The Researche On Trajectory Planning Of The Boom Frame For The Forest Work Vehicles

My country’s forest areas have diverse terrain and complex environments.The level of mechanization of forestry equipment directly affects the production efficiency of forest operations.With the adjustment of my country’s forestry strategy,it is necessary to further improve the level of forestry mechanization.The woodland work vehicle has good mobility and can realize the work of wood clamping and transfer,but manual operation has certain hidden dangers and it is difficult to ensure the work quality.Therefore,it is of great significance to study the trajectory planning of the woodland work vehicle.In order to improve the working efficiency of the forest working vehicle,this paper takes the boom system of the forest working vehicle as the research object,studies and analyzes the trajectory planning of the boom based on the kinematics theory of the manipulator,and proposes a particle swarm algorithm that dynamically adjusts the learning factor for the boom.The running time of the joint trajectory of the frame is optimized.The main research contents and results of the paper are as follows:(1)According to the boom structure of the forest work vehicle,the kinematic model of the boom was established by the D-H method,and the forward and inverse kinematics of the boom of the woodland work vehicle were analyzed.The Robotics Toolbox was used to verify the accuracy of the boom kinematic model.In Matlab software,Monte Carlo method is used to simulate and analyze the working range of the boom end working device,and the accuracy of the working range is verified.(2)The trajectory planning methods of the boom in joint space and Cartesian space are studied.In the joint space,polynomial interpolation,linear interpolation with parabola,and spline interpolation trajectory planning are performed on the boom joints respectively.Joint 2 is used as the trajectory planning method.For example,the trajectory curves of the boom under different interpolation methods are compared and analyzed,and the results show that the 3-5-3 piecewise polynomial interpolation can not only ensure the acceleration,but also improve the joint operation efficiency.(3)Based on the speed planning algorithm and the interpolation algorithm,the trajectory planning of the end working device in the Cartesian space is carried out.By deriving the Jacobian matrix and the geometric relationship between the driving device and the joint motion,the Cartesian space,the joint space and the driving space are realized.The mutual conversion between the trajectories,using Matlab software to simulate the straight line and arc trajectory in space for the end working device of the boom,the results show that the combination of the S-shaped speed planning algorithm and the interpolation algorithm can effectively ensure the stability of each joint of the boom and the driving device.run.(4)The application of particle swarm optimization in trajectory optimization is studied.Aiming at the problem that particle swarm optimization is easy to fall into local optimum,an improved method of dynamically adjusting the learning factor is proposed.The results show that the improved particle swarm optimization algorithm is more efficient,and can effectively improve the working efficiency of the forest work vehicle.