Locomotion Control of Ledge Climbing Robot Using CPG Control and Infrared Sensors

Abstract

Climbing along the horizontal ledges on the vertical walls is insufficient for ledge climbing robots because ledges with non-zero pitch or inclined angles are also highly representative application scenarios. To improve the ability to adapt to the various climbing environments, this study presents a locomotion control strategy composed of a central pattern generator based algorithm to perform horizontal ledge climbing and a path planning algorithm to pass through the non-smooth inclined transition. Two sets of infrared sensors are installed on both sides of the robot to acquire environment information and develop an algorithm that detects and estimates the pitch angle change while the robot is transversely climbing along pitched ledges. A gripper posture feedback control system is integrated into the process of horizontal ledge climbing to enhance the robustness against disturbances. Experiments mimicking the ledge climbing scenarios with both negative and positive pitch angles are conducted to justify the effectiveness of the proposed locomotion control strategy.