PART C
C.1 DESIGN CONCEPT LITTER FLOW & CELL CONFIGURATION In my Part B crit it was suggested that I use computational fluid dynamics to explore the configurations of cells in the proposed filtration system. This was a very constructive suggestion as it helped me to approach the development process in a more systematic and evidence-based manner. I used Maya, an Autodesk animation, modelling and simulation software package, to test various cell configurations for their ability to retain particles. In Maya it is possible to set up particle emitters, attractors and colliders in a way that you can see how particles interact with a static obstacles when acted on by a force. To test my iterations I set up a section of the creek with the design intervention midway along the length. Particle emitters were installed upstream and Newton forces were placed downstream (one near the exit points of the system to imitate the lateral suction, another further along to represent the pull downstream). The system was designated as a passive particle collider, meaning that particles would have to interact with it as a solid object. I opted to go with this method because I felt that the particle (litter) behaviour was my key concern. I ran a simulation in Maya after creating each iteration and incorporated the lessons from that version into the subsequent proposal. I documented this process in the following pages. The images on top are from my Maya trials; the images below are from Rhino and have been included for clarity. The colourful dots are the particles released into the simulation. The aim was to achieve the maximum number of particles inside the system and a minimum outside. All simulations were run under the same conditions. I acknowledge that there is a flaw in the logic of this method. In theory, the most effective system would be the one that blocked off the entire stream, as it would allow zero particles to pass through. However, damming the stream is not the objective and would be prohibitive to the movement of any aquatic fauna. I chose to stop projecting the intervention out into the stream when I felt that the vast majority of particles were being retained by system. The particles typically gathered around the forces (designated by the little black asterisk shapes) in the screen shots, so the amount of particles you see in the screen shots is more or less the total amount of particles operating in the simulation. Therefore, when there are no particles accruing near the forces this is because they are being successfully retained by the simulation. As such, there is a point when it is no more effective to project further outwards and therefore it is unnecessary to block off the stream. 58
PROJECT PROPOSAL
ITERATION 1. seed that produced a lot of large faces oriented upstream. It is obviously not particularly effective as indicated by the lack of particles inside and vice versa. Lots of particles were bouncing off the closed cell at the periphery, which was a wasted opportunity. The upper exit point is also at the end of an effectively straight line between 4 cells. This is not establishing a barrier to the particles’ release.
ITERATION 2.
ITERATION 3.
Opening that outer cell and relocating an exit point did improve retention, but there were still a lot of particles bypassing the whole system. This iteration did not project far enough out into the Creek.
An intervention that projected further into the creek did extract more particles, but it’s obvious that there are a lot of inactive betrayal of the attempted environmental conscientiousness of the project and should be avoided where possible.
PROJECT PROPOSAL
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ITERATION 4. Here I tried to mimic the reach of the previous iteration but with larger, fewer cells to minimise material wastage. As indicated by the cluster at the bottom left of the image, this was not entirely successful. There was a relatively direct route between 3 cells that meant particles were spilling out an exit point.
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PROJECT PROPOSAL
ITERATION 5. In this iteration I tried to install further obstacles (by creating a Voronoi diagram within a Voronoi cell selecting sub-cells) to direct the flow of the particles into the system. This was only partially effective because particles were spilling both towards and away from the design. I evidently chose the wrong geometry for the obstacles.
ITERATION 6. I changed both the obstacles and the seed of the Voronoi used at the periphery downstream projected out further than the cells upstream. I thought I could use this as an opportunity for an additional entry, but didn’t create the apertures optimally. Also, there were too many openings aligned again.
ITERATION 7. In this iteration I inserted a couple more obstacles to control the flow inside and outside the intervention. One obstacle channels the flow of particles more precisely into the system and the other blocks one of the exit points.
PROJECT PROPOSAL
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FINAL CONFIGURATION
ITERATION 8.
obstacles to stop the direct flow of litter out of the system.
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PROJECT PROPOSAL
I attempted to verify my results from the Maya simulation RealFlow was recommended because it enables users to combine solvers so that you can, for example, accurately simulation. I struck a snag insofar as geometry can only be It’s possible to get a plug-in for some Autodesk products to RealFlow, you have to buy a license to access their plug-ins. Unfortunately, I’m not in a position to do this at the moment. The image above shows in more detail the final iteration from the Maya simulations. PROJECT PROPOSAL
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UPDATED FILTER
1. DETERMINE FILTRATION SYSTEM FOOTPRINT Create rectangle generously bounding site; set rectangle in Grasshopper. Populate rectangle with points and apply Voronoi. Apply seed arrangement Voronoi cells. Set curve that approximates river bank. Use List Item to select cells within site boundary. Find intersection of selected Voronoi cells and curve.
