Research On Trajectory Planning And Simulation Of Excavator Robot

To achieve autonomous mining function of excavator robot, this paper research on the excavator robot of trajectory planning method. First of all in the D-H coordinate system established sketch of working device of excavator robot,completed kinematics and inverse kinematics analysis, realizes the mutual conversion of the pose space and joint space. Combined with the structure parameters of a excavator robot, conduct excavator robot workspace simulation analysis, selecting operating region, setting up reasonable mining key points,space spline curve interpolation method was used to obtain a excavator robot space mining path.Through the robotics toolbox for trajectory planning problem research,establish the linkage model of the excavator robot. realized the forward and inverse kinematics simulation, complete path simulation in Cartesian space and point-to-point trajectory planning simulation. According to the method of trajectory planning can only meet the characteristics of point-to-point motion planning, further by using the Matlab software, completed joint space trajectory planning algorithm programming, simulation trajectory planning research.For the realization of the excavator robot continuous path mining process planning, proposed 2 types of trajectory planning algorithm in joint space,namely: joint space piecewise polynomial interpolation method, including3-3-5-3-3,3-3-3-3-3,3-3-3-3-5 the piecewise polynomial interpolation; and joint function space quasi legitimate, including the n-degree polynomial fitting method and Fourier series fitting method, and the trajectory planning method for simulation. Comparison shows various trajectory planning method for the applicable conditions, advantages and disadvantages.Select the piecewise polynomial 3-3-5-3-3 trajectory planning method,combined with the working device of the dynamics characteristics, puts forward a new piecewise variable order polynomial optimization method, for the results of trajectory planning order acceleration jump greatly, beyond the limit of the trajectory polynomial segment, through the joint acceleration constraint value,inverse solve polynomial correction of the highest order number, quadratic programming, and the simulation of trajectory planning, to meet the requirements of the working device structure dynamic characteristics.For before and after the amendment of the obtained results of trajectory planning, through the forward kinematics calculation, the joint space trajectory planning results mapped to the bucket in the Cartesian space path, with advance planning of mining path for comparison, get conclusion that the modified before the amendment of the size compared to the pre planned path, the error is smaller,the accuracy is more higher.The optimized segmentation variable order polynomial trajectory planning method, can complete robotic excavator continuous path of the of tasks,continuous and stable working process, the precision is higher. It can also satisfy the dynamic characteristics of the working device structure requirements.