OSTRA (One Shade To Relieve them All)

Team OSTRA is conformed by Daniel Aristizábal, Ece Sel, Shashvat Shrotria and Eloy van Kessel. Four architects from different countries, continents and professional backgrounds but with one objective in common: design a Convertible Urban Shade that aims at ameliorating the urban context.

Throughout this booklet, the team’s design and prototype construction journey is documented consisting of tests, error rounds going back and forth, but also some wins and lots of laughs.

Daniel

Shashvat

Ece Eloy

2.1

1.1

1.3

1.4

2.2

CHAPTER INTRODUCTION

1.1 ABOUT

1.2 BRIEF BACKGROUND

1.3 PROBLEM STATEMENT

1.4 DESIGN VISION

1.5 ELEVATOR PITCHES

1.5 SITE STUDY

1.6 SOLAR STUDY

1.1 ABOUT 1.3 PROBLEM STATEMENT 1.4 DESIGN VISION

Bucky Lab design studio is a hands on master’s course offered by the Technical University, Delft. This course gives the students the opportunity to design, develop and finally build architecture and building construction related prototypes.

1.2 BRIEF BACKGROUND

The initial 4 weeks were assigned for individual exploration of concepts and strategies to develop convertible urban shades. Once the elevator pitches were presented, the students had a choice of either making groups with people having similar design approach or having a design scheme that would be interesting to work on.

Over the past few decades, the world has experienced a drastic climate change that is now perceived as the biggest challenge for humanity. With an increase in the temperature at an alarming rate, outdoor conditions have become harsh for carrying out public activities. Therefore the search for new and innovative strategies to make the streets more comfortable and usable began after the introduction of Bucky Lab studio. All the students were initially given the task to develop individual concepts of convertible urban shades. These urban shades will be responsible to reduce the urban heat island effect by providing urban shade during the day and radiative cooling during the night. This can only be achieved by providing a mechanism that will facilitate the opening and closing of the temporary structure. Hence, the structure has to be light, demountable, and easy to use.

During the summer, spending time in open squares can be stressful without a sunshade. Concrete bollards, commonly deployed in various public places, have the potential to become seating spaces. However, the absence of a sunshade defeats that purpose. Therefore, the team proposes a solution that can be installed on the bollards outside Delft Central station to make them more usable as well as tackle the problem of the urban heat island effect. An umbrella is the first thing that comes to mind, but that too has its limitations. It is flimsy with respect to material and often incoherent with the context.

To overcome these shortcomings, this project brings forward 3 major design strategies that can be implemented to create a temporary shading structure.

Adaptability: The shape of the geometry is conceptualised in such a way that it adapts to the smaller altitude angles during long summer days. The overhang is longer towards the south and west direction to block the sun rays during peak hours.

Sturdiness: The aim is to install a temporary sun shade which is sturdy and can withstand harsh weather conditions.

Context utilisation : Lastly, the design vision also incorporates utilisation of the existing hardscape elements such as the concrete bollards.

Over UV exposure

Overheating

Lack of sun shading

Uncomfortable

Headache

Heat exhaustion

Allergic reactions

Sunburn

Need for temperature control

Lack of comfortable waiting spaces for passangers

Urban heat island effect

Staying indoors due to the temp.

Aesthetically appealing places

Heat stress

Shades a large amount of area

Enables people to wait comfortably

Creates a gathering point

Make use of the existing hardscape

Quickly openable

Easily operatable

Convertible

Aesthetically appealing

Strong enough

Deployable

Durable

Radiative cooling during night

Light and healthy material choice

Increases outdoor usage

What are the current problems? How it can be solved and with what ? What are the outcomes of the design? sun healthy

Durable

1.5 INDIVIDUAL ELEVATOR PITCHES

FAN SHADE

FAN SHADE

FAN SHADE

ECE SEL - 5703581

ECE SEL - 5703581

Single unit:

Single unit: made of Fabric & Timber

open - close :

mechanism

1.6 SITE STUDY

The location of the project is the Delft Station, which is located in the heart of the city and is a heavily frequented area, as it serves as a hub for all public transportation routes in Delft.

On the south side of the Delft Station, there are several bollards installed to act as barriers that restrict vehicular access and ensure the safety of individuals. These bollards also serve as seating areas for individuals awaiting public transportation and as meeting points. However, with the increasing temperatures each passing year, especially during summer, waiting in the open area with limited shelter or coverage can be quite uncomfortable. Therefore, the project aims to utilize these existing bollards as a foundation to provide shade for individuals and create a more comfortable environment; while making use of the existing product on the site.

Location: Delft, Netherlands

Foundation: Bollards in front of the station

Bollards

Gemeente / Train Station Restaurant Student Hotel

1.7 SOLAR ANALYSIS ON SITE

To determine the sun-shading with maximum efficiency, it is essential to understand the solar movement within the chosen site and the degree of shading generated by surrounding structures such as buildings. Therefore, a solar analysis of the site was performed utilizing the online program called “Andrew Marsh.” To do that, a simplified three-dimensional model of the Delft station and the surrounding buildings was modeled and imported into the online platform. Afterward, for three important seasons, spring, fall, and summer the shadow study has been conducted.

As a result of the analysis, it can be concluded that during the summer months, the Delft train station blocks the sun and creates a shadow on the bollards around 4:30 pm during the rush hour. On the other hand, in the earlier times during the summer, the bollards experience a significant amount of sunlight. Furthermore, during spring and fall, the bollards still receive sunlight, but the temperature is not as high during those seasons

The images on the right side of the page demonstrate the solar angle, which should be considered during the design of the convertible urban sun shade, and the determination of the angle and length of the sun shades

Shadow Analysis 1: 21 Jun 2022 at 12pm

Shadow Analysis 2: 21 Jun 2022 at 5 pm

Shadow Analysis 3: 21 Mar 2022 at 12pm

Shadow Analysis 4: 21 Sep 2022 at 12pm

1.7 SOLAR ANALYSIS ON SITE

Daily Solar Data Analysis in the Netherlands | Latitude: 52.0106480°; Longitude: 4.35745239°

Reference: Adrew Marsh 3D Sunpath

2CHAPTER RESEARCH

2.1 CRITERIA

2.1.1 SOFT CRITERIA

2.2.1 HARD CRITERIA

2.2 MATERIAL RESEARCH

2.2.1 RANGE OF OPTION

2.2.2 SELECTION

2.3 GEAR RESEARCH

2.3.1 SPUR GEAR

2.3.2 INTERNAL GEAR

2.3.3 BEVEL GEAR

2.3.4 WORM GEAR

2.3.5 BEVEL vs. WORM GEAR

2.4 BOLLARD ANALYSIS

2.5 WEIGHT ANALYSIS

2.1 CRITERIA

2.1.1 SOFT CRITERIA

Make use of existing foundation; In front of the train station of Delft are twenty-one anti-terror bollards situated, designed to look like seats to wait for the coming buses. Aim of this project is to use these bollards as the foundation of the shading.

