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:
- Bill Goodwine
(now at Notre Dame) - control on stratified sets, with application
to legged locomotion
-
Richard Mason - quasi-static posture planning and (more recently)
aquatic locomotion
- Kristi Morgansen
- Jim Ostrowski
(now at University of Pennsylvania) - nonholonomic mechanics and
locomotion
- Greg Chirikjain
(now at Johns Hopkins University) - Hyper-redundant Locomotion
-
Jim Radford
- Patricio Vela
Pictures
of robots used in locomotion research