durations using the motion control model by modifying several algorithms for the 3D printer path planning problem. 3D printing speed can be improved by optimizing the motion path of the nozzle and selecting effective velocity profiles for each segment of the path. A motion path usually consists of print segments and transition path segments. This work utilizes a motion control model which can ensure uniform material deposition on print segments and short transition time on the rest of the path. Algorithms can be modified to find fast trajectories for the nozzle. Further experiments which cannot be done using traditional 3D printers can be carried out to verify the applicability of the various proposed trajectory planning techniques. Users can consider trajectory planning over traditional single layer of a 3D object. Therefore, research can focus on optimizing trajectory of the nozzle across multiple layers, while assigning various new properties of weight reduction, increased strength, variable flexibility, topology optimization and various others .

SCANNING: PHOTOGRAMMETRY

The role of photogrammetry in mapping physical objects into a codable environment (image acquisition and image measurement). Mathematical relations between acquired images and object space to record the information. The direct and inverse problems of projective and similar coordinate transformations is solved by the photogrammetry software. Cordiantions of collinearity and coplanarity are also assimilated to be utilized. The first stage is camera alignment, where common points on photographs and matches them, as well as finds the position of the camera for each picture and refines camera calibration parameters. As a result a sparse point cloud and a set of camera positions are formed. The next stage is generating dense point cloud, that is built by PhotoScan based on the estimated camera positions and pictures themselves. Dense point cloud may be edited and classified prior to export or proceeding to the next stage. The process is further used to analyse the point deviation from the original Stereo-model by means of error analysis.

A carpenter or artisan uses his/her hands to feel the materiality and unevenness of the surface. This human touch is essential for actions like sanding, polishing etc. However, such low-level feedback is missing from the robotic processes. We hypothesized that we could use the torque sensors on the Kuka iiwa robot to have this tactile feedback.

TACTILE SCANNING

In the project we also tried to align the robot, while scanning the shape, according to the shape-normals by receiving the forces and the direction of the forces . But there where a couple of theoretical problems like the buffer between receiving the forces and realigning while moving on the surface and also detected forces which where not useful for a normal realignment. But in case of tactile scanning we received promising results, which we gave much trust because we received always the actual position of the Robot-TCP calculated over the 7 joint-positions of the robot. And they are quite accurate as we imagine. In comparison to photogrammetry, looking on one certain line of the surface, photogrammetry seem to has much more inaccuracies and noises in the measurement. Finally to evaluate the accuracy of tactile scanning with a Kuka iiwa we need much more points and measurable physical points to compare the digital results with the physical structure.

APPLICATION S

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Large-scale robotic systems with more than three degrees of freedom have been explored for fabrication (in particular, 3dprinting and milling for metals, foam and thermoplastics) by disparate research group and companies around the world. Sustainable materials and the concept of cradle-to-cradle materials have been explored outside the context of additivemanufacturing. The following case-studies explore these differentiated technologies in the context of a robotic hybridmanufacturing system.

Instead of relying on the traditional, complicated assembly line of machines and people sculpting and piecing together parts of a vehicle, Relativity wants to make building a rocket almost entirely automated. The trick? Using giant 3D printers that can create all of the parts needed to build a rocket — from the engines to the propellant tanks and structure. Process : Relativity has the largest metal 3D printer by volume, a machine that’s capable of creating parts that are up to 20 feet tall and 10 feet wide. It’s called Stargate, another nod to Starcraft, and the team designed this printer from scratch, which means they can scale it up if needed. By relying on printers like this for manufacturing, teams will be able to produce about 95 percent of the rocket through 3D-printed automation. The last 5 percent still requires human labor. Most of that human interaction will be centered on testing, shipping, and very small amounts of manual assembly.

AEROSPACE INDUSTRY

AEROSPACE INDUSTRY : 3D PRINT AN ENTIRE ROCKET IN 60 DAYS

Post processing of the 3D print consists of 2 robots analysing the printed geometry, thereby automating the whole process of production.