Manually useable; the shading will be manually closeable so that people can choose when to close down the system.

Lightweight fabric; the fabric used for shading should have an almost negligible weight in order to make the construction of the urban shading as slim as possible.

Convertible; during the night the system will be able to close down in order to allow fresh air to cool the area beneath the sunshading.

Provide shade during the day for people standing around the bollard; Aim of this project is to provide shade for people waiting for their bus. Standing next to these bollards will offer unique shading throughout the day for passangers standing in the public square of Delft. Convertible; during the night the system will be able to close down to allow fresh air to cool the area beneath the sun shading.

Easy to operate; the system will close in such a way that it is easy to comprehend and straight forward to use.

Construction as light as possible; the construction of the urban shading should be as light as possible while still maintaining enough strength to function.

Variation of fins; the rotating system contains a variety of fins casting a unique shading pattern.

Durable; the shading is able to exist for a long time without significant deterioration in quality or value.

2.1.2 HARD CRITERIA

Attached to the center of the concrete bollards; the fins of the shading should be attached to a center pole which is then connected to the center of the concrete bollards in such a way that sitting on the bollard is still possible.

Opened in less than a minute; the shading should open in such a way that it takes less than 1 minute from closed to open state.

At least 2.2 meter of free height at the lowest point; the shading should feel safe to use without concern of bumping your head.

Rotational opening; the multiple fins of the urban shading should open through a rotational motion.

Lightweight material (to be calculated); the material of the fabric used for the shading should have a maximum of 250 grams per square meter.

At least 3.0 m wide diameter; the diameter of the fins of the biggest fins should be at least 3.0 meter to provide enough shading to feel comfortable. Shades touch each other

The biggest side orientated to the South; the biggest of the fins should be orientated to the South in order to maximize the shading capacity of the urban shading.

2.2 MATERIAL RESEARCH

The structure of the Ostra sun shade should be light enough to have a large span, enabling an efficient amount of length for the shadow. However, it should also have enough stiffness to avoid bending. The materials shown below comprise of these characteristics where recycled materials, plastic or used wood, natural or artificial fibers might be a solution. In addition to the structure, the rotating elements will be filled with a material that will ultimately provide shade.

2.2.1 RANGE OF OPTIONS

1. Graphene: With a density of just 5%, can have strength 10 times that of steel. Might be expensive to get.

temperatures and low thermal expansion. Is relatively expensive but not as graphene.

5. Recycled Wood:

Material made from recycled wood is five times stronger than naturalwood and can be made from any timber product, including shavings and sawdust.

2. Carbon fibre:

Lately being used in sciences and sport fields due to its many advantageous properties, such as high stiffness, strength, and chemical resistance, as well as its ability to tolerate high

3. Steel: Very common to use in urban equipment of minor scale and urban furniture. Its major advantage is durability.

4. Aluminium: Highly useful in producing light structures for outdoor settings. Lightweight, strength, and is easy to work with. Resistant to corrosion and requires minimal maintenance.

4. Plastic Fibres:

Made by recycled polyester, mostly used in hightech greenhouse agriculture, planting, etc. Have a good look and works fine for sunshade & rainproof. Its life time is long and easy to find and install.

6. Hemp Fibre:

Hemp plant-derived natural fibres are strong, biodegradable and lightweight, making them ideal reinforcements for composite materials. They also have inherent mechanical, thermal and acoustic properties.

2.2.2 FINAL SELECTION

As a result of comparising different materials, steel was the ideal material for the principal vertical structure of OSTRA, which will support the fins and the rotational system. For the fins structure, the carbon fibre was the optimal choice due its stiffness and lightness, for the element which will connect the fin and the column, called joint, aluminium was the perfect selection for its versatility and easy way to mold. Lastly, for the final cover, the hemp fibre was selected as a material but opting for a textile made out of it. The lightness of this element is crucial in order to not add unnecessary weight to the entire structure which will made the rotation harder.

2.3 GEAR SYSTEM

The rotational opening of the urban shading asks for some sort of gear system that rotates the central joints to which the fins are attached. Different types of gears were researched in order to find the correct solution for this particular design.

2.3.1 SPUR GEAR

A spur gear is a type of cylindrical gear, with axes which are both coplanar and parallel, the teeth are straight and orientated parallel to the axes. It is possibly the most simple and common type of gear, it is easy to manufacture and suitable for a big variety of purposes.

Pros:

Transmission efficiency; spur gears have a high power transmission efficiency, making them ideal for preserving efficiency in some types of systems.

Gear train; multiple spur gears can be used in series (referred to as a gear train) to achieve large reduction ratios.

Straightforward design; a spur gear has a straightforward design which makes it easy and cheap to manufacture.

Cons:

Noise production; the method of tooth meshing causes high stress on the gear teeth and thus high noise production. Therefore they are most commonly used in lower speed applications.

Stress; spur gears take up a lot of stress, so they are not ideal for heavy loads. If they do take up heavy loads, they will experience a lot of wear and will not be very durable

Pros:

Same rotation; while when two simple spur gears are used it changes direction of rotation, with an internal gear the rotation remains the same when pairing it with a spur gear.

Short center distance; the centre distance of the two gears can be shortened by using this type of gear system. This makes a space-saving design possible.

Better protection; when designed properly, an internal gear offers better protection against dirt due to the internal teeth.

Lower wearage of gears; when an internal and external gear touch it has a large contact area, which results in a lower tooth load and therefore a reduction in the wear of the gears.

Cons:

2.3.2 INTERNAL GEAR

An internal gear is a gear with its teeth cut in the internal surface of a cylinder and meshes with a spur gear. An internal gear wheel is sometimes simply called a ring gear

Expensive; because this type of gear system is only used in some special cases the production is expensive.

