Aiming at the problems of the traditional caisson foundation construction equipment,such as low earth taking efficiency,poor formation adaptability and blind area in the operation area,a caisson foundation earth taking robot was designed.According to the construction requirements,the structure design of the robot was carried out,and the finite element statics analysis of the telescopic arm was carried out to verify the rationality and reliability of the telescopic arm structure design.The forward and inverse kinematics models of the robot were established based on the D-H method and the geometric method,and the kinematic models from the joint space to the driving space were established based on the geometric method.The pose control of the milling head was finally converted to the position control of the hydraulic actuators of each joint.Then,the electro-hydraulic proportional control system driven by the robot joint was designed,and the PID controller was used to correct it.The effectiveness of the control strategy was verified by simulation.Finally,the operational performance of the robot was analyzed by field test.The test results show that the robot can meet the requirements of caisson construction and the expected goal is reached.