Instantiation of LLS Model Using Torque-Based Actuation
An Undergraduate Honors in
the Major Thesis Submitted to the
Department of Mechanical Engineering in partial fulfillment of the requirements
for the degree of Master of Science
Degree Awarded: Spring Semester, 2012
1Department of Mechanical Engineering, Florida State University, Tallahassee, FL 32310, USA
Biological studies have yielded reduced order models that can be used to approximate the dynamics of animals in motion. One such model, the Lateral Leg Spring (LLS) model, has shown to reproduce accurately the ground reaction forces, velocity pro les, and body orientations of biological systems by examining their dynamics in the lateral plane. Despite substantial simulation research performed with this model, an instantiation of this model is yet to exist. The first such instantiation was proposed and initialized by Shillet al. , and presented here is the continued progress of that research. Contributions to this thesis include the finalization of the electrical components of the robot to include a custom-made circuit board. The successful implementation of serial communication between the micro- controllers was achieved through this circuit board to allow for reliable and bidirectional communication between the controllers. The hardware was modified to improve reliability by utilizing new gears and realigning the gear shafts in the legs. A new attachment method is proposed and implemented to make the foot attachment simpler and less cumbersome. Finally, a successful motor control scheme was developed and coded to result in simple, solely torque-based actuation of the robot. These contributions are outlined in this thesis and future work is proposed.