COUNT
VORONOI
LIST ITEM
SEED
INDEX
COUNT
BOUNDING BOX
LIST ITEMS
REC
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Set bounding box around cells determined to need obstacles. Populate cell with points and apply Voronoi. Vary Voronoi parameters until desired size and geometry of sub-cells has been reached.
BREP INTERSECTION
CURVE
POPULATE GEOMETRY
2. SUBDIVIDE VORONOI CELLS
INDEX
CRITERIA DESIGN
3. DETER OBSTA FOOTP
Use List Item to pick c particle flow favou Intersection if sub-ce
SEED
IND
VORONOI
LIST I
POPULATE GEOMETRY
BR INTERSE
DESIGN PROCESS
. RMINE ACLE PRINT
cell that will redirect urably. Use Brep ell is to be cropped.
4. EXTRUDE FRAME & OBSTACLES
5. MAKE FILTER CELL BASES & LIDS
Extrude the products of the previous step along the z-axis to create the internal and external obstacles.
Move offset wall boundary along the z-axis to
internally with a negative value to establish the
the frame. Offset this perimeter to create the inner
and cap both. Solid trim the capped footprint extrusion against the offset walls to create the frame.
step to separate the cells into lids and bases.
Z AXIS
DEX
ITEMS
REP ECTION
EXTRUDE
CAP
OFFSET
MOVE
Z AXIS EXTRUDE
Z AXIS SOLID TRIM
CAP
OFFSET SPLIT
EXTRUDE
CAP
Z AXIS
CRITERIA DESIGN
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RI
ER
M
D A O R G R BE L E D HEI
K
EE
CR N 10M
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PROJECT PROPOSAL
SITE JUSTIFICATION In my crit it was suggested that the location was undesirable or inappropriate for recreational use on the grounds that it would just be too unpleasant for people to want to pause and hang around. Whilst I agree that at present the site is not in a great condition, I’d suggest that the site is intriguing and does have inherent beauty. The bridge, both aesthetically and functionally, was an important reason for choosing the alone. Standing under it is one of the only points in this stretch of trail where site users get an uninterrupted view along the water because of the density of the trees, which is also an appealing aspect of the site. The way the light refracts off the water casts delicate, dynamic patterns on the barrel of the bridge that are quite captivating and make the space interesting to observe. The variable angle of the sun in the sky as the seasons change also mean that the bridge provides shade in the summer but its underside is well let in winter, which is ideal in terms of thermal comfort needs.
FIG.30 (LEFT): SITE PLAN. FIG. 31 (RIGHT): LIGHT PLAYING ON UNDERSIDE OF BRIDGE. FIG.32 (BELOW): VIEW ALONG RIVER FROM UNDERNEATH BRIDGE.
PROJECT PROPOSAL
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APPLICABILITY BEYOND MY CHOSEN SITE where Heidelberg Road crosses Merri Creek, the principle behind the system is much more broadly applicable. throughout urban environments and could be implemented systematically along others such as the Yarra River and the Maribyrnong River. Intersections of waterways and roadways as well as stormwater drains are key sites where of pollution here is much higher. Bends in waterways are also key areas for consideration. Water must slow down as it follows bends, which means there is naturally a process of aggradation of sediment and litter at these points. The aerial view of Melbourne in Figure X demonstrates where diagrams overlain on the photo are representative only of a proposed location, they do not represent a proposed
FIG.33 (IMMEDIATE RIGHT): MAP OF STUDLEY PARK REGION WITH SUGGESTIONS OF WHERE ADDITIONAL FILTER SYSTEMS COULD GO (NOT TO SCALE). FIG. 34: (FAR RIGHT): DEMONSTRATION OF FILTRATION SYSTEM APPICABILITY TO ANOTHER ENVIRONMENT. 68
PROJECT PROPOSAL
PROJECT PROPOSAL
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C.2 TECTONIC ELEMENTS & PROTOTYPE FABRICATION, CONSTRUCTION DETAIL & DETAIL MODEL
CELL LIDS Model fabrication: I stacked layers of pasteboard cut to the shape of the lids in plan, then sanded the edges to make the lamination less visible. Real world Fabrication: The cells and sieves would be constructed from extruded recycled plastic if the intervention was to be constructed in real life. Because of the size of the units, individual planes would likely have to be sheet/film extruded and then thermoformed together. SIEVES & BRISTLES Model Fabrication: The sieves were constructed by hand cutting and scoring pasteboard. I opted for hand scoring here because I wanted to use as few individual pieces as possible because increasing the number of joints increases the weakness of the structure. I cut and scored one piece that I could fold around on itself. The bristles are represented with florist wire, which is wedged through the sieve floor and sewn to the pasteboard beneath it. Real world Fabrication: In real life, it would be preferable to use something less rigid and more textured for the bristles that could move with the water and that would snag against litter in the system. CELL BASES Model Fabrication: I hand cut the pasteboard for the cell bases so I could mitre the edges, but I should have used the same technique I used for the frame. I couldn’t cut the angles with great enough accuracy so the cells looked messy when assembled. I tried to cover this up with a single horizontal layer on top. On reflection, it was illogical to do it like this because the bases are embedded in the frame so the lamination would hardly have been visible anyway. FRAME Model Fabrication: I made the frame using horizontal layers of lasercut MDF. I opted for horizontal layers because if I were to use vertical strips the edges would need to be cut at an angle to fit together correctly. This was not possible given the production process I was using and had proved unreliable in my attempts at the cell bases. Assembling the frame in lasercut layers allowed me a greater degree of precision, but the lamination visible at the sides is not representative of the system’s intended appearance. Real world Fabrication: If the intervention were to be made in the real world, the frame would need to be made from vertically aligned pieces instead of horizontal ones. The frame extends into the foundations of the creek to act as a footing system, and without the vertical continuity the footing system would be ineffective. The frame would be constructed of WPC (wood plastic composite), which is more durable than conventional timber when exposed to water and uses recycled timber and plastic products.
