2020
Symphony in Sand
Client_ SCI 6317 | Material Systems Digital Design and Fabrication | Final Project
Collaboration_ Katrina Armistead
Timeline_ 6 week project | September - October 2020
Abstract_
Symphony in Sand seeks to explore how music can be compositionally translated into transient art. The interest in investigating the possibilities of mechanically manipulating sand was inspired by several precedents. Foremost was the time-honored technique of sandpainting, mastered by the Tibetan monks who have used this expression for centuries to build sand mandalas by hand. Other influential inquiries into manipulating sand was Factum’s “Material Sound'' which tested sand movement actuated by sound vibrations. Besides material manipulation, Symphony in Sand also seeks to test how audio can be an input in an additive manufacturing process. Symphony in Sand is in part an exploration of how aspects of the senses can be manipulated such as ‘seeing sound vibrations’, and part a critique of how fleeting the cadenza of a masterpiece can be.
01 workflow_
Starting with .mp3 audio files pieces from YouTube, we wrote a script in P5.JS (a JavaScript library) that would record the first 20 seconds of our song and store the music's amplitude values in a Tab Separated Value (TSV) file. We uploaded the TSV to Grasshopper3D and shaped the amplitude curve to create circular shapes on the X and Y axis. Afterwards, we exported the Grasshopper file to Rhino3D where the individual points were divided up (GCode) to create a toolpath for our CNC machine.
To interpret the musical composition, we identified three input variable based on a song’s amplitude, tempo (BPM), and key. By mapping the variables to various mechanisms we could transform music into 3D sand objects.
02 end effector design_
Our CNC machine used a driver connected to one stepper motor to control the end effector. We needed to decide whether our extruder would operate as an additive process, similar to most 3d printers printing filament, or whether it would be subtractive, and carve out sand. The challenge in creating an extruder for an additive process, was that we had to account for multiple setting to satisfy our variables (i.e. changing color of sand, increase or decrease the rate of sand deposition). Our experimentation began with prototyping various geometries made from paper and cardboard before moving into Fusion 360 to model sand delivery and deposition methods
Final end effector used a pinwheel to gradually change the flow rate and had two chambers to hold the two colors of sand.
03 initial design tests_
FIRST DESIGN TEST | Pen
Don't Jealous Me - Beyonce (Test 1)
Don't Jealous Me - Beyonce (Test 2)
Our first attempts with pen required further calibration of the CNC machine and digital variables and our end effector needed to be tightened.
After smoothing the path, increasing the acceleration, and reducing the number of points, our path rendered more accurately.
SECOND DESIGN TEST | Sand
Don't Jealous Me - Beyonce (Test 1)
Don't Jealous Me - Beyonce (Test 2)
Amplitude curves were too close together, making the rings difficult to differentiate due to the large flow rate. After expanding the digital curves in test 2, it was easier to see the amplitude variations. Because many of the geometries consisted of over 1500 points, initial iterations took a long time to print. This was mitigated by smoothing the curve, reducing some of the points, and increasing the acceleration from 10 to 1000 (mm/s2). These adjustments allow for an accurate representation of the amplitude curves while reducing the print time.
THIRD DESIGN TEST | Subtractive Manipulation
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If accuracy was the most important factor, a smaller diameter tool or additional materials such as feathers or rakes might be explored. However, strict adherence to form is not the dominant goal. An additive method of sand deposition better illustrates the process of musical composition and performance.
FINAL DESIGN TEST | Minute Waltz (Op. 64, No. 1), Frédéric Chopin
FINAL DESIGN TEST | Don’t Jealous Me, Beyoncé
FINAL DESIGN TEST | Could You be Loved, Bob Marley
One interesting and unexpected factor is that the noise from the motor was in fact helpful when working with sand because it helped prevent some of the buildup caused by the funnel’s rough material. The funnel section containing orange was slightly more rough than the blue, causing issues when printing. Jostling the funnel helped the sand flow, but future iterations should evaluate different material selections for smoother and better performance.
04 conclusion_
In future iterations, tighter tolerances in the end effector, closer proximity to the deposit field, and smoother materials should massively reduce friction and noise. These improvements to the physical workflow will allow greater dexterity in printing with sand, while still allowing for slight variations in results each pass.
For the digital workflow, lessening the points, increasing the amplitude, and increasing the white space between spirals would likely improve the results by better differentiating between outputs.
Symphony in Sand explored methods of sand manipulation with the SCI 6317 CNC machine, resulting in a process that pulls specific variables from music to portray as transient physical art. The limitations of time, tolerances, and materials directed the process to focus on functional abilities within those constraints. The most recent iteration showcases the manipulation ability of the bespoke end effector and the ability to differentiate between songs based on the selected variables.