Relativity’s Aeon engine undergoing a test fire at Stennis Space Center. Photo: Relativity Space Relativity’s Stargate 3D printer at the company’s LA headquarters. Photo: Relativity Space Source : https://www.theverge.com/2019/1/17/18185136/relativity-space-3d-printing-terran-1-rocket-cape-canaveral-florida

AEROSPACE INDUSTRY : 3-D printing could reduce airplane's weight by 4 to 7 percent Stratasys Direct Manufacturing, a subsidiary of Stratasys Ltd. (Nasdaq: SSYS) and one of the worldâ&#x20AC;&#x2122;s largest 3D printing and advanced manufacturing service providers, has been chosen by Airbus to produce 3D printed polymer parts for use on A350 XWB aircraft. The company will print non-structural parts such as brackets, and other parts used for system installation, on Stratasys FDM production 3D Printers using ULTEMâ&#x201E;˘ 9085 material. The project will help Airbus achieve greater supply chain flexibility and improve cost competitiveness, while leveraging on reduced material consumption and waste. Process : Stratasys used an ULTEM 9085 resin, which is certified to an Airbus material specification, to fabricate each part on an FDM 3D printer, melting the resin and extruding it layer by layer until entire parts are fabricated. This production method not only produces parts which are lighter in weight and incredibly strong, but they also are FST (flame, smoke, and toxicity) compliant. Stratasys solutions offer design freedom and manufacturing flexibility, reducing time-to-market and lowering development costs, while improving products and communication. Subsidiaries include MakerBot and Solidscape, as well as Stratasys Direct Manufacturing, which offers 3D printed parts on demand. Conventional manufacturing methods tend to be inefficient and wasteful. To produce a 1-kilogram bracket for an airplane, for example, it may require 10 kilograms of raw material input into the manufacturing process. And, from an engineering design perspective, that final bracket may still contain much more metal than is required for the job. 3D-printing, on the other hand, requires far less raw material inputs and can further produce parts that minimize weight through better design.

A350 XWB aircraft interior. Photo: Stratasys

Brackets 3D printed on the Fortus 900mc Production 3D Printer. Image via Stratasys. Source : https://3dprint.com/63169/airbus-a350-xwb-3d-print/

SABIC believes that these new generation (3D printable) materials can play a major role in not just making aircraft more affordable, but also in improving the aesthetics.Aircraft interiors are bound by complex manufacturing regulations, but SABIC is currently highlighting several materials in Hamburg that could be perfect for the next-generation of aircraft components. Among them are the extremely light-transmitting CLEAR LEXAN XHR2000 sheets(when uncoated), the CLEAR LEXAN XHR2HC1 and LEXAN XHR2HC2 sheets, and a number of other new materials. Process : A seatback made from SABIC’s LEXAN LIGHT F6L306 sheet. With a specific gravity of 0.85 g/cm3, this product is the lightest thermoplastic sheet option available today, up to 40% lighter than PVC/PMMA sheet products. The material complies with typical industry FST and Boeing/Airbus toxicity requirements and is thermoformable into complex 3D-shaped parts with very thin walls, down to 0.6mm. The seat was printed by Stratasys, using SABIC’s ULTEM 9085 resin. ULTEM 9085 resin is highly compatible with 3D printing and is FAR 25.853 and OEM toxicity compliant and offers low moisture absorption and design flexibility. Use of 3D printing enabled the rapid prototyping of the Studio Gavari design, resulting in a seat with less than 15 components. A range of wicking, cushioning and acoustical materials, made with ULTEM fibers, selected for its low moisture absorption, high heat tolerances and compliance with industry and OEM standards, sound absorption, lightweight and recyclability.

SABIC’s color service offers aircraft interior designers consultative color and aesthetic services, including custom color creation, color matching and color management for a customer’s global supply chain.

AEROSPACE INDUSTRY

AEROSPACE INDUSTRY : 3D printed economy class seat / Mass customisation

Brackets 3D printed on the Fortus 900mc Production 3D Printer. Image via Stratasys. Source : https://www.sabic.com/en/news/7343-sabic-wins-two-european-plastics-innovation-awards