A bevel gear system contains of two gears where the axes of the two shafts intersect and the tooth-bearing faces of the gears themselves are conically shaped. Most commonly the gears are mounted on shafts with an angle of 90 degrees between them. These gears are used to transfer horizontal energy to vertical energy.

Pros:

Same rotation; while when two simple spur gears are used it changes direction of rotation, with an internal gear the rotation remains the same when pairing it with a spur gear.

Short center distance; the centre distance of the two gears can be shortened by using this type of gear system. This makes a space-saving design possible.

Better protection; when designed properly, an internal gear offers better protection against dirt due to the internal teeth.

Lower wearage of gears; when an internal and external gear touch it has a large contact area, which results in a lower tooth load and therefore a reduction in the wear of the gears.

Cons:

Expensive; because this type of gear system is only used in some special cases the production is expensive.

Basically, a worm gear is an angled and curved teeth screw that is butted up against what looks like a standard spur gear. An electric or manual force applies rotational power via the worm gear, the worm gear then rotates against the spur gear. This way the plane of movement changes due to the position of the worm wheel, besides this, the rotational movement also rotates by 90 degrees.

Cons:

Lubrication; with a worm gear, sliding motion is the only transfer of power. As the worm gear slides across the teeth of the spur gear, it slowly rubs off the lubricant, until there is no lubricant left between the teeth, and as a result, the worm gear rubs at the metal of the wheel and slowly creates more resistance between the two gears.

Pros: High reduction ratio; A worm gear has a great reduction ratio, it either reduces the speed of the gear or create more torque in the rotation of the gears.

Inability to reverse the direction of power; for this project the main reason to use this gear is the inability to reverse the direction of power, meaning: the worm gear can only rotate the spur gear and not the other way around

Change direction; this gear makes it possible to change the operating angle.

Taking into account the pros and cons of both the worm and bevel gear, for this project the worm gear comes out on top. The amount of precision needed for mounting the bevel gear is too high, especially for making the prototype in the building weeks. Besides that the worm gear has the inability to change direction of power between the gears, which is needed for this project.

2.3.4 WORM GEAR

2.2.5 BEVEL GEAR vs. WORM GEAR

2.4 BOLLARD ANALYSIS

Bollards are protective and visual architectural elements that prevent the entrance of certain vehicles by emphasizing the boundaries of traffic pathways, mainly to protect people and properties.

They are prevalent in modern urban environments and come in different sizes. Despite the variety of materials that can be used to make bollards, the most common materials are concrete, metal, stone, or plastic. These materials are selected due to their ability to withstand high-force impacts

To acquire a comprehensive understanding of the bollards, which will serve as the foundation for the shading unit, YTER Company, the manufacturer of the bollards, was contacted. Through this process, a plethora of information was obtained, including details on different bollard types, technical specifications, information on ground attachments, and the materials used for finishing. This information was crucial in informing the design and selection of the most suitable configuration of the OSTRA sunshade. Contact person: Rafael Malaga (SP).

After consulting with the fabrication company of the bollards and conducting research on their structure and properties, it was determined that the average weight of the bollards located in front of the Delft station is approximately 200 kg. The ground fixing of these bollards is also confirmed. As a result, it was concluded that adding a column to support the design of the OSTRA sun-shade on these bollards will not pose any issues or complications.

Th Bollard on site

As specific information was not obtainable, the data presented below has been sourced from the catalog of the bollard fabrication company.

Company: YTER Comapany

Materials: Concerete

Dimensions: Upper diameter : 80mm

Lower diameter : 60mm

Height : 80mm

Weight: Approximately 200kg

Reinforce: Reinforced with steel thread bar M20

Detail: Polished & covered with anti-decay coating

Installation: Drilling a hole to the ground, filling the hole with anchors and then introduce the bollard and thread bar.

Types of concrete bollards

connection to the ground

2.5 WEIGHT ANALYSIS

Joints:

CHAPTER ENGINEERING AND DESIGN

3.1 GEAR SYSTEM AND BALL BEARINGS

3.2 SHADING ITERATIONS

3.3 DECISION ON TILTING

3.4 FIN SEQUENCE

3.5 SHAPE OF FINS

3.6 DESIGN DEVELOPMENT THROUGH MODELS

3.7 SCRIPT

3.1 GEAR SYSTEM & BALL BEARINGS

3.1.1 GEAR SYSTEM

The main design characteristic of this Urban Shading is the central pole to which the 12 fins are attached. In the initial concept, 12 rings are stacked on top of each other around the central pole. Then, the 12 fins are attached to these rings which rotate around the central axis separately (see figure x). In order for this concept to work a gear system had to be designed for this specific type of rotation.

When brainstorming about this rotating mechanism, a main design issue came up: how can every fin move individually with such a small amount of space available in the pole? In addition having enough strength to keep the pole from buckling, bending, or breaking. The idea came up to move only the lowest fin and “pull” the rest of the fins with this lowest fin. This also made it easier to handle manually from the lower part of the pole. When this idea was made final some steps were taken in the design process to get to the final design;

1. The fins are rotated by only rotating the lowest fin, soon the design consisted of a handle on hand level that drives a worm gear inside of the pole this worm gear makes it so that the handle rotates the fins and not the other way around. This worm gear drives in its turn a spur gear which rotates a pole that moves this force up to the plane of the first fin, where another spur gear is located. This spur gear gives the right rotation and plane for the first fin to be rotated. (see figure x).

This step was made very fast in the process and the team believed this would work and give the desired rotation to the top part of the pole. Then the question came up of how can this system rotate the fins from the central axis while also having the structure, the pole, in this same axis. After a lot of sketches, research, and talks with Marcel and Nadia, the team came up with the idea of an internal gear, so that the central axis allows space for the structure.

2. The spur gear drives an internal gear which is connected to the lowest joint; the lowest fin starts rotating.

The first fin rotates, and now the team had to figure out how the next sequence of fins is going to rotate from this first one. A lot of options were discussed: for example hooks on the fins to catch the hook on the next fin to make it rotate or rails on the fin structure where a wheel rotates in until a certain point where it is stopped and the next fin starts rotating. The “stoppers”, as called in this project, on the fin itself were quite a challenge because they added undesired weight to the fins. At a certain point, Nadia came up with the idea to put the stoppers inside the joint and make it part of the mold design. This idea was worked out further

3. When the first fin has rotated 30 degrees, a stopper inside the joints’ H-section ‘‘catches’’ the next joint, and that fin also starts rotating, then a stopper on the next joint catches the joint on top of that, and so on; all the fins rotate after one another.

