Design And Motion Planning Of A Small Biped Robot

In recent years, the research and application areas of robots keep expanding. And especially the research of humanoid robots has received widespread attention, and become one of the hot areas in robotics community. The ultimate goal for humanoid research is to develop an intelligent robot that possesses human features, perform service for human, and live in harmony with human. The biped walking is one of key techniques of humanoid robots. Steadily, naturally and quickly walking is the humanoid robot's chief mark that distinguishes them from other robots. The thesis aims to design a kind of small biped robot, and design its waking gait to make it walk steadily.Firstly, existing biped robot designs are analyzed from the perspectives of the robot mechanical structures and configuration of DOFs. And a new biped robot system is designed. Considering the features of the human body and according to the principle of morphology bionics, the size and proportion of robot is designed be close to the human body. Serial structure is utilized, on the basis of robot function, the least configuration scheme of robot's DOFs is chosen, micro servo motors are used to actuate the robot.The robot gait off-line is planned based on the method of constraint equation. Taking the track of robot's COG and foot motion to be the constraint condition of the gait planning, consideration the velocity change characteristic of robot' gait in a integrity walking process, robot walking can be divided into five periods, corresponding to five kinds of gait. Make sure the continuity of motion of robot, separately calculate the joint motion track of five kinds gait, and combine the calculated result to be an integrity gait. The planning result is simulated and tested.A method is introduced to solve torsion problem of the robot's body when the robot is walking. The robot's body is simplified to be a torsion bar model in horizontal plane, and the arms and legs of robot are regarded as a single pendulum model, the moment of swing leg is balanced by acting on robot's body with the swing of arm, so that to avoid the torsion of robot's body. The arm's motion track is planned from the planned motion of legs. After that, kinematics simulation of the robot is done in ADAMS, the data obtained from simulation are analyzed, and the planning result is evaluated. At last, the planning result is used to conduct walking experiments. In the experiments, robot achieves stead walk, which proves that the result of gait planning is correct.