Kinematic walking and posture control of CR200 for subsea exploration in high tidal current

This paper presents kinematic walking and posture control of Crabster (CR200), 200 meter-class six-legged ROV, for seabed survey and underwater precision work in high tidal current. CR200 can overcome the high tidal current by controlling its body posture and walk without overturn. In order to control the body posture and walking, kinematic gait algorithm has been developed. It creates the joint paths of each leg for the desired body posture and position. In order to implement the gait algorithm, two types of graphic user interfaces (GUI) are developed: test program and pilot program. Test program is used for ground test of CR200. It performs basic function for controlling the posture and walking of CR200. Pilot program is developed based on the test program. It has many functions for sea trials of CR200 such as status monitoring of the robot, checking body posture through virtual 3D viewer, sensor power control and so on. In this paper, we will show the simulation and experimental result of the posture and walking control of CR200 based on the gait algorithm using the pilot program. From the results, we verified the effectiveness of the computation frame of the kinematics.