Locomotion and Control of a Friction-Driven Tripedal Robot
This work addresses precise locomotion control for small robots in dynamic environments, but it is incremental as it builds on existing control methods.
The paper tackled the control of a friction-driven tripedal robot by developing a mathematical model and gait map for omni-directional motion, resulting in a 46% reduction in path error with a proportional-integral controller and a 65% reduction under aerodynamic disturbances.
This letter considers control of a radially symmetric tripedal friction-driven robot. The robot features 3 servo motors mounted on a 3-D printed chassis 7 cm from the center of mass and separated 120 degrees. These motors drive limbs, which impart frictional reactive forces on the body. Experimental observations performed on a uniform friction surface validated a mathematical model for robot motion. This model was used to create a gait map, which features instantaneous omni-directional control. We demonstrated line following using live feedback from an overhead tracking camera. Proportional-Integral error compensation performance was compared to a basic position update procedure on a rectangular course. The controller reduced path error by approximately $46\%$. The error compensator is also able to correct for aerodynamic disturbances generated by a high-volume industrial fan with a mean flow speed of $5.5ms^{-1}$, reducing path error by $65\%$ relative to the basic position update procedure.