Experiment Videos

This video shows that our ESC-based method is capable of adapting the virtual-constraint based control parameters for amputees with different masses. See our CCTA paper for more details.

This video shows an extremum seeking controller (ESC) for simultaneously tuning the feedback control gains of a knee-ankle powered prosthetic leg using continuous-phase controllers. We developed a cost function whose optimum shifts as walking speed changes. Walking experiments show the effectiveness of ESC to track the optimum across different walking speeds. See our TCST paper for more details.

In this work, we developed a quasi-passive ankle exoskeleton with a variable stiffness mechanism capable of self-tuning. As the relationship between the muscular effort and the optimal spring stiffness across different walking speeds is not known a priori, a model-free, discrete-time extremum seeking control (ESC) algorithm was implemented for real-time optimization of spring stiffness. Experiments with an able-bodied subject demonstrate that as the walking speed of the user changes, ESC automatically tunes the torsional stiffness about the ankle joint.

This video shows an extremum seeking controller (ESC) adapting the control gains of a powered prosthetic leg in benchtop mode.