Posture Reconfiguration and Navigation Maneuvers on a Wheel-Legged Hydraulic Robot

Wheel-legged hybrid robots are known to be extremely capable in negotiating different types of terrain as they combine the efficiency of conventional wheeled platforms and the rough terrain capabilities of legged platforms. The Micro-Hydraulic Toolkit (MHT), developed by Defense Research and Development Canada at the Suffield Research Centre, is one such quadruped hybrid robot. MHT's relatively small size, mobility, actuation and locomotion types fill a gap in military unmanned ground vehicles (UGVs). Previously, a velocity-level closed loop inverse kinematics controller had been developed and tested in simulation on a detailed physics-based model of the MHT in LMS Virtual. LabMotion. The controller was employed to generate a variety of posture reconfiguration maneuvers, such as achieving minimum ormaximum chassis height at specific wheel separations. In this paper, the aforementioned inverse kinematics controller was adapted to function on the physical MHT. Several test maneuvers, including chassis height and pitch reconfiguration and uneven terrain navigation maneuvers, were implemented on the MHT and the robot's performance was evaluated.