Figure x: Sketch of initial ring design

Figure x: Sketch of exploded gear system

To ensure the joints around the pole are able to rotate without having a lot of resistance, the team had to figure out how to connect the joint to the pole to have enough stiffness while also rotation is not hindered. After some talks and discussions with Marcel, the objects we needed were quite clear: ball bearings.

Not knowing how ball bearings worked the team had to do some research into the different kinds of ball bearings available. Explanations of Marcel made this part easier and the team concluded this project needed two different kinds of ball bearings: a thrust ball bearing and a deep groove ball bearing.

Thrust ball bearing:

Thrust bearings accommodate loads that act predominantly along the axis of the shaft; axial loads. It consists of two shaft washers which are separated by balls; this makes it so that the two washers can rotate relative to each other without resistance. In this project the internal gear and the lowest joint are attached on top of the top washer, see figure x.1. The lowest washer is attached to the pole. The spur gear can then rotate the internal gear which makes the top washer (including the joint) rotate.

Deep groove ball bearing:

Deep groove ball bearings are robust in operation, requiring little maintenance, can operate at high speeds and accommodate radial and axial loads in both directions. In this project these ball bearings need to accommodate axial loads, see figure x.2. The ball bearings are jammed inside the casted joints, attaching the outside washer of the ball bearing to the joints by resistance. Then the ball bearing and joint are stacked around the central pole and put on the bearing flanch. Now the outside washer rotates relative to the inside one making the joint rotate without resistance.

Figure x: Sketch of section of gear system including ball bearings

Figure x: 4310 ATN9 Deep groove ball bearing

Figure x: 51220 Thrust ball bearing

Figure x: Diagram of gear system including ball bearings

Axial loads

Top washer

3.2 PLACEMENT ON BOLLARDS

To determine the optimal configuration of the OSTRA sun-shade, a shadow evaluation was conducted utilizing a 3D Sun path website. Six different iterations were examined.

The primary criteria used to evaluate and select the most suitable configuration amongst these six iterations include;

a. The aesthetic impact on the overall site and the presence of an over-crowded appearance

b. The potential for one shade to obstruct the adjacent one

c. The distance between sun shades.

d. The necessity of tilting the sun shades

e. The orientation of the longer fin in relation to the site’s sun path

Configuration 1: Every bollard is occuped.

Configuration 2: One of the two bollard

Configuration 3: Two of the three bollards

Configuration 4: Three of the four bollards

Configuration 5: One of the two bollards but the inclination is different than 2 and 6.

Configuration 6: One of the two bollards but the inclination is different than 2 and 5.

Decision: After conducting the shadow analysis, Configuration 2 was determined to be the most efficient design iteration. This configuration demonstrated a higher level of efficiency by creating a convenient amount of shade without obstructing the adjacent sunshade, and also maintaining an appropriate design aesthetic. After, further analysis and calculations (presented in Section XX), it was determined that tilting the sun shade was not necessary.

Tilting the Sun-Shades

The initial design was including a feature where individual units can be tilted to enlarge the shadowed area underneath the design.

To evaluate if that’s a great idea, further calculations are made considering the sun angle in the specific location, with different tilt levels. Mainly, hand calculations are done which can be seen on the right-hand side of the page and their illustrations are below.

However, upon further examination and analysis, it was determined that the implementation of tilting will not create an efficient amount of shade. This conclusion was reached since achieving a sufficient level of shading through tilting would require an angle greater than 30 degrees, since the sun angle in the Netherlands does not exceed 80 degrees.

Furthermore, the implementation of tilting had the possibility of introducing additional difficulties. For example, the design had to be higher for the lowest edge of the fin not to go below the eye-level to not create a safety risk. Additionally, a more complicated mechanism would be required to operate the design.

Small to large:

The initial design had the lowest fin at the bottom and the largest on top. As the idea was to rotate just the lowest fin to create the helical movement, the team realized something. A small object doesn’t have the necessary strength to move objects bigger than its size, To do that, more rotation in the driving gear should be incorporated to produce more torque. But that will increase the strain on the user and make it less efficient. A smaller fin the bottom also means that the larger shadow will casted away from the bollard and not closer to the bollard. Thus the sequence of fins needed revision for a better design scheme.

to small

Once the largest fin was placed in the bottom, no complex gear system was required to produce extra torque for rotation. A larger shadow will be cast close to the bollard thus making it more usable. The previous sequence of fins also proved to be unstable during nighttime when the whole assembly is aligned. After reversing the order, the weight distribution will also prevent it from toppling over when all the fins are brought together, one on top of the other.

Large

Evolution of the design

The initial design consisted of a triangular frame structure for individual fins. The team soon realized that this design needs to be optimized to compensate for the extra weight. A few iterations were thought of using a cross-bracing system, tie beams, and even cables but all seemed to have close to negligible effect on the weight distribution. Thus research on new shapes had to be done that are lightweight and can help the design to be more economical.

1:20 scale model

Once established that the initial design needs modification in terms of weight distribution, the team did a study of lightweight structures. First, a windsurf was studied because of its lightweight carbon fiber structure and its construction detail of supporting the fabric. A few ideas were sketched out that made the team aware of the complexities that come with the wind-surfs. The team wanted something more simple in terms of construction and light weight.

Wind- surfs

Evolution of the design

Kites are lightweight structures that inspired the group to finally modify the fin design. The fin will now consist of a central spine that will be connected to the secondary spine structures. The frame will support the fabric on top with the help of cables that will be tied to the spine. the initial design also had provision for external rails that will direct the rotation movement. Rail in the bottom fin will catch the stopper on the top fin to move the assembly in a sequence.

3.6 DESIGN DEVELOPMENT THROUGH MODELS

After sketching, discussing, and thinking everything was on the correct path, came the moment to model the ideas. The working models are not pretty and have fine finish, they do not need to be. Their principal objective is to show errors and quickly test all the possible solutions.

The first model used wood materials for the structures and butter paper as fabric. Issues such as how the hitch between the fins would work or the weight of the structure, which eventually would make the model collapse due to the imbalance, began to arise.

