Gait generation for two link planar system in viscous environment

Abstract

Research in the biorobotics domain, and more specifically in the domain of serpentine robotics has been focused on mimicking biological locomotion. Furthermore, these under-actuated multi-link robots have been extensively analyzed to generate biological and nonbiological gaits. Two-link systems, being the simplest in this family of mechanisms, have only one controlled degree of freedom consisting of the inter-link angle, a fact that makes its gait generation extremely complex. This thesis analyzes these simple planar systems in a viscous environment in order to generate displacements in different directions. The interaction of the system with the environment will be limited to viscous friction applied to specific friction pads located on the links. The nonlinear equations of motion will be extensively analyzed, resulting in analytical solutions for the location of the pads and the type of input angle required for displacement in two different directions. The analysis is based on qualitative properties of the different terms in equations of motion, which makes it applicable to any system with similar properties. Simulation results for movement in two different directions will validate the different conclusions made throughout the analysis.