Design and simulation of woodland chassis imitating goat gait

  Objective  The terrain of China’s forest region is more complex, and the performance of woodland chassis determines whether the forest equipment can go up the mountain into the forest, which is the basic problem to be solved in the process of forestry modernization. Compared with wheeled and crawler chassis, the leg independent motion of foot chassis makes foot chassis more flexible and adaptable in the complex terrain environment of forest region. Therefore, the research and development of forest foot chassis for China’s forest environment is of great significance to China’s forestry development.

  Method  In view of the study of gait planning of the forest floor, the general walking gait of goats was analyzed, and the walking step sequence, the relationship between the joint angles and the range of changes were obtained. A woodland chassis was designed, and the structure diagram of the left front leg was analyzed. The working space of the foot end of the chassis was calculated by Monte Carlo method, and whether it can meet the requirements. According to the actual needs, the gait and joint driving of the woodland chassis were determined. The virtual prototype model of the woodland chassis was designed and simplified by ADAMS simulation software. The simulation of the diagonal running gait was carried out. The running performance of the woodland chassis was analyzed by the displacement and speed curve of the mass center of the woodland chassis.

  Result  The movement of the mass center of the woodland chassis in the plane movement was stable in the forward direction, with the forward speed of about 0.2 m/s; the lateral displacement of the chassis mass center was relatively small, and basically advances along the set track; the center of mass fluctuates up and down in the vertical direction, and the fluctuation range accounted for about 1.04% of the total height of the chassis. There was no jumping or tilting of the woodland chassis during the forward process.

  Conclusion  The simulation results show that the gait planning can meet the motion requirements of the woodland chassis, improve the motion stability and terrain adaptability of the woodland chassis, and is safe and reliable, which is suitable for forestry power chassis.