Journal of Bionic Engineering (2025) 22:118–132https://doi.org/10.1007/s42235-024-00625-0

Guidance and Control of Underwater Hexapod Robot Based on Adaptive Sliding Mode Strategy

Qingshuo Gong1  · Wei Zhang1  · Yu Su1  · Haoyu Yang1

1 College of Intelligent Systems Science and Engineering, Harbin Engineering University, Harbin 150001, China

Abstract 

Animals exhibit remarkable mobility and adaptability to their environments. Leveraging these advantages, various types of robots have been developed. To achieve path tracking control for the underwater hexapod robot, a path tracking control system has been designed. Within this system, a Line-of-Sight (LOS) guidance system is utilized to generate the desired heading angle during the path tracking process. A heading tracking controller and a speed tracking controller are designed based on the super-twisting sliding mode method. Fuzzy logic is employed to establish the nonlinear relationship between the output of the upper-level controller, which includes force/torque, and the input parameters of the Central Pattern Generator (CPG) network. Finally, the effectiveness of the proposed method is verified through simulation and experimentation. The results demonstrate that the robot exhibits good tracking accuracy, as well as stability and coordination in motion. The designed path tracking system enables the underwater hexapod robot to rapidly and accurately track the desired path. 

Keywords Underwater hexapod robot · Path tracking · Sliding mode control