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PROJECT PROPOSAL
FIG.35: UNDERSIDE OF LID IN DETAIL MODEL.
FIG.36: SIEVE BLOCKS CONSTRUCTION DETAIL.
FIG.37: DETAIL MODEL OF SEVERAL CELLS COMPRISING THE SYSTEM.
PROJECT PROPOSAL
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CONSTRUCTION DETAIL & USER INTERACTION active participation by community groups to maintain. As such, I tried to design the system in a way that could easily be navigated by a couple of people. Sieves sit permanently in the cells and are lifted upwards during cleaning, combing out rubbish that has collected in the cells. This prevents users from having to rummage through the water in the cell and pick pieces of litter out from between the bristles. There are small subtractions from the corners of the sieve frames in which blocks can be placed to keep the sieves suspended whilst they are being emptied. Through it’s peculiarity in the landscape, the intervention will naturally attract curiosity. This is an opportunity to bring to the attention of site users information about the was based and directories on how to become involved with the maintenance. On the lids of the cells will be QR codes which will lead to a website providing information on these topics. I thought a website would be preferable to a static sign because it can more easily be kept up-to-date.
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PROJECT PROPOSAL
FIG.38 (ABOVE, TOP): SEQUENCE SHOWING OPERATION OF SIEVES. FIG. 39: SECTION THROUGH BRIDGE..
PROJECT PROPOSAL
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C.3 FINAL MODEL SITE MODEL & DETAIL MODEL
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PROJECT PROPOSAL
FIG.39 (LEFT): SITE MODEL IN PLAN, BRIDGE REMOVED. FIG.40 (RIGHT, ABOVE): DETAIL MODEL, CLOSED AND OPEN. FIG.41 (RIGHT, BELOW): SITE MODEL IN PERSPECTIVE. FIG.42 (NEXT PAGE): VIEW LOOKING NORTH UNDER THE BRIDGE. PROJECT PROPOSAL
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PROJECT PROPOSAL
PROJECT PROPOSAL
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C.4 ADDITIONAL WORK
CREEK WATER LEVEL & FILTRATION CELL APERTURES advisable to narrow the openings vertically as I originally intended because that would mean there are times when water would be stagnant in the system as creak levels change. As such, the apertures could only be made smaller horizontally. Melbourne Water record information on rainfall and water levels for various waterways in Melbourne. Unfortunately, but there was one approximately one kilometre upstream at a comparable site in Northcote. I used the information to approximate what proportion of time the water level of the creak would fall within the aperture dimensions of the system.
Present dimensions only allow for water entry 79.4% of the pollution is highest and, theoretically, it is most important that the system is operating.
platform has to be elevated. It was important to the design that the platform was a level between the pedestrian path and the water because it makes the Creek more immediate and encourages greater engagement, but if the thrust of my design is functional it didn’t make sense to compromise that functionality for some symbolic design intention.
MEAN LEVEL OF MERRI CREEK 2010 - 20151
Day of the Year Band indicating values that would fall within opening dimensions ranging from 0.2m - 0.5m above creek level
Band indicating values that would fall within opening dimensions ranging from 0.1m - 0.9m above creek level 78
PROJECT PROPOSAL
1 MELBOURNE WATER, ‘RAINFALL AND RIVER LEVEL: NORTHCOTE’ (2015) < HTTP://WWW.MELBOURNEWATER.COM.AU/WATERDATA/ RAINFALLANDRIVERLEVELDATA/PAGES/RAINFALL-AND-RIVER-LEVELNEW.ASPX> [ACCESSED 23 MAY 2015].
