Hands-on Prototyping for BUILDing Forward

Read about the unique opportunity for geometry analysis, fabrication, and the resulting gallery installation as initially reported on the Tocci Blog...

Image Credit: Jamie Farrell

On July 27th, an opening reception was held for Autodesk’s BUILDing Forward exhibit at the Boston Society of Architects. This exhibit celebrates digital craft in the greater Boston community and highlights the research projects made possible by the Autodesk BUILDSpace — a state-of-the-art research and development facility in the Design Center.

Tocci partnered with Sasaki Associates to research and develop a prototype called WinterLight, a proposal for a temporary winter pavilion for the Rose Kennedy Greenway. Currently in the early design phase, WinterLight is a warming hut designed to encourage activation of the city’s public realm during the winter months. The structure is a semi-dome with strategic openings in customized masonry blocks, designed to shield visitors from winter winds while they enjoy the warmth of an interior fire pit. The final location of the pavilion will be located in Boston: the site is to be determined.

Image Credit: Lucca Townsend, Sasaki Associates

This project required extensive computational design from Sasaki staff to strike a balance between desired aesthetic and regularity of the blocks. Tocci’s role was to assist with geometry analysis and support the design process through construction feasibility studies. With each new design iteration, we utilized Dynamo Studio to extract total pavilion dimensions, overall block quantities, block sizes, repeatable types, total volume, total weight, and other metrics.

Image Credit: Lucca Townsend, Sasaki Associates

The BUILDing Forward exhibit provided the perfect opportunity to experiment with fabrication methods and materials for producing the unique geometry of the blocks. Sasaki chose a section of nine blocks comprised of five unique types from the overall pavilion to demonstrate scale and geometric variation. They first generated a digital model of the composition, and then processed the individual shapes into toolpaths for cutting profiles from Medium Density Fiberboard (MDF) using a Computer Numeric Control (CNC) three-axis router. They continued to cut an ingenious system of holes into the MDF sheets, lining up each piece using threaded rod. This created a negative form of each block shape for pouring concrete. Each concrete form also incorporated removable sections and a hole at the top for concrete. At this time, they sanded and coated the interior surfaces of the forms with an epoxy sealer to facilitate the release of concrete.

To prep for pouring, we disassembled the forms to coat the interior surfaces with form release. They were then reassembled on the threaded rod guides and tightened using nuts and washers.

We blended Portland cement and sand silica to create a concrete mixture that could support the compressed weight of the stacked blocks and maintain a smooth, gallery-quality finish. As each five-gallon-bucketful of concrete was poured through the top, a team tapped the sides of the forms, agitating the mixture and forcing trapped air bubbles to the surface.

Image Credit: Christine Dunn, Sasaki Associates

At times, the form release did not properly work, forcing us to pry the blocks from their forms.

Rotating shifts of the Sasaki-Tocci team spent a week to producing the prototype, as each block required 24 hours to cure. With one last round of chiseling and sanding, all nine blocks were ready for their BSA Space debut.

The opening reception was well attended. It was inspiring to see so many creative projects coming out of the BUILDSpace and local AEC community. BUILDing Forward will be on display at the BSA until October 5th, 2017 if you would like to see our work and all the other excellent projects.

Stay tuned for more as the WinterLight project evolves into a full-scale realization.

Check out this Sasaki blog post about the BUILDing Forward event for even more information.

Parametric Nameplate

In an effort to become better acquainted with geometry creation in Dynamo, I created a parametric nameplate. The design concept was a cluster of “randomly” sized squares to give the appearance of a pixelated brick.

To start, a solid array of points was generated.

To create the illusion of “randomness”, points were removed at random from the array using list management and the List.RemoveItemsAtIndex node. Solid cuboids of varying size were then instantiated at the remaining points.

Lastly, 3D text solids were generated and placed centered at the front of the cluster of randomized squares. By using a boolean difference function, the text was subtracted from all of the intersecting cuboids. With the boolean union all function, the resulting shapes were all conjoined to form a unified solid.

In preparation for 3D printing, I exported the final solid as an .obj file to Rhino. Tools such as _Check and MeshRepair in Rhino are excellent for quality control and making sure that an object is “watertight” - no holes or manifold edges - so that it will successfully print.

