Wireless Shape Memory Alloy (Nitinol) Robotic Claw
Objective & Mechanical Tradeoffs
Robotic end-effectors traditionally depend on bulky electric servomotors and gearboxes that add inertial weight to distal joints and introduce mechanical backlash. Collaborating with Khanjur R&D, our objective was to replace electric motors with resistive Joule-heated Shape Memory Alloy (Nitinol) wire.
- Thermal-Current Control: Engineered high-frequency PWM switching across logic-level N-channel MOSFETs to meter heating current accurately, preventing wire anneal damage while ensuring repeatable closure force.
- Embedded Wireless Server: Programmed custom C++ firmware on an ESP32 microcontroller hosting an asynchronous local Wi-Fi web server, achieving smartphone teleoperation with sub-50ms latency without relying on external networks.
- Hardware Evolution: Iterated through PVC bench rigs, internal ratchet mechanisms, and 3D printed mechanical levers to amplify stroke displacement from subtle alloy contraction.
Actuator Architecture
Prototype Showcase & Actuation Video
Click the large preview to open fullscreen high-resolution inspection.
Final Assembly
Interior View
Actuation Video
Nitinol Thermal Demo
Ratchet Latch
Expo Presentation