The second model used different materials for the most important components. The bollard was done with a weight inside its cover to represent the resistance to movement due to the fins. The pole used a thicker rounded wooden stick. The joint between the fin and the pole was made with plastic to represent its lightness. For the fin, the improved design, shown in the previous section, was modeled and the structure was made with light plastic. The fabric was represented by a thicker paper and in an attempt to explore colors, an orange paper was selected, but it was glued backward.. at the end the bright color seemed a good option. Not bad after all.

Also, this model was used for a fast shadow study, some criteria were reafirmed and others were revised.

After the study on 1/25 scale was complete, a deeper study of the mechanism was needed. The joint was one of the most difficult parts to solve, as this element contains the ball bearings, and the stopper and is the connection between the fins and the pole. Is the part which binds everything.

The first model was made on a 1/2 scale, using MDF as material, and also, the principal structure from the fin was included. Here, the shape was already set, but other design decisions as where to locate the stopper or how would the fins’ principal structure would fix to the joint were not solved yet. This model gave us the opportunity to detect these issues and solve them.

The second model was made on a 1/10 scale, and as we already knew what it was looking like, it was done smaller. This one shows solutions to problems detected on the first try. The stopper was located in the inner channel with a 30° motion range and an extra plate was included to have the necessary space to screw the fins’ principal structure to the joint.

In addition, the gears were modeled to test the mechanical system. The ring represents the first joint, with a ball bearing, which will be the one that moves the rest. These pieces were done by using MDF and laser cut to have a precise cut for the gears teeth

As can be seen in the pictures, laser cutting and handmade techniques for the fabrication of the models were used. Each one of them with a different purpose and depending the quantity of time available.

3.7 DESIGN DEVELOPMENT THROUGH SCRIPT

To further understand the rotational movement of this geometric form, a 3-D model was generated through an algorithmic script in Grasshopper, a visual scripting software used as an extension to Rhinoceros. From the previous sections, it is clear that OSTRA is a spiral shaped structure that rotates in a sequence.

The base model was generated based on a spiral shape that is asymmetrical in shape with a maximum diameter of 5 meters and a minimum of 3 meters. Once the curve is created, lines are constructed connecting 12 points on the curve to the center of the circle.

As the lines are obtained, they are converted into rectangular blocks that form the spine of the fins.

The problem to be solved was creating a sequence of movement that allows the fins to move after every 30 degrees of rotation. The script used and situation, where the top fin moves only once the bottom fin, completes a 30-degree movement from its initial position.

DESIGN DEVELOPMENT THROUGH SCRIPT

4 CHAPTER TECHNICAL

DRAWINGS

4.1 DESIGN

4.2 BUILDING WEEK

Every design can look great on paper or in renders, but it is also important that it works and can be built. To achieve this, technical plans are necessary, as they are the means by which the constructor can make the design a reality.

In this case, two types of plans were made: the design technical plans of the complete object and the technical plans for the prototype construction that would be built in the following weeks. The difference mainly lies in the materials that are detailed and the scale used.

4.1 DESIGN TECHNICAL DRAWINGS

Thousands of hand drawings were made in the design process of OSTRA, but also work technical plans accompanied this stage, which helped to give scale to the ideas. After the design was completed, the final technical plans were made and are shown below.

The technical file consists of general top views, a section of specific parts, and a top view with sections of the most important elements.

1. General Top Plan (open stage):

In this plan the main general dimensions are shown, as the distance from the center to the farthest points. Also, every fin lenght is detailed, for this reason the open stage of the object was considered appropriate. Finally, the materials and thickness of the most important elements which can be seen are shown; some of them appear in a dotted lines as projections.

GENERAL TOP VIEW PLAN

OPEN STAGE

ESC.: 1/25

To give more information, color was included to the plan. The gradient color gives depht to the drawing, which can help to understand which fin are aboved and at the bottom.

All the fins are shown one on top of the other. Also, the bollard can be seen in the background.

GENERAL TOPVIEW PLAN

CLOSE STAGE

ESC.: 1/50

Distance from the ground to the lowest and heighest fin are shown, as the handle’s height.

The top part of the object is where almost all of the mechanism for movement for the

happen.

2. General Top Plan (close stage):

4. Section A:

fins

3. General Section:

5, 6. Joint plans (type 1):

One of the biggest challenges in the design was the joint between the pole and the fin, which also needed to move. For that purpose ball bearings were used to make the rotation possible.

The design have two kind of joints. The first is attached to the gear, the second type are above and repeats eleven times.

7. Joint plan (type 2):

The design contemplates a casting fabrication for this piece. For that matter, in this plan all the dimensions to make the mold for the joint are shown.

PLANS

JOINT PIECE - TYPE 1

ESC.: 1/5

JOINT PIECE - TYPE 2

ESC.: 1/5

8. Detail Section 1: A close view in section of the joint showing the dimension and also how the stopper would work.

9. Detail Section 2: Other section of the joint showing the longest part which will be in contact with the fin.

4.2 BUILDING WEEKS TECHNICAL DRAWINGS

For the materialization of one of the models that were done, plans were also needed. The following ones correspond to a ball bearing production, part of the rotational system. One section and several plans of two levels and the middle ring were drawn These drawings were done after studying the material that would be used and the available tools. During the construction, changes were also made.

1. Thrust ball bearing:

Left: Ball bearing plan view. Bottom: Ball bearing section. Right: Middle ring plan view.

2. Groove ball bearing:

Top: Ball bearing plan.

Middle: Ball bearing section.

Bottom: Section showing the parts which conform the channel for the ball bearing.

BALL BEARING FOR JOINT TYPE 1

ESC.: 1/5

BALL BEARING FOR JOINT TYPE 2

ESC.: 1/5

BALL BEARING FOR JOINT TYPE 2

ESC.: 1/2

PLANS AND SECTION

PLANS AND SECTION

3. Section for 1/1 Model:

The prototype of the mechanism was tried to be represented, before the actual building weeks, in a section with all its components. Some of the materials for the elements where not decided yet.

1. 1 Hollow Pole (material unknown) - metal or PVC. D=30cm. H=40cm.

2. 1 Hollow Pole (material unknown) - metal or PVC. D=15cm. H=20cm.

3. 1 First Joint (Detailed below)

4. 2 Second Joints (Detailed below)

5. 1 Rod (material unknown) connection between worm gear and spur gear - metal or PVC. D=1cm. H=40cm.

6. 1 Rod (material unknown) for the handlemetal, wood or PVC. D=4cm. H=7.5cm.

7. 1 Worm Gear System. 3D printed. (Detailed below) H=29cm.

