Design And Simulation Of Foot Parts Of Humanoid Robot

The humanoid robot's structure is modeled on human design,and has a greater ability to adapt to complex terrain and harsh environments than wheeled robots.However,the foot structure of humanoid robot is still relatively simple and a variety of functions is relatively lacking,so the high mobility and adaptability of humanoid robot in the unstructured environment is unable to show.In this paper,based on the analysis of the research on the foot structure of humanoid robot at home and abroad,the paper studies the design and optimization of the new foot structure of humanoid robot in the view of the above problems.Firstly,the size and function of each component in the foot structure of the humanoid robot are determined by analyzing the composition of the human foot,and a simplified model of the foot structure is established.The simplified model was studied by using inverted pendulum model,and the action stage and motion parameters of each component were determined.At the same time,the stress of the key components in the foot is analyzed,and the data supports the later structural design.Then,the main tandem elastic actuator structure is summarized,and the two-degreeof-freedom flexible ankle joint mechanism is designed for the humanoid foot.The mechanism adds additional freedom and elasticity to the foot of the robot,including the highly integrated parallel hydraulic drive module,the special series elastic actuator and the variable stiffness structure of the Achilles tendon,which improves the movement ability of the humanoid robot and the impact resistance.In the structural design,topology optimization method is used to ensure the strength of structural parts and reduce its weight.At the same time,by comparing the advantages and disadvantages of different compliance methods,the active-passive compliance foot structure is designed according to the different application of the front and rear foot.The passive compliance structure of the rear foot can provide a cushioning effect when the foot is impacted,and the active compliance structure of the fore foot can adapt the robot foot to different terrain environment.According to the ZMP stability criterion,the appropriate sensor network layout is designed for the robot foot.Then,the virtual prototype of the foot structure of the humanoid robot is built,and the foot structure is simulated and the performance test of the key mechanism is carried out.In the motion simulation,the motion parameters of each joint of the foot prototype were obtained,and the walking stage of the robot foot prototype was studied according to the stress curve.In the performance test,the buffer mechanism of the rear foot,the variable impedance mechanism of the front foot and the Achilles tendon energy storage mechanism were tested,and the performance of each institution was analyzed.Finally,the paper summarizes the whole paper and makes a prospect for the future research direction.