ARCHITECTURE : 3D PRINTED URBAN STRUCTURES Robotic 3D Printed Modified Plastic Footbridges on Display at Tongji University: When we talk about 3D printed bridges, they’re usually made out of heavy construction materials, like concrete or steel. But recently, Tongji University’s College of Architecture and Urban Planning (CAUP) unveiled the first robotic 3D printed bridges, which were made using modified plastic. The two black footbridges, which span 4 meters and 11 meters. This event definitely seems to breed 3D printing innovation: a team attending the workshop in 2015 developed a 6-axis robotic 3D printer that was inspired by spiderwebs, and the Silky Concrete project from Beijing’s Silk Project spatial lab was also a result of the workshop. Based on the principle of traditional three-dimensional printing, the possibility and feasibility of three-dimensional printing of building scale are explored in combination with structural performance design. Using the robot three-dimensional printing to realize the batch production of custom unit, we complete two pieces by customizing the threedimensional printing module masonry. Three-dimensional printing bridge, span of 4 meters and 11 meters, respectively, to verify the three-dimensional building products, structural stability and reliability. The robot platform provides a new possibility for the development and implementation of 3D printing technology, which makes the feasibility of applying 3D printing technology to the construction industry, both on a scale and a complex system. The same can be implemented more feasible by hybrid Manufacturing.

Image : Robotic 3D Printed Modified Plastic Footbridges on Display at Tongji University https://3dprint.com/181596/3d-printed-footbridges-tongji/

ARCHITECTURE

ARCHITECTURE : 3D PRINTED HOUSES AND PANELS World's largest 3D-printed polymer building designed for off-grid living : Architecture firm SOM has created a 3D-printed structure,, providing a model for off-grid living. The SOM-designed pavilion is composed of 3D-printed panels that serve multiple purposes. In addition to acting as exterior cladding, the panels provide structural support, insulation and moisture protection. This all-in-one approach cuts down on construction waste and reduces material usage, according to the design team. "SOM and its partners optimised the structure's form to reduce the amount of material used and to express three-dimensional printing's ability to deploy complex, organic geometries," said the firm. The structure measures 38 feet long (11.6 metres) by 12 feet high (3.7 metres) by 12 feet wide (3.7 metres). The building envelope comprises approximately 80 per cent opaque panels and 20 per cent glazing, resulting in a highly efficient enclosure. 3D printing is increasingly scaling up from objects to houses and infrastructure. With the help of robot, s a new possibility for the development and implementation of 3D printing technology, which makes the feasibility of applying 3D printing technology to the construction industry, both on a scale and a complex system. The same can be implemented more feasible by hybrid Manufacturing.

Image : 3D-printed panels

Image : 3D-Printed polymer building Structure

https://www.dezeen.com/2016/01/25/additive-manufacturing-integrated-energy-3d-printed-structure-som/

ARCHITECTURE : 3D PRINTED HOUSES AND PANELS Dutch EU building features a facade combining tensile fabric and 3D-printed bioplastic : DUS Architects has combined 3D-printed bioplastic with a tensile fabric structure to create a sculptural facade for the building and the facade can be recycled. Tensile fabric structures are commonly used for temporary structures, so the team decided to combine this with their recent research in bio-based 3D-printing filament. They have developed a special plastic that is entirely bio based, made out of linseed oil, The advantage of this material is not only that it is made out of plants, but that it can be shredded and reused in the print cycle. The fabric structure provides the main shape of the facade â&#x20AC;&#x201C; a series of vertical panels that appear to have been lifted up at the base to create triangular openings reminiscent of tent entrances. The intention was for these forms to reference the sailing ships that were historically built in this area. Within these openings, faceted blue surfaces extends out to create benches. These elements were all created using 3D printers. This is the first time in the world that these kinds of "XXL 3D prints" are being shown in the public domain, according to DUS Architects. They were created using fused deposition modelling, the same form of additive manufacturing used by most household 3D printers. The FDM technique is the most common way of producing small objects, but here they have scaled up this technique for much larger elements

Image : Dutch EU Building features a facade combining tensile fabric and 3d printed plastic.

89 https://www.dezeen.com/2016/01/12/european-union-3d-printed-facade-dus-architects-holland/

Composite skeleton, Tallinn, 2015 : Composite Skeleton is a composite fibre prototype developed for the Talliin Architecture Biennale and exhibited in Estonia. The translucent skin of the prototype is 0.25mm thick and provides the shear strength of the project, while the black skeleton is 2mm thick.

