This project was inspired by Op Art, a twentieth century art movement and style in which artists sought to create an impression of movement on an image surface by means of an optical illusion. Passive elements consisting of composite laminates were produced with the goal of creating lightweight, semi-rigid, and nearly transparent pieces. The incorporation of active materials comprised a unique aspect of this project: the investigation of surface movement through controlled and repeatable deformation of the composite structure using SMA wiring technology. The integration of composite materials with SMA wiring and Arduino.
In the 1960’s art world, some critics faulted Op Art’s persistent involvement with optical illusion at a time when “the flatness of the picture plane” was the mantra on either side of the Color Field–Minimalist aisle. Op Art works are abstract, with many of the better-known pieces made only in black and white. When the viewer looks at them, he or she has the impression of movement, hidden images, and flashing and vibrating patterns.
The basic pursuit of this research project was to incorporate both perceptual movement and real movement in architecture, which is an uncharted field. As a line diagram, this project works in Deleuzean terms, basically isolating the figure to break with representation and tie fact and matter. In The Logic of Sensation, Deleuze discusses this isolation of a figure to its spatial context and how it helps overcome representation. Deleuze applies the same kind of thinking that he intends the figure to disrupt by juxtaposing figural and abstract representation . An important aspect of this current project—and one that is characteristic of my research—was the combination of two different sensibilities: the parametric geometric field and the moving flowers and motion-scaled panels, all articulated into a particular atmosphere.
In this project, when we discuss representation, the question of depth becomes critical; it is important to bring the notion of the Gestalt, conceived as a figure against a background. We think of Gestalt as precisely the interplay between the figure and the ground, and Pop-Op treats both as the same by juxtaposing planes of representation and literally producing both depth and figure. Any variation in the figure itself will cause reciprocal topological variations in the underlying field.
According to Henry Somers-Hall, “Husserl’s error is to fail to realize that the ground itself is a part of the figure. The ground and figure are different in kind, but also, as is shown by the possibility of infinite regress, infinite reversibility prevents their reduction to a homogenous plane” . This understanding of a figure emerging from the ground is what we will refer to as 2½ dimension. First, it must be understood that the number 2½ is not to be taken literally. It has nothing to do with actual half dimensions or with fractals. Rather, this number negotiates the concept that in reality, we tend to mix figure and ground: “We do not actually see all three dimensions surrounding us. Rather, we construct the three dimensions in our mind and project them onto the objects surrounding us.
The final design for the Pop-Op was crafted through a parametric design process. First to begin the digital design of the overall surface, we prepared an a sample image in illustrator Adobe Illustrator that incorporated the preliminary criteria for a 2½-D drawing with showing all the desired Op Art effects as and well as the desired color palette. The sample image was highly saturated in order to produce a greater variation of hues in the final image. A hand-derived pattern was overlaid in red onto the sample image. The scripting software would later use this pattern as a map for the final image. The generative algorithm software Grasshopper was chosen to carry out the parameterization procedure. The process began with the script evaluating the sample image and then interpreting that image through a series of algorithmic steps
The Pop-Op design called for the fabrication of three distinct composite component groups: 28 “panels”, 9 “flowers”, and a large background element. As shown in Figures 7 and 8, the panels are small, roughly rectangular pieces that are actuated with SMA springs. When no actuation is occurring, the panels are flush with the wall surface. During actuation, the SMA springs pull them away from the viewer. The aptly-named flower components are cut into floral patterns as demonstrated in Figure 8. The flowers are actuated by SMA wire running along their surface. When actuated, these flowers bend toward the viewer. The immobile background panel covers the bulk of the Pop-Op surface and complements the morphing panel and flower elements. The material selection and fabrication processes had to take into account the morphing nature of the flowers and panels in addition to the typical design and structural constraints.
The fabrication research began with the exploration of specific materials including C-glass reinforced with a two-part epoxy matrix (resin), fiberglass, and polyester. We applied the soaked glass onto a flat non-stick surface. The goal was ultimately to produce light, rigid or semi-rigid, and, most importantly, nearly transparent pieces that can move with no problem.
Pop-Op’s electronic control system provides a reliable and flexible method for controlling the motion of the wall. Once installed, the timing of the actuations could be readily changed by modifying and uploading a computer program.
Pop-Op contains 37 controlled components (28 panels and 9 flowers). To simplify the electronic hardware design, the control system is designed around the principle of control channels. Each panel and flower was grouped into one of 16 channels. The channels were individually controlled by choosing the time each would actuate. All components within a channel actuated at the same time.
The heart of the electronic control system was the Arduino microcontroller board. The Arduino is an open-source hardware and software prototyping platform. Using a series of input and output pins, the Arduino can be programmed to monitor and control an environment using a C/C++ based programming language. Before construction began, a schematic of the circuit was created in the prototyping software Fritzing.
The electric current required to actuate the SMA wires far exceeded the maximum current output of an Arduino pin. For this reason, some type of transistor was needed to act as a switch for a higher-capacity power supply. The transistor used for the Pop-Op electronic control system was a Logic Level N-Channel MOSFET.
Because the Arduino contains only 16 output pins, directly connecting the Arduino to the 16 MOSFET channels would require all of the Arduino output pins. In order to compensate for this shortage, an integrated circuit known as a shift register was used in the design to extend the number of input/output pins. Using just three Arduino output pins, two shift registers were able to control all 16 channels. The wall was designed to run autonomously throughout the day and then turn off at night. This was achieved by using an external battery-operated clock that interfaced with the Arduino. The Arduino received time information from the clock and was programmed to turn on or off at specific times of the day.
An onboard LCD monitor displayed the status of the system and which channels were currently actuating. In addition, it displayed the system time to ensure that the external clock was set correctly.
1. Deleuze, G., Francis Bacon: The Logic on Sensation, University of Minnesota Press, Minneapolis, 1991.
2. Sommers-Hall, H., Deleuze and Merleau-Ponty: The Aesthetics of Difference. 2008. http://www2.warwick.ac.uk/fac/soc/philosophy/people/alumni/henry-somers-hall/deleuze_and_merleau-ponty_-_aesthetics_of_difference_-_henry_somers-hall.pdf
Designed with Darren Hartl
Dan Whitten. Arduino Automation