A tendon-driven biomechanical robotic arm inspired by human anatomy. Actuation via TCP nylon muscle fibers (Twisted and Coiled Polymer) + nichrome heating — mirroring biological muscle hierarchy from fiber to fascicle to muscle to arm.
TCP muscles contract when heated (nylon shrinks) and relax when cooled (passive return). Multiple strands bundle into fascicles, fascicles bundle into muscle groups, and Kevlar tendons transmit force to joints. This creates a bioinspired system that is:
| Component | Material | Function |
|---|---|---|
| Bones | Aluminum/brass tubing | Structural frame, tendon routing |
| Joints | 3D-printed resin + PTFE | Low-friction rotation |
| Tendons | Braided Kevlar/aramid | Force transmission |
| Muscles | TCP nylon + nichrome | Actuation (contract) |
| Control | ESP32 + MOSFET + PWM | Muscle switching & modulation |
Core actuator unit: 4-layer structure, assembly steps, electrical connection
Read Fascicle Guide →Elastic tendon storage, two-tier recruitment, fluid cooling for faster response
Read Speed Architecture →TCP vs McKibben vs DEA analysis, hybrid design, power budget, open questions
Read Research →The arm's musculature maps 4 major muscle groups in the prototype:
| Location | Muscle Group | Action | Fascicles |
|---|---|---|---|
| Upper arm (front) | Biceps | Elbow flexion | 3 |
| Upper arm (back) | Triceps | Elbow extension | 3 |
| Forearm (palm side) | Flexors | Wrist/finger flexion | 3 |
| Forearm (back) | Extensors | Wrist/finger extension | 3 |
Total: 4 muscle groups, 12 fascicles