79.4% the percentage of days with creek water levels that lie within the initial proposed filtration cell opening dimensions
11.2% the percentage of days with water levels that exceed the maximum height of the filtration cell openings
9.4% the percentage of days with water levels that do not meet the minimum height of the filtration cell openings
0.5M Max. Entry 0.2M Min. Entry 0.0M Creek Bed
PROJECT PROPOSAL
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CHANGING APERTURE DIMENSIONS TO INCREASE FUNCTIONALITY
FIG.43 (ABOVE): NORTH ELEVATION. FIG. 44 (RIGHT): DIAMGRAM SHOWING FINAL HEIGHTS OF CELLS, FRAME AND APERTURES.
After assessing the functionality of my initial system dimensions against the water levels of the creek, it became apparent that it was necessary to increase the dimensions of the apertures. By increasing the size of the openings from 0.3m to 0.8m, the percentage of time for which the mean height of the creek sits within the system apertures increases from 79.4% to 95.7%. This is achieved without greatly increasing the height of the frame, which still allows for a difference in levels between the pedestrian path and
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PROJECT PROPOSAL
The varying height of the lids is intended to accommodate people using the site as chairs and tables. There are three 0.25m taller than the frame; another is 0.5m taller than the frame. Each cell is surrounded by 0.2m of frame, so where two cells abut one another there would be a gap of 0.4m. This distance is intended to be a comfortable distance to walk between but also a safe distance to bridge if stepping from lid to lid.
95.7% the percentage of days with creek water levels that lie within the revised filtration cell opening dimensions
0.25M
0.5M
1M
0.8M
PROJECT PROPOSAL
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C.4 LEARNING OBJECTIVES & OUTCOMES Whilst I think my project was very simple relative to what of the learning objectives.
the age of optioneering. I chose a computational design tool appropriate to the function of my design vision (Voronoi diagram – biomimetic in its own way, but that also geometrically made sense to employ because it easily builds indirect pathways), used CAD tools to develop various my proposal based on the outcomes of these simulations. Iterations were produced by altering key parameter inputs for the Voronoi diagram in grasshopper and by selecting from these the proposals that possessed qualities shown to be most effective through my Maya simulations.
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PROJECT PROPOSAL
Granted I was starting from a very low base, but I do feel this subject has really forced me to extend myself and my technical abilities. I’ve been forced to explore various digital design tools, most notably Rhino and grasshopper, and have
The analytical diagramming component of this subject has been of particular interest to me. Design is fundamentally about communication, and the best idea in the world won’t be convincing if it is not conveyed in an approachable and persuasive manner. I believe practicing analytical diagramming in this subject has improved my ability to communicate my ideas by forcing me to break things down into their salient points and to explain those points in a logical sequence. I think this relates closely to the impact that Grasshopper itself as a visual programming language has had on my thought process. At the beginning of this
semester Grasshopper was visually so confronting and incomprehensible to me, but I think it has forced me to understand simple objects (eg. a circle) in more complex terms (eg. circle as a combination of plane of alignment, origin point, radius etc). It has helped me to understand to a greater extent the relationships between components of a whole. As a result of attempting to fabricate part of my models by of digital fabrication is unparalleled by that of manual models. However, in Part A it was so forcefully emphasised that part of digital fabricationâ&#x20AC;&#x2122;s lure is the speed it brings to design and the potential it has to increase the pace of the design process. This was not my experience. Obviously if I fabrication unit things would be different. But we had to book an appointment a week in advance at the Fab Lab to get a
consultation for 3D printing, and laser cutting took 4 days when I was submitting my job. I made part by hand because it was quicker than digital fabrication. I would argue that digital fabrication at university just changes the loading of the design process to make the beginning much more top heavy because it requires so much more preparation. I still feel limited in terms of what I can produce using computational techniques. But maybe part of the lesson is that parametric design is not appropriate for every situation. Going forward, I feel greatly advantaged by being exposed to the computational design techniques in Studio Air. It has expanded my imagination, my ability to engage critically with the built environment and my faculty for design conceptualisation, not to mention provided me with real technical skills.
PROJECT PROPOSAL
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C.5 REFERENCE LIST TEXT SOURCES Melbourne Water, ‘Rainfall and River Level: Northcote’ (2015) < http://www.melbournewater.com.au/waterdata/ rainfallandriverleveldata/Pages/Rainfall-and-river-level-new.aspx> [accessed 23 may 2015].
IMAGE SOURCES FIGURE 33: Aerial photograph of Melbourne, retrieved from <http://services.land.vic.gov.au/maps/mpmo.jsp> [accessed 15 June 2015].
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CONCEPTUALISATION