Research On Motion Stability Control Of A Bionic Kangaroo Robot

Bionic hopping robot has a strong ability to overcome obstacles and adapt the environment.However,due to the shorter control time in the robot motion and the uncertainty of the movement in the vacated stage,the stability of motion is very important for bionic hopping robot.Based on the analysis of the robot's mechanical structure and motion process,the motion stability of kangaroo robot is studied in this paper and the main contents are as follows:1.Take-off position control based on sliding mode controlIn order to solve the take-off position control problem for a bionic kangaroo robot which can swing its tail to keep balance,an attitude adjusting method of the robot is proposed using a three-link dynamic model.The mechanism analysis is performed on the robot physical system and then a three-link dynamic model is built for the kangaroo robot.The stability conditions of the robot at the predetermined take-off positions are calculated by using the center of gravity projection method.The robot dynamic model is then transformed into an affine nonlinear form,and a sliding mode controller is designed using the equivalent control method and the controller stability is proved.Simulation and physical experiment results show that the kangaroo robot can quickly reach the required take-off positions.The proposed method can realize the take-off position control of the kangaroo robot with good robustness.2.Hopping motion control of kangaroo robot based on SLIP modelIn order to solve the problem of motion stability of kangaroo robot,the model structure of kangaroo robot is simplified.By analyzing the robot motion process,the SLIP model is established as the robot dynamic model,in which the support and phase transition conditions of the SLIP model are analyzed,and the effective conditions for the robot motion of SLIP model are derived.Forward speed control and jump height control for the robot SLIP model are studied respectively.The proposed method for periodic hopping motion of the simulation robot model using ADAMS is verified.3.Kangaroo robot control system and experimental verificationThe electronic control system of the kangaroo robot is designed,in which a multisensor system including such sensors as the potentiometer,the magnetic encoder,and the gyroscope accelerometer is built to acquire the postures and attitudes of the robot,and the storage and release of motion energy,balance control and communication mechanism of the robot are realized in the main control board.The standing balance control is tested on the robot prototype.