Body Parametrics

Date Posted: 02.11.2020

By Ethan Davis

Anthropometry, the study of the human body’s shape and proportion, can be recognized as one of architecture’s earliest tropes. Expanding on this tradition, a recent Mithun R+D effort entitled “Digital Anthropometry” investigates how the body can be embedded within contemporary design utilizing emergent digital fabrication tools.

Using a combination of computer scripting, 3D printing and five-axis CNC fabrication, our design team researched how to effectively model complex anthropomorphic shapes and directly cast them into concrete forms. The team applied this research to design and fabricate a 24-foot-long concrete bench commissioned by the recently opened Louisiana Children’s Museum (LCM).

Inspired by Louisiana Landscapes and Families
The design concept for the bench is a smooth concrete ‘landform’ which subtly grows out of the earth, retaining two grass hummocks for additional seating and play. The sinuous, s-shaped form of the bench offers families multiple options for active exploration of the mounds and museum’s south lawn, or quiet contemplation with views to the neighboring lagoon. The cooling shade of a mature live oak tree provides refuge from the hot sun. The form is intended to support intergenerational connection and play with comfortable elder seating in the line of sight to areas for young children’s active play and exploration upon the grassy mound or within the seating arc.

Inspired by LCM’s goal to accommodate all ages, the profile of the bench is defined by blending physical measurements of youths, adults and elders—generating a final form which ergonomically supports a spectrum of age and size. The bench’s form playfully shifts and morphs along its length, engaging the user to find which location accommodates them best.

Applying Emergent Digital Tools
Computer scripting was used significantly in the production of the LCM bench. In recent years, computer scripting has become integral into the architectural design process to both automate tasks and rapidly generate forms through parametric modeling. For this project, the R+D team used scripting to quickly test and ‘digitally sculpt’ complex doubly-curved surfaces, often unviably cumbersome for traditional design tools. The team used human body dimensional data to drive the form of the bench profile, including the backrest height, seat height, and seat width. The angle of the seat and backrest reference ergonomic guidelines for both younger and older users.

Unlike parametric scripts solely steered through numerical controls—often rigidly constrained and difficult to use—the team focused on creating a script which allowed for maximum flexibility. The bench form was guided by both numerical controls along with a series of more flexible control point parameters, allowing for a more artistic crafting of the model’s form. Using both control points in tandem with numeric parameters allowed for a much more fluid control of the model and created a more intuitive design process. Similar to the way a mechanical pencil will render a different design than a paintbrush, the way we write scripts is directly reflected in the product.

After a desired form was reached, physics engines were used to simulate rainwater drainage and refine the slope of the bench to minimize puddling. Additionally, AR tools and 3D printing were used to quickly visualize and test prototypes at varying scales. The bench design reflects Mithun’s explorative design culture, which employs a wide range of digital and analog tools, and deployment strategies in order to translate ideas into built form, for a wide variety of scales and geometries.

Fabrication and Installation
The Mithun R+D team worked closely with Tectura design in Wausau, Wisconsin, to fabricate the bench. The team used the 3D geometry generated from the script to fabricate the bench in three eight-foot sections, each weighing 800-1200 lbs. Each individual section was cast in laminated foam forms carved from a five-axis CNC. A quote from a past LCM board patron was cast in the backrest using milled polyurethane letters, glued directly to the inside of the foam form.

The cast-concrete sections were shipped to New Orleans, where they were set on a six-inch cast-in-place foundation slab. Earthwork was conducted after the pieces were placed, and the bench shape was molded and integrated into the surrounding grades. After the final design was approved, fabrication, shipping and installation took a total of 14 days.

Inspiring Generations
Now complete, the Nancy Marsiglia Memorial welcomes families to the museum and inspire generations with her inscribed words: “I want my grandchildren growing up to respect others, the environment, but mostly themselves. They hopefully will be caring, loving people who know that their responsibilities are much greater than just to themselves but to the community at large and globally.”