Study Of The Design And Motion Simulation For The Hexapod Robot’s Walking Mechanism

The autonomous walking of legged robot in the complex terrain environment is one of the research hotspots in the robotics technology areas. In the nature, the six-legged creatures have masterly physiological structure and agile motion mechanism, so they can easy walk in all kinds of complex terrain environments. In this dissertation, to solve the motion planning problem of the hexapod robot in the complex environment, it is done that the research of optimization design and movement planning for hexapod robot’s walking mechanism, combined with the features of the six-legged creature’s physiological structure. The main contents are as follows:On structure optimization design, the structural features of the six-legged creatures are analyzed, the configuration design of the hexapod robot’s walking mechanism is completed. The structural parameters are optimized with using flexibility as the objective function, the optimization problem for the transmission mode of the walking mechanism is discussed, and the strength check of its key parts is completed.On building mathematical model, the kinematic model of the hexapod robot’s walking mechanism is constructed based on the D-H parameters method, and the kinematic equations of both its swing phase and support phase are deduced. Its dynamic model is constructed based on the Lagrangian method, and the dynamic equations of both its swing phase and support phase are solved.On planning motion program, three aspects of the hexapod robot’s walking mechanism are studied, which including the foot trajectory planning, gait planning and gait stability analysis. Firstly, the foot trajectory planning of both swing phase and support phase are finished by using the polynomial interpolation method, and the issues are analyzed which about angles planning of each joint in the legs. On this basis, the issues about the foot trajectory planning in complex environment are discussed. Secondly, several common basic gaits are researched, and on the basis, one strategy about the gait planning is proposed, which is called as freedom exploring gait in this dissertation. Lastly, the basic gait stability is analyzed in qualitative by using Static Stability Margin, and the static stability and dynamic stability are analyzed in quantitative by using Energy Stability Margin and Zero Moment Point Stability.Finally, on the basis of the above theoretical analysis, the simulation analysis and physical prototype test about two kinds of basic movement of the hexapod robot’s walking mechanism are finished in mechanical system dynamics simulation software. Through the simulation analysis and physical prototype testing, the theoretical researches which including the optimum structural design, the foot trajectory planning, the gait planning and the motion planning in complex environment are verified.