8. 1 Rod (material unknown) connection between handle and worm gear - metal, wood or PVC. D=1cm. H=5cm.

9. 1 Spur Gear (upper part). 3D printed(?). (Detailed below).

10. 6 Support Triangles. (material unknown)metal or wood. W=1.5cm. H=2cm. Thickness: as thick as possible.

11. 3 Separation Rings. (material unknown)metal or wood. IR=15cm. ER=18cm.

SECTION 1/1 MODEL ESC.: w/e

5CHAPTER BUILDING

WEEKS

5.1 TARGETS

5.2 BUILDING WEEK PROGRESS

5.3 GANT CHART

5.4 PHOTOS

5.1 TARGETS: 1:1, 1:2, 1:10

To give a good impression of how the OSTRA project looks and works, several scales of the project were built. Target beforehand were three different scales:

1:1 model, this scale is all about the rotational mechanism. How does is it open and close and what happens inside of the structure?

1:2 model, the 1:2 model is proposed to show of the fin structure and the attachment details of fabric to the fin and fin to the joint.

1:10 model, this scale will show the whole structure and give an impression of how the project will turn out to be.

5.2 BUILDING PROCESS WEEK 1

The first day was the introduction day, where several experienced people showed the powertools to the students and how to handle them with care.

On tuesday the group was excited to start and knew it had a big task to get all of the ball bearings and joints finished on time. After some quick discussion and question with and to Marcel, the router was taken and a lot of circles for the ball bearings were made. The 1:1 model required one thrust ball bearing and two groove ball bearings. The thrust ball bearing consisted of two separate rings and the groove ball bearings of four rings each.

So, a lot of circles in not so much time had to be delivered. In turns the group took up the router so the process did not stop, the bit was rotating in overtime and got so hot it burnt some of the circles and the bit had to be thrown away, unfortunately... While this process was going on drawings were made for the 1:2 joint, which was going to be made by using the Shaper tools. Wednesday arrived and the group needed the whole day to finish the circles for the ball bearings. While two people were working on the rings, the other two finished the 1:2 joint.

After two very productive days, thursday was a day off; the group was a bit lost and did not really know what to do. Drawings for the shaper took a lot of time and besides getting the lasercuts for the 1:10 not a lot of progress was made unfortunately. At the end of the day a plan was made so the group would not get stuck again.

On friday the first joint for the 1:1 model was made as well as the base for the 1:10, after an intense first week it was time for the weekend.

Most of the products were finished starting the first week, this week would be finishing up and assembling the products in order to be finished on Wednesday.

On Monday two shapers were used all day in order to finish the joints for the 1:1 model. Taking turns the team managed to get them right, a few mistakes were made because of the repetitive cutting of the joints. These mistakes were small and the team was able to get them right afterward by using sandpaper. In the evening the gears were printed so we could assemble the gear system on Tuesday. To get this system working the team had to improvise a bit, the main issue was the round pole where the gears had to be attached to. After some trial and error with the different types of gear, the team managed to get them tight and working. Until this point, the product was never assembled and the team did not know yet if the model was going to work. The process in which the product had to be assembled could only start when every individual product was done. On the final day, all of the products were done and the different models had to be finalized. Most important was the 1:1 model, the assembly of the model went quite well. The main problem was that the ball bearings had some imperfections which led to crooked angles and therefore the angle of the joint was crooked as well. The team took 5 mm of tolerance between the joints but this was not enough in the actual model.

The different joints stacked on top of each other were touching and this led to resistance between them. When rotating the lowest joint the joint on top of that one started to move because of this. To solve this issue a few marbles were put inside of the H-section of the joints in order to give some extra tolerance between them. This solved the issue of the resistance but was of course not the perfect solution. The team had no time to solve this in another way so this solution was chosen. In the end the 1:1 model rotated as envisioned, the 1:2 gave a great representation of the fin structure and the 1:10 model looked very cool. Satisfied the OSTRA team enjoyed some nice snacks and beers with the rest of the Bucky Lab colleagues.

Ball bearings and gear system Joints

Cutting the pole and assembly

1:2 Fabric Joint Structure

1:10 Lasercutting the fins

Base and pole Assembly

5.3 GANTT CHART

CHAPTER FINAL PRODUCT

6.1 RENDER

6.2 SOUTH ELEVATION

6.3 AXONOMETRIC VIEW

6.4 PHASES

6.5 ASSEMBLY DETAIL

6.6 EXPLODED DETAILVIEW

The render shows how the project is envisioned by the team in front of the Delft Central station. It provides shade throughout the day and it can be operated by individuals belonging to all age-groups.

The elevation shows how OSTRA reacts to its context. As it has minimum 2.4 meters clear height, it allows people to stand next to it as well as sit on the bollard. OSTRA makes the bollards outside Delft Central station more usable as people can now wait for their bus in the shade, The pole also give back rest for people sitting thus making it more ergonomical.

OSTRAs are placed on alternate bollards. This scheme was conclusively chosen after running real-time sun solar simulations. With this arrangement, there are always pockets of shaded areas either close to the bollard or onto the next bollard. Alternate OSTRAs also make the place look less clustered from eye-level thus not making it overwhelming for people using it.

Fin

Cast Aluminium Joint

Inner column 150mm Dia.

Exoskeleton 300mm Dia.

Handle for Gear system

Existing Concrete bollard

Ball bearings 200mm(outer dia.) 150 mm(inner dia.)

AL Stopper

Cast Aluminium joint

5X5 mm channel section

Rail channel

25mmX15mm

Hemp fabric 5mm

Cast Aluminium joint

5X5 mm channel section

Mortise and tennon AL joint

20mmX15mm

Fin primary spine

Carbon fiber 25mmX40mm

Thrust ball bearing

300mm(outer dia)

240mm(inner dia)

Spur gear 40mm Dia.

10 mm Rod

Worm gear

Inner pole

150mm(outer dia)

Handle

Steel cables 3mm

Eyelets 3mm

Steel cables 3mm

Steel hooks

Spilcing plates 3mm

Screws 5 mm

CHAPTER REFLECTION

7.1 GROUP REFLECTION

7.2 FUTURE CONSIDERATIONS

7.3 INDIVIDUAL REFLECTION

Who are we?

We, the group of “OSTRA”, are MSc. Building Technology students of TU Delft, coming from three different continents around the world.

