A platform for dynamic simulation and control of movement based on OpenSim and MATLAB

Area of Science:

• Biomechanics
• Computational Biology
• Control Systems Engineering

Background:

• Numerical simulations are crucial for complex engineering and medical applications.
• Existing tools like MATLAB/Simulink and OpenSim offer distinct strengths in modeling and simulation.
• A need exists to integrate these platforms for comprehensive biomechanical analysis.

Purpose of the Study:

• To develop and validate a novel interface between MATLAB/Simulink and OpenSim.
• To enable advanced human movement simulations by combining model-based design with dynamics simulation.
• To facilitate the creation of new treatment strategies for musculoskeletal disorders.

Main Methods:

• Integration of OpenSim within MATLAB/Simulink via the S-function mechanism.
• Demonstration using both open-loop and closed-loop control systems.
• Validation with an arm model for forward dynamics and feedback control simulations.

Main Results:

• The interface successfully reproduced OpenSim Forward Dynamics Tool results with minimal RMS error (0.03° shoulder, 0.06° elbow).
• MATLAB's integrator accelerated forward dynamic simulations by over 50% (7.1s to 2.9s).
• A closed-loop system demonstrated effective pole balancing using a PID controller against disturbances.

Conclusions:

• The developed interface effectively integrates OpenSim and MATLAB/Simulink.
• This integration enhances capabilities for simulating human movement dynamics with feedback control.
• The tool empowers researchers and clinicians to develop innovative solutions for musculoskeletal conditions.