Robotic Locomotion

Our current work is aimed at developing a more unified theory for the analysis and control of robotic locomotion. Our investigation of a more unified approach began with undulatory locomotion. Undulatory robotic locomotion is the process of generating net displacements of a robotic mechanism via periodic internal mechanism deformations that are coupled to continuous contstraints between the mechanism and its environment. Actuatable wheels, tracks, or legs are not necessary. In general, undulatory locomotion is ``snake-like'' or ``worm-like,'' and includes our study of hyper-redundant robotic systems. However, there are examples, such as the Snakeboard, which do not have biological counterparts. From a mechanics perspective, undulatory systems are often characterized as Lagrangian systems which exhibit symmetries and which are subject to nonholonomic kinematic constraints. The interplay between the conserved quantities which would arise from the symmetries (in the absence of nonholonomic constraints) and the constraints is fundamental to the locomotion process. Toward this end, we have been developing a control theory for mechanical systems with symmetries and constraints.

More recently, we have been extending our basic framework for undulatory locomotion in two directions. First, the basic theory can be extended to systems with discontinuous contstraints (such as legged systems) by modeling such systems on stratified sets (see the applied control theory section). Second, preliminary work has shown that mechanics of a number of aquatic locomotion schemes also fit into the same framework. See this page for descriptions, pictures, and videos of our fish work. This page also has some details on our robot fish work.

Students/postdocs (current and former) that work in this area:

Selected Papers

Pictures of robots used in locomotion research