CLAWAR 2004, Madrid, Spain A CLAWAR That Benefits From Abstracted Cockroach Locomotion Principles

MechaRoach II is a hexapod robot under development that will walk on horizontal surfaces, climb on inclined or vertical mesh surfaces, and test strategies for transitioning between the two. The locomotion principles that allow cockroaches to make these transitions have been studied and mechanisms using abstractions of those principles have been developed for the robot. These principles include leg and foot morphology, gait adaptation, and body flexion. MechaRoach II will have a single drive motor, a motor for steering, and a motor to actuate a body flexion joint. The single drive motor will power all six legs, and each leg will use 4-bar mechanisms to recreate cockroach-like foot trajectories. Cockroaches have been shown to flex their bodies downward between the first and second thoracic segments or rear their bodies upward using their middle legs during transitions between climbing on vertical surfaces and walking on horizontal ones. Similarly, MechaRoach II’s body joint will be used to rear the front of the robot upward or downward during transitioning. The robot will normally walk in a tripod gait with contralateral legs 180 degrees out of phase, but will use passive torsionally compliant devices to bring contralateral legs into phase for climbing.