Analysis and benchmarking of a Whegs™ robot in USARSim

Abstract

Simulation of robots in a virtual domain has multiple benefits, including serving as a training tool for end users and serving as a tool for robot testing and development. USARSim (Unified System for Automation and Robot Simulation) is a simulation tool that is being used to accomplish these goals. It is based on the Unreal Tournament 2004 gaming engine, which approximates the physics of how a robot interacts with its environment. A family of robots that can benefit from simulation in USARSim are Whegstrade* robots. Developed in the Biorobotics Laboratory at Case Western Reserve University (CWRU), Whegstrade robots are highly mobile ground vehicles that use abstracted biological principles to achieve a robust level of locomotion, including passive gait adaptation and enhanced climbing abilities. This paper describes a Whegstrade robot model that was constructed and benchmarked in USARSim. The model was given the same kinds of physical characteristics found in real Whegstrade vehicles. With these traits in place, a validation study was performed for the simulation by comparing the rotational body motions of the virtual and real robot. Specifically, we examine the robotpsilas pitch and roll ranges and frequencies (found to be about 10 degrees to 12 degrees and 5.5 Hz respectively). By altering the simulation parameters in a physically relevant way, the virtual robotpsilas performance was moved to be more in line with these values.