PELE Musculoskeletal Leg Control

Outcome

I built and validated the PELE end-to-end control stack in C++ (task space to actuator level), integrating electrohydraulic hardware, sensing, and high-voltage drive electronics for agile locomotion.

Problem

Musculoskeletal robotic legs demand compliant actuation and robust control under changing contact and load conditions. This project bridged compliant electrohydraulic actuation with stable, real-time task-space control for locomotion experiments.

System

Mechanics: carbon-fiber leg with hip/knee joints, tendon routing, and antagonistic electrohydraulic muscle packs
Electronics: computer + DAQ + high-voltage amplifiers driving four muscle packs (hip/knee flexor-extensor pairs)
Sensing: joint encoders plus capacitive self-sensing from voltage/current measurements
Control: cascaded controller from task-space planning to joint control to low-level actuator voltage commands
Runtime software: multithreaded C++ pipeline for DAQ communication, control loop, filtering, and logging

Contribution

Controller architecture and implementation in C++
End-to-end integration of mechanical platform, sensing, DAQ, and high-voltage actuator drive
Experimental validation and performance analysis
Co-author on the publication and system reporting

Technical Stack

C++
Real-time control systems (500 Hz loop)
Cascaded task-space, joint-space, and actuator-level control
Musculoskeletal robotic platform integration
High-voltage actuator drive integration
DAQ and multithreaded runtime pipeline
Capacitive self-sensing and encoder-based state estimation

Key Results

500 Hz closed-loop control implementation in C++
Closed-loop task-space tracking of four predefined foot trajectories (ellipse, rectangle, infinity, star) for 20 s tests
Over 5 Hz gait motions with repeatable trajectories
High jumps up to 40% of leg height
Cost of transport (COT) as low as 0.73
~1.2% holding energy compared to an electromagnetic counterpart during squatting
Published in Nature Communications (2024)