During the initial phase of Bucky Lab, we all shared similar ideas on a sunshade which was designing a manually operated sunshade supported by a pole, addressing issues of high temperatures and the urban heat island effect. We came together and chose a design that had a strong starting point, a great location in Delft, in the Netherlands, and then started brainstorming to improve it. Having that purpose as a team, our journey as OSTRA had begun!

Our diverse backgrounds enabled us to come up with unique concepts, references, and ideas that would not come to others’ minds. We always enjoyed our company, and learned from each other, not just academic stuff but also about our cultures. Eloy made us familiar with the local Dutch culture and became the tourist point whenever we needed him; Daniel made us familiar with the amazing natural habitats and places of Peru; Shashvat taught us all the colorful and joyful Indian Festivals and his rockstar talents; and Ece made us familiar with the delicious Turkish cuisine and increased our curiosity of Istanbul to see both continents at once!

Throughout the Bucky Lab, we tried to keep our meetings 1-2 times a week and 1 time during the Bucky Lab studio. During each meeting, we never forget to enjoy our coffee sponsored by the person who came latest to the group meeting! We even learned who we liked and what type of coffee, haha!

All of those made our design process more stronger and fun. We always had a healthy discussion, where we were able to discuss our ideas freely, and respectfully and come up with decisions altogether. We have understood the importance of having constructive feedback from each other, which we believe made us great groupmates and made our design stronger.

Throughout the process, all of us put in our effort equally, always asking “how can I help?

That’s us! But, you might still wonder where our unique group name “OSTRA” is coming from. So, there it is

*A small note: Shashvat wanted to say “Rule” but as the others, we wanted to keep it low-key! Haha

Design Week Process:

During the design processes, we have focused more on how to operate our system and the shape of our design to optimize the shade as much as possible. Learning about different gear systems and ball bearings became the most interesting part for us, which we ended up even constructing! We made several working models, using different materials depending on the objective of each one. Despite the good communication we had between us, we started with a fine model of our joint, it cost a lot but was not entirely necessary to make it so perfect. We learned from our mistakes and in the end, everything turned right.

On the other side, there were some challenges we wish we should have tackled during the design process.

One of them is the wind load. Even though the weight on the center creates a balance for the cantilever units, taking a closer look at the wind load and the deflection of the individual units would have made our design more realistic.

The attachment to the bollard was not fully resolved. In the last design week we tried to get into more detail in the connection between the metal pole and the concrete bollard. We made some sketches and got a couple of options but we were not entirely sure about them. A few more days would have been enough to completely solve it

Building Weeks:

One of the most fun and educational parts of the whole studio was the Building Weeks. At first, we had all our drawings ready but we did not have a proper schedule and did not know which tools and techniques are the best fit for us; which made us end up losing a little bit of time in the beginning. Luckily, with the help of Marcel, Nadia, and George we managed it quickly and adapted to tools and materials. Furthermore, we had to revise all the drawings to make them fit the available materials we have, especially the pole we collected (which used to be an air duct).

It was very effective and joyful to use all these power tools and be the engineers behind our design. We mainly used the router and a shaper, which gave our design its unique pinkish appearance. We all were quite excited to see how the mechanism operates so we couldn’t wait but assembled the parts we constructed before taking a photo.

Is it a good idea? Yes!

We believe that our design is proposing a sunshade that can be operated by people of ages and can be located not just in Delft but anywhere having a concrete base, especially on the bollards. It is a good improvement for urban furniture, making security elements feel safer and more useful for the pedestrians and the city by giving an aesthetic look in contrast to the securi bollards. Even legos can get benefit from OSTRA, if they need shade!

Can it be improved? More yes!

Our end product needs more improvement in terms of material selection, bulkiness, number of components, and some further load analysis.

Currently, we have lots of components and materials that can be considered expensive. Our first idea would be to replace the carbon fiber with a more budget-friendly alternative but maintaining the properties of stiffness and lightness needed for that element. Secondly, we would change the material of the joints. It was designed as an aluminum cast element, but after we learned from one of our peers during the final presentations, it would be a better option with magnesium cast. Thus, our design could be stiffer, stronger, and more inexpensive compared to the options we have now.

In the end, it was a special Bucky Lab journey. We enjoyed collaborating with each other as a team at the OSTRA. We not only learn from each other but also from our professors, our colleagues, and everyone else who was there with us. It was great to see so many cool projects being realized.

A very special thanks to Marcel and Nadia who guided us endlessly throughout the process and encouraged us to strive for the better and giving the opportunity of a hands-on project and experiment for turning our sketches into real working models. Also, thank you for reminding us the process is our real journey, mistakes are a key to success, and most importantly to having fun during this very special Bucky Lab journey!

We also had a great group dynamic during these weeks, always asking each other “what can I do further?” or “do you need any help”. We guess we enjoyed our company quite a lot so that we were even spending our lunch times together!

We finalized our modeling weeks by having three different scale models: 1:1 showing the mechanism of the design, 1:2 showing our shading unit, and 1:10 our overall design. The highlight of the process was seeing the smile on our pink dust-covered (thanks to our fins)

Also, we were not quite happy with having a bulky appearance on an already bulky concrete. To overcome this, we already came up with a more aesthetic and lighter idea with the use of uniquely designed diamond framing around a glass pole. However, we could not evaluate the design yet if it would support the structure in terms of strength. Another reflection on our design, which we received from our peers and tutors during the presentation was the various sizes of the shading elements we had, which was not making the individual units modular.

- Team OSTRA

7.2 FUTURE CONSIDERATIONS

In order to change the bulky look of the design due to the pole, we come up with a diamond shaped exoskelet giving a lighter look for the design. However, we did not calculate the technical analysis.

OSTRA has the potential of being installed in mutiple locations. Locations with existing bollards can be identified all across the Netherlands as well as around it. It ctan provide shade to not just human beings but also giant lego blocks.

With Exoskeleton

Before even applying to the Building Technology Master Track, I was most curious and excited about the Bucky Lab course. It lived up to and even exceeded my expectations; it was the perfect introduction to this advanced level of study for me, who had a background more focused on design, far from engineering field.

