Case Study | Tunable Lighting & Acoustics
Introduction
Our objective for the preliminary design of an adaptive lighting and acoustic array, was to create a jumping off point for further exploration. The development of version 1 served as an introduction to the design of dynamic integrated lighting and acoustic products themselves, and also to the development of a custom, in-house acoustic analysis and optimization tool set.
Dynamic Acoustic Control
The implementation of flexible felt and wood-veneer composite panels, which can be rotated and twisted by a series of stepper motors, allows the system to achieve a multitude of physical shapes, and thus a multitude of acoustic performance profiles. Composite panels double as absorbers on one side, reflectors on the other, and diffusers when twisted. The emphasis on flexible materials and simple actuators means fewer motors and mechanical linkages, and less maintenance. It also means a nearly limitless set of combinations of twists and orientations to choose from.
Fig. 1 - Empty Room - Resonance Time: 1.29s
Fig 2. - Tunable Acoustics Felt Downwards - Resonance Time: 0.92s
Analysis
We use ray-tracing to simulate sound propagation with a room, given its geometry and the acoustic properties of its materials. Reflection, and absorption are taken into account, in order to determine the resonance experienced at different locations during a particular acoustic scenario. For example: how much echo are people sitting around a meeting table experiencing during a presentation? We use these techniques to identify acoustic problem areas, in order to improve the comfort of everyone in the space.
Optimization
With such a large design space to navigate, it becomes necessary to employ generative design techniques, in concert with simulation, to narrow it down. Using evolutionary algorithms, it is possible to solve for the optimal twist and orientation of each panel, in order to reduce the reverberation during a particular acoustic scenario. By employing these tools, we can narrow the potential states of the array from the billions, down to just ten or twenty top contenders. From there, we can compare the pros and cons of each, to determine the best one for a given situation. This way, we can build up a series of twist and orientation profiles to transition between, in order to offer the best acoustic environment for any scenario.
Build
Our design's build was intended to complement the simple and effective two-point twisting veneer and felt concept we explored in our research. Just utilizing a linear array of stepper motors, we arrived at a simple yet structural CNC housing design that our company was familiar with manufacturing with our own products. The final build resulted in having 4 housings per side which conceal 5 stepper motors each. The housings slot into two suspended aluminum channels with clevis pins and then stabilized with 2 crossbars. The veneer and felt panels can then easily flex and fit into the secured motor shafts and lock in place with embedded slip rings. And lastly, for the light we thought it was best to use a remote driver system with the driver mounting to the ceiling for an elegant approach that left no shadows with the uplighting.