ARCHITECTURE

ARCHITECTURE : MOLDS

This project was supported by: RMIT University School of Architecture and Design and the Tallinn Architecture Biennale. The prototype was designed by Kokkugia and fabricated by students within the RMIT studio 'Composite Pavilion' taught by Roland Snooks and Cam Newnham Meeting pavilion, Melbourne, 2015 : This Meeting Pavilion was space for discussion and debate. Not a neutral space, but one that is rich in crafted detail. The exterior shell will be fabricated from fibre-composite materials creating a depth and subtle translucency, with the interior lined in quilted fabric. The robot platform provides a new possibility for the development and implementation of 3D printing technology and mold makings for sculpture and installation, which makes the feasibility of applying 3D printing technology to the product design, both on a scale and a complex system. The same can be implemented into more feasible by hybrid Manufacturing.

Image : Composite skeleton, Tallinn, 2015

Image : Meeting pavilion, Melbourne, 2015

90 http://www.rolandsnooks.com/#/composite-skeleton/ http://www.rolandsnooks.com/#/meeting-pavilion/

ARCHITECTURE : 3D PRINTED MODELS 3D Printing in Architecture Models : Today architects use 3D printing mainly as a tool for conceptual models and show models to motivate prospective clients and investors. It is an excellent complementary tool for rendering images and computer models. Communicating the idea – giving a depth, dimension, and texture to a project – it’s an excellent way to stand out from the other firms. Today architects use 3D printing mainly as a tool for conceptual models and show models. It is an excellent complementary tool for rendering images and computer models. Communicating the idea – giving a depth, dimension, and texture to a project – it’s an excellent way to stand out from the other firms. The Technology improves the efficiency of the workflow. Following are the key 3d Printing Benefits: ● ● ● ● ● ● ● ● ●

Faster and cheaper Easy iteration.test multiple design concepts Immediate understanding Completely digital workflow Design freedom. complex shapes and forms Easy fabrication of multiple copies Visualization for stronger impression Reduce, reuse, recycle Increase productivity

Early stage models : With 3D printing, discussions using concept models from day one is convenient way to design. Urban planning : Within very less time we can 3D print an entire city, incorporating all visionary thoughts and concepts for every inch of it. Model variations : With 3D printing you can quickly print as many model variations as you like, it allows to get to the final design quickly and affordably. The robot platform provides a new possibility for the development and implementation of 3D printing technology, which makes the feasibility of applying 3D printing technology to the quick model making, both on a scale and a complex system. The same can be implemented more feasible by hybrid Manufacturing.

91 Image : Bigrep 3D Printing in Architecture contour and models.

Exploratory design stage in the automobile industry involves using of a huge block of foam and overlaying it with clay for milling, followed by manual post-processing. This giant block of foam is expensive to produce and ship and relying on subtractive manufacturing leads to huge amounts of waste. Recyclable thermoplastics open the door to reuse the milled material for printing again. Moreover, can this conventional workflow be improved by hybrid manufacturing which offers lower wastage and costs?! With the advent of an integrated hybrid-manufacturing system, a master-mold can be used to print the outline of the body, without using up material in the bulk of the prototype. This base shape can be invariant of the final design and can be used indefinitely. The overlaying print parameters change with each subsequent design iteration. However, this flexibility can only be attained by still relying on the milling to produce finer details. Production time is more due to the added printing time but the milling time is reduced as horizontal roughing isnâ&#x20AC;&#x2122;t needed in the case of hybrid-manufacturing. The development of a system for this requires a deep integration of the additive-manufacturing extruder as well as the milling spindle. Any deviations between the digital model and/or calibration between the two end effectors can lead to inaccuracies. A fully dedicated system thus could be the answer to the often tedious procedure that involves specialized personnel rather than just people with skills in machining. Moreover, recyclable materials could be integrated into the workflow.

AUTOMOTIVE PROTOTYPING

AUTOMOTIVE PROTOTYPING: FOAM+CLAY MODELS

PRINTING ON DIFFERENT MATERIALS

FUTURE

REPAIRING PRODUCTS

AUTOMATE PATH-PLANNING BY AI

Printing on different materials casts the way to repairing broken products

PRINTING ON DIFFERENT MATERIALS

REPAIRING PRODUCTS

AUTOMATE PATH-PLANNING BY AI

SMARTER ALGORITHMS FOR PATH-PLANNING

REGIONAL PRODUCTION. REPAIRING PRODUCTS

In the future, smarter algorithms dictating the most optimized strategies in terms of material usage, time and costs will enable a smarter production procedure. From the industry perspective, hybrid manufacturing will enable 0-km production without draining the resources of the region, while ensuring economic and environmental sustainability. The current material life-cycle will go from cradle-to-grave to cradle-to-cradle.