Whether sculptural objects or architectural forms, many designs contain cantilevered elements that are difficult to print with additive technologies such as a MakerBot. In this model, the variation in stacked cuboids created several locations where cantilevers occur. Autodesk makes an excellent application called Meshmixer that can help with this problem. Meshmixer offers the ability to create, modify, and analyze the fidelity of objects for 3D printing, however one of the most useful features is advanced supports. The model is evaluated and automatic, branch-like structures are generated to meet the underside of cantilevered objects.

The supports allow for flawless printing and easily break away from the model after the print is complete to reveal perfect cantilevers.

Dynamo for Digital Fabrication

CUSTOM MAGAZINE RACK
Recently I set out to create a custom magazine rack in an effort to cover up an unsightly electrical panel in the living room of my apartment. My first attempt at modeling design ideas in SketchUp proved to be very time consuming because every slight adjustment to the design required re-modeling entire portions of the geometry. Eventually I came up with the idea of building a parametric model using Dynamo that could not only explore many iterations with minimal adjustments but also could simulate materials and assembly strategies.

To begin, I created a solid form in Dynamo that reflected one of the designs I had refined during earlier studies in SketchUp. I then generated two additional solids and applied a boolean difference to carve out a mail slot on the top and a slot for magazines on the front. I set the magazine slot at an angle so that magazines could easily be inserted and the top portion of the covers would remain exposed to display their titles.

Another key consideration was how the rack would mount. I ended up settling on a 12” metal picture rail with a 1/2” front lip that could be inserted into a slot in the back of the rack and attached to the wall. To incorporate the slot, I created another solid for the void space that the picture rail would require and again used a boolean difference function to subtract from the full design.

For materiality, I just so happened to have an excess supply of 1/8” thick Baltic Birch plywood lying around so I decided the form would be nicely defined by evenly spaced vertical wood fins. To simulate the wood elements in Dynamo, I created planes set perpendicular to the wall mounting surface, copied each plane 1/8” to imitate the thickness of the material, and introduced a parameter for spacing between the pieces of wood to evaluate visual density. The planes were then used to intersect the solid geometry and leave behind the isolated slices of the original form as a representation of the wood. The parametric constraints facilitated quick adjustments and counts in the Dynamo definition ensured an economy of materials by balancing the desired look with a reasonable amount of wood used.

The next step was to add cross-bracing for structural stability. End cap pieces were added to the top and bottom as well as a support piece in the center of the rack tucked alongside the picture rail. To guarantee precise and equal spacing of all the vertical baffles, intersecting geometry was subtracted and tolerances were added to interlock all the pieces together.

After all the geometry was finalized, each piece was rotated and flattened onto the same plane for export to SVG. I opened the SVG file in Adobe Illustrator and used the vector lines to laser cut all the individual components out of corrugated cardboard to construct a mock-up. The SVG file format can also be exported to a DWG or DXF from Illustrator for use in AutoCAD.

The mock-up revealed that some of the tolerances were too loose, causing the magazine rack to easily lean from side-to-side as a result of inadequate interlocking of the cross-bracing. The advantage of building a parametric model in Dynamo is that I was able to reduce the tolerances of all geometry in the model ever-so-slightly for a perfectly snug fit.

The final result was a magazine rack that serves as both functional and sculptural. This was an excellent learning opportunity for digital fabrication and most importantly provided yet another purpose for using Dynamo.

Autodesk University 2014

Autodesk University
AU2014 Summary
December 2-4
Mandalay Bay, Las Vegas

Fusion 360 Digital Fabrication Workflows:

This course highlighted several features of Autodesk Fusion 360, a program that facilitates easy manipulation of 3D geometry otherwise difficult to achieve in Revit. After exporting a conceptual mass family from Revit to Fusion 360, an undulating wall form was created that could then be imported back into Revit, populated with curtain wall using adaptive components and rendered in a perspective street view with Google Maps background. That same form was imported into a program called Meshmixer that provides advanced options for preparing an STL file for 3D printing and allows you to apply custom supports. Altogether, the integrated workflow across several software platforms was relatively seamless and the course exhibited proof that very complex and customized geometry to be created in Revit for any project type.

Building a Good Foundation with Revit Templates:

Members of the architecture, engineering, construction and manufacturing industries gathered for this round table discussion about best practices for starting a project in Revit. Two methods were compared, the use of a Template File and Default Project. At Shepley Bulfinch, we use a template file at the outset of every project that contains a minimum amount of views, families and general standards to provide a good starting point. A default project has the advantage of carrying much more initial information including pre-placed families and objects but requires a significant time investment to keep the content current. Overall, the common sentiment in the room was that template files are easiest to maintain and offer the most versatility for any project type. Additionally, it is preferable not to “front load” Revit models and start out with unnecessary file size when one of the biggest challenges among all projects is keeping the model as small and responsive as possible.

