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Unity

Hyperinstrument




  • Role: 
    End-to-end product designer/engineer (solo)
  • When:
    Oct–Dec 2024
  • Focus: 
    Mechanical design, materials, audio enclosure, DFM/DFA, rapid prototyping, test & validation
  • Tools:
    Rhino/Fusion 360, TouchDesigner, Arduino (firmware), FDM/SLA 3D print, PETG/TPU


    • Overview:
    Unity is a hyperinstrument operated through hand motion sensing, featuring distinct units on a circular interface. Each unit contains metal beads of varying sizes, correspond to specific sound frequencies which represented through audio-reactive visuals.
    This project aims to deconstruct traditional approaches to composition and musical performance, positioning design as a bridge between human instinct and artistic expression.






    Problem & Goal
    Traditional digital instruments often feel screen-bound and non-tactile. The goal was to re-introduce physicality—designing a gesture-driven instrument with acoustic feedback that’s
    modular, manufacturable, and robust enough for repeated live use.



    Success Criteria






    Inspiration
    The tambourine inspires the design, which produces sound through hand-driven vibrations.As a music producer, I hope to promote new methods of music creation by providing unique sound-mapping tools and more intuitive body instructions.






    Solution Overview
    Unity is a circular instrument composed of interchangeable “tone units.” Each unit houses metal beads of specific diameters that excite different frequency bands when agitated by hand motion. Gesture data (palm curvature, velocity) is read by sensors; visuals are rendered in TouchDesigner.

    • Tone units (acoustic modules): bead sizes ~3–8 mm correlate to ~2–20 kHz bands (e.g., 8 mm ≈ 2–3 kHz; 7 mm ≈ ~5 kHz; 3–4 mm ≈ ~10–20 kHz).

    • Enclosure: Transparent PETG selected for toughness and crisper collision timbre versus PLA

    • Interaction: Palm curvature + specific gestures modulate timbre; a side push-slider and a tongue-press actuator provide quick mechanical states (stow/perform).





    Engineering Highlights

    Materials & Structure

    • PETG shell: impact-resistant, stable under repeated collisions → cleaner transient response.

    • Wall thickness study: 1.8–2.2 mm candidate set; 2.0 mm chosen to balance mass, stiffness, and print time.

    CAD, Dimensioning & Tolerancing

    • CAD controls: bead cavity diameter, vent size, wall thickness, snap feature depth.

    • Functional dimensioning set from the actuator datum; ±0.15 mm nominal fit on module bayonet to ensure tool-less swap while avoiding buzz.

    • Tolerance stack-up verified on the ring assembly; gate for reprint if radial misfit >0.25 mm.

    DFM/DFA Decisions

    • Modularity: individual tone units as sub-assemblies → quick swap, easier service.

    • Fasteners: reduced count via cantilever snap-fits + 2 captive screws at service points only.

    • Print orientation standardized to minimize support inside acoustic volumes; chamfers added for auto-deburr.

    Audio & Interaction Subsystems

    • Acoustic: internal venting strategy tuned to avoid whistling; PETG resonance tested with bead mass variations.

    • Gesture sensing: hand-motion/palm-curvature features mapped to filter depth and gate thresholds.



    Prototyping & Validation

    Build Iterations

    • Rev A: geometry + enclosure feasibility; found rattle at module seam.
    • Rev B: tolerancing pass; bayonet snap refined for faster DFA.

    Bench Tests

    • Shake-spectrum test: verify bead-size → band map across 5 modules.
    • Rattle test: 60 s high-energy shake; SPL variance < X dB target (define when you log).
    • Drop & scuff: 0.8 m onto rubber mat; no latch failure, cosmetic scuffs acceptable.
    Tip for website: add a small table or sparkline charts for each test.












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