BIBLIOGRAPHY PAPERS Suitability of recycled HDPE for 3D printing filament Haruna Hamod Thesis : Plastic Technology 12/2014

Hybrid Processes in Additive Manufacturing Michael P. Sealy, Gurucharan Madireddy, Robert E. Williams, Prahalada Rao, Maziar Toursangsaraki 2018

Additive Manufacturing for Aerospace Schiller, G.J. United Launch Alliance 2014

A Robot FDM Platform for Multi-Plane and 3D Lattice Structure Printing Ismayuzri Bin Ishak 07/2018

Additive manufacturing trends in Aerospace Joe Hiemenz, Stratasys, Inc. 2014 3D printing in aerospace and its long-term sustainability Sunil C. Joshi & Abdullah A. Sheikh 2015 Large scale 3D printing: feasibility of novel extrusion based process and requisite materials Muhammad Harris, Johan Potgieter, Khalid Arif, Richard Archer 2017 A novel building strategy to reduce warpage in droplet-based additive manufacturing of semi-crystalline polymers Andreas Schröffer, Jelena Prša, Franz Irlinger and Tim C. Lüth. 2018 An Additive and Subtractive Process for Manufacturing with Natural Composites Stylianos Dritsas, Yadunund Vijay, Marina Dimopoulou, Naresh Sanadiya, Javier G. Fernandez 2019 A review of hybrid manufacturing K. A. Lorenz*†, J.B. Jones§, D. I Wimpenny* and M.R. Jackson† 2015

Direct pellet extruder developed for LEDC - Masterthesis Paolo von Krogh 2017

BIBLIOGRAPHY WEBSITES https://akro-plastic.com/process-and-technology/additive-manufacturing/ https://www.additivemanufacturing.media/blog/post/10-ways-3d-printing-isadvancing-plastics-manufacturing(2) http://www.hybridmanutech.com/ https://eurecat.org/en/field-of-knowledge/plastic-materials/ http://www.stratasysdirect.com/technologies/cnc-machining/benefits-cncmachining-fdm-parts https://www.wired.co.uk/article/adidas-futurecraft-loop-running-shoe-recycle https://omnexus.specialchem.com/polymer-properties/properties/stiffness https://arstechnica.com/information-technology/2018/12/unite-day2-1/ https://phys.org/news/2015-06-case-d-airplane-weight-percent.html https://www.autodesk.com/redshift/bionic-design/ https://3dprint.com/63169/airbus-a350-xwb-3d-print/ https://medium.com/@worldofchemical/sabic-introduces-new-design-services-foraircraft-interiors-5ca4125323ea https://www.stratasysdirect.com/industries/aerospace/3d-printing-transformingaircraft-interiors https://bigrep.com/posts/fully-3d-printed-high-tech-airline-seats-premiered-aircraftinteriors-expo-hamburg/ https://www.slideshare.net/garacaloglu/how-it-is-made-plastic-chair https://rucothel.com/ https://www.youtube.com/watch?v=WvZYppXNsoo https://www.youtube.com/watch?v=KTTWiCUBeXg

Robotic Hybrid Manufacturing

Articles inside

AUTOMOTIVE PROTOTYPING: FOAM+CLAY MODELS

3D PRINTED MODELS

MOLDS

3D PRINTED HOUSES AND PANELS

3D PRINTED URBAN STRUCTURES

3D printing could reduce airplane's weight by 4 to 7 percent

3D PRINT AN ENTIRE ROCKET IN 60 DAYS

3D printed economy class seat / Mass customisation

SCANNING: PHOTOGRAMMETRY

TACTILE SCANNING

APPLICATIONS

CUSTOMISED PATH PLANNING

AUTOMATED PATH PLANNING BY AI

HYBRID DESIGN

PRINTING ON A MOLD : SURFACE COAT3D

ADDONS

MOLD FABRICATION: Milling

ALGORITHMIC DESIGN

SENSING

MOLD FABRICATION: Assembly

GENERATIVE DESIGN

RECYCLED THERMOPLASTICS

ADDITIVE VS. SUBTRACTIVE

ROBOT VS. CNC MACHINE

Introduce as conclusion of robot vs cnc

THERMOPLASTICS

INTRODUCTION

HYBRID TOOL

Physical Properties of FDM