Research Summary

Intermediate Fellowship research summary

Many of us pay little attention to the challenges of stability while walking or running on uneven ground. In the unfortunate event of injury, disease, or old age, stable locomotion becomes a daunting task. Sensory feedback from vision, touch, and spatial perception of the limbs are clearly important for stability. But the muscles in our legs do more than simply power us forward. Muscles also function like shock absorbers to control how the perturbations from an uneven terrain are transmitted up the body. We seek to characterize the relative contributions of the shock absorber like mechanical properties of our leg's muscles versus sensory feedback for maintaining stability on uneven terrain. This could pave the way for new rehabilitation methods for those with injuries or disease, and new designs for prosthetic and robotic legs.

Broadly, we are interested in questions surrounding morphology and control in animals and machines. On the one hand we ask how the body’s structure affects function, namely control strategies. On the other hand, we ask how demands on function shape the body, namely the evolution of animals or the design of machines. Our efforts rely on the use of mathematical models, biomechanical experiments, and robotic devices. We develop mathematical theories to predict the interplay between morphology and control, test those theories using measurements on human volunteers, and when possible, translate our understanding into mechanical analogues.

How to locomote stably on uneven terrain? How to control, and how to learn to control the arm? How to stably manipulate objects using hands? These questions address the relationship between control and morphology in animals, as well as guide prosthetic and robotic design. We use experiments with humans to identify the limits of performance. Mechanical implementations test theories, and guide the design of robots and prosthetics. Mathematical and computational approaches interpret and guide the experiments.