The transition from design to constructing our ideas, reasoning and understanding a global problem and then focusing on a specific location; how to tackle these problems and all that it entails was incredibly enriching. The course structure also seemed appropriate to me, progressing from the conceptual and individual to the constructive detail and working in a group. The collective stage was the most extensive, since our professional roles will never be isolated, learning how to help each other within the group and even with other groups is essential in professional life. At the end of every session, I always felt that I had learned something new, not only from the professors but also a lot from the group work, especially when we made mistakes. The atmosphere in the studio was never stressful, which encouraged better learning. Bucky Lab day was always expected, a time when we kind of forgot about the other courses and just focused on learning through the discussion sessions with the group. I think that is where everything gains more value after exchanging ideas, besides all our group members came from different places in the world and each one had a different perspective. However, we knew how to find a balance and enjoyed the process. The highlight was undoubtedly the building weeks, having the opportunity to work with power tools and technological tools, such as the shaper, and make reality our own designs was amazing. Definitely long and tiring days but full of learning. But after all, what I appreciate most about the course is how my group mates and I managed to mesh very well academically and personally. We knew how to support and complement each other.

Marco Daniel Aristizábal

A hands-on journey I’ll never forget! I always enjoyed being designer, but there was always something on my mind keep saying “but, how this will get constructued?”. This thought led me ended up being here, at Bucky Lab. had an amazing time with a group of people, mostly coming from architecture background, having passion about learning the technical aspects behind the design.

During each studio session, I learned something not only from our professors or groupmates but also from our colleagues. As the design weekend passes our studio was filled with many cool prototypes. During the elevator pitches, we came up together as having similar ideas but decided on choosing Shashvat’s as having a smart location. Being a part of the OSTRA team, was a great collabration. I have enjoyed their professional and personal company who have a lot of talents. Before that, I have never had the chance to team up with people coming from different countries! Collaborating with them showed me the importance of how different perspectives can lead to better results.

The building weeks were the most exciting two weeks for me. I was impressed by the number of power tools in the construction hall, which I had never worked with before. The two weeks passed quickly, a little rush but mostly fun. I was very satisfied to see three of our models finished on time. At the end of the week, I remember seeing the boys not being able to leave our prototype because it was so great to see it working!

In terms of the design, I wish we had spent more time on the aesthetic part of our design and making it more flexible and unique. We could have optimized further technical calculations to make it stiffer for external forces. However, I think the charm of our prototype is its rotational mechanism. It was very interesting and beneficial for me to learn all these mechanical systems which are hidden in our design. I remember as a group sitting in the studio thinking about “how we can turn this system efficiently”, and in the end we really did!

A special thanks to Marcel and Nadia for reminding us to have fun throughout the process, improving our knowledge every session, being available for the smallest questions, and reminding us that making mistakes can lead to better success. And of course, other special thanks to my teammates who made my Bucky Lab journey more fun. It was fun to collaborate with them! Ece Sel

7.3 INDIVIDUAL REFLECTIONS

After this long period of working on the Bucky Lab project I have a satisfied feeling. In the first few weeks it was hard to find a sunshading solution that could compete with an umbrella on my own. I got stuck a bit and a had lack of motivation because of this.

Bucky lab was one of the courses I was looking forward to in the master’s track of building Technology. The hands-on approach to design was exactly why i applied for this course. I was quite excited with the design brief as it was something that had never been done in my bachelors or my professional practise. The best part of the course was also a perfect amalgamation of engineering and design.

After the elevator pitches I saw what everyone did and what was possible; I looked forward to further developing a design which was not my own. The choice of joining OSTRA made sense because it most resembled my initial design and I really liked the way the bollards were given an extra function.

After the bachelor degree where what you drew did not have any consequences, this was the first time my drawings came to life. This way of actually building something you design makes you think twice of the decisions you make. In the end the prototype has to work in real life, there is no photoshop where you can hide small mistakes or leave out what you do not like. It thaught me to go further into detail than I had done in my previous projects.

The OSTRA team was a very nice group of people who respected each other and listened when someone was suggesting a design proposal. We had some small discussions but we always found an agreement and we never really collided.

In the end I think we have turned Shashvats initial design into a workable shading solution. Although it may not be the cheapest and most simple product, our expectations were met and I had a great time doing so!

Eloy van Kessel

This really helped me develop my design ideology in terms of solving complex assembly problems. “Why, what and how?”, these questions were the fundamental blocks of the Elevator pitch. It was a first-time experience for me where I had to sell an idea to group of students and tutors. To do that, I understood that one must have the confidence in their own product to be able to sell a story. I was fortunate enough that some people actually liked my concept and eventually became my team members for the rest of the course. Working in a very diverse cultural group, with my colleagues coming from different parts of the world was an enriching experience. All of us had some field of expertise that we could capitalise on during the weeks. Eloy was really good at figuring out moving parts of our design. Daniel brought his 8 years of field experience on the table by critical analysis of problems and detailed construction drawings. While Ece brought forth her design skills with softwares such as Rhino and Grasshopper. Guidance was given by both Nadia and Marcel along the way. It was an amazing time whenever we had discussions with the tutors. I personally feel that we as a group could have worked on physical models a bit more to have more iterations of our design coming to life. But I am still satisfied with the scaled models that we made eventually. Building weeks was by far the favourite part of the entire course. The excitement of working with power tools and seeing a prototype coming to life was the reason to get up every morning and cycle all the way to the factory in temperatures below 0o. Finally, caping the course with a presentation and report helps put all the learning together in a cohesive manner. Another drawback that I found in our process was lack of structural design and building physics calculations to make our design even more sound, but one cannot dream to achieve everything in such a short span of time. However, I learned a lot from course about ball bearings, combination of gears, rotating mechanism and finally designing light weight structures. Our respected tutors have been very patient and encouraging with us and were very polite to point out flaws in our design every week. Their constructive criticism made us work together as a group and I can say that we were quite compatible. I have learnt a lot from my fellow teammates and look forward to working together again.

Shashvat Shrotria

REFERENCES

A complete guide to bollards - bollard definition, history, uses, and more. Reliance Foundry Co. Ltd. (2021, June 14). October 15 2022, from https:// www.reliance-foundry.com/bollard/bollard-definition

Atg. (2021, September 20). Bevel Gear vs. Worm Gear: Advantages & Disadvantages. ATG Engineering. Retrieved November 5, 2022, from https://www.atg-engineering.de/en/bevel-gear-worm-gear-advantagesdisadvantages/

Malaga, R. Yter company, Spain. (2022, October)

Marsh, A. (2015). 3D Sun Path [Software]. http://andrewmarsh.com/apps/ staging/sunpath3d.html

Thank you