Energy Analysis for Revit:

Are you familiar with the native energy analysis tool in Revit (hint: it’s under the Analysis tab on the ribbon)? This tool has the potential to be very helpful for early feedback to help drive the design. The task can be farmed out to the cloud for faster processing and to post reports for multiple options. For more in-depth analysis, the Revit model can also be exported to GBSxml format and opened in Green Building Studio, a cloud-based energy simulation platform. Relatively specific configurations are required within a model for the analysis to run successfully and one of the predominant takeaways of the course was the emphasis on modeling with energy analysis outcome in mind from the start of the project.

Challenges of LEAN Design and Computational Analysis:

This very engaging roundtable discussion examined the emerging role of computational analysis and generative design to help make more efficient design decisions. The keynote address at the beginning of the conference featured the use of "machine learning algorithms" where information and constraints are entered into a computer and simulations are run to determine an optimal design outcome. To start this session, we identified wastes and ineffective behaviors within each profession and in the collaboration process between. After a predictable round of architect-bashing, the question was proposed: "Does computation and simulation allow us to come to confident solutions earlier in the design process and reduce waste?" If existing condition information, user requirements, code constraints and many of the other variables that influence the design process can be programmed to generate permutations, is this a promising direction for the future of the profession? The group came to the conclusion that computational analysis and simulation will never be reliable enough to deliver a comprehensive design solution but may be helpful in providing direction at challenging moments in the process.

Practical Uses For Dynamo Within Revit:

Dynamo is a visual programming environment that allows you to make custom changes within Revit and extract information otherwise unattainable with the native program features. The program utilizes a user-friendly graphic interface to make adjustments within the Revit API (the "back end" which contains all the building blocks for how the program functions). This course demonstrated many entry-level uses for Dynamo including:

• quickly making changes to all instances of a family type in a model (example: adjusting the offset height of all columns at once)
• advanced family geometry (example: controlling profile order to create cantilevered and wrapped swept blends)
• wrapping structure along curved surfaces
• generating separate finish floor on top of slab automatically from room boundaries

Utilizing Revit Models for Architectural Visualization:

This course covered work flow and best practices for exporting a Revit model to the Unity 3D, a game engine that enables real-time visualization and walk-throughs. The first step is preparing the Revit model for export by cropping down only what you need with a section box and turning off unecessary categories in Visibility Graphics. Export the model to FBX and import it to 3DS Max where materials, cameras and lights are applied. Lastly the model is imported into Unity where perspectives, walk-throughs and animations can be utilized. In summary, Unity 3D provides a compelling presentation piece that may appeal to some clients but it is important to consider the time investment that goes into the preparation process.

Dynamic Energy Modeling:

An energy and environmental analysis consultant presented a multitude of methods for assessing daylighting, wind, weather, energy consumption and other performance characteristics of a design. Specific tools covered included eQUEST, Green Building Studio, Autodesk360 Lighting Analysis, raytracing and raycasting, Rushforth Tools Library, Autodesk Ecotect and more. Although these programs were generally too advanced for the level of in-house analysis we use at Shepley Bulfinch, I enjoyed learning about numerous ways information can be extracted from Revit and used to help inform the architectural design process.

Revit + Dynamo = The Building Calculator:

Beyond parametric modeling and making tweaks within Revit, Dynamo can be used to extract much of the information stored within a model. By using an "export to excel" function, areas, quantities, dimensions, room lists and so much more can be exported and analyzed with the powerful tools Excel has to offer. Schedules can be created, complex building calculations can be scripted and automatically updated upon every change within the model, or checks and balances for code and zoning can be integrated to produce reports. Items can then be adjusted, renamed or resized to push back into Revit from Excel and make direct changes to the model. Dynamo provides a giant step forward in the pursuit of harvesting the full potential of BIM.

The Great Dynamo Dig: Mine Your Revit Model:

With all this excitement surrounding Dynamo, did you know there is also a SQL export function? This allows for the creation of a much more comprehensive database that can be thoroughly organized using database management software and mined for analytics and appealing visual graphics in Tableau.