Research Of Trajectory Planning For The Working Device Of Autonomously Excavating Robot

Excavator is one of the most widely used engineering machinery,which plays an important role in the mining,construction,transportation and other fields.With the increasement of the working environment and the task difficulty of the excavator,the intelligent and automatic excavating equipment is developed rapidly.Combined with the research status of excavating robot at home and abroad,research of the trajectory for the working device of excavator using the robot planning,automatic control and sensor technology is the key to realize from the traditional manual operation to the excavator working independently.In this paper,the research of the working device of excavator is mainly as follows:1.System modeling analysis of the working device.Firstly,the structure and common working conditions of the excavator are introduced;secondly,the traditional hydraulic excavating system is analyzed and modified,and then the electric signal is controlled by the upper controller to control the proportional valve electromagnet to replace the manual control of the handle,and a closed loop position control is arranged on the displacement sensor installed on each hydraulic cylinder.Finally,the movement space of the robotic excavator is drawn by using the model parameters,and the target space is analyzed by task planning.2.The hydraulic system loop is analyzed and the model of the hydraulic system for the working device of excavator is established,and effects of pressure and flow rate on the performance of the system are analyzed.The kinematics of the robotic excavator is analyzed by the coordinate transformation and geometric method to realize the conversion of the configuration space to the drive space of the hydraulic cylinder.The linear transformation for the bucket tip operating speed and the joint speed is realized by using the Jacobian matrix and its derivative matrix of time.3.Considering the common fixed mining operations,the solving method of the trajectory planning is proposed by taking into account the rapidity and stability in the working process of excavating robot.The mathematical model of the optimal trajectory of the working device is established by using the three spline curve fitting,and the model is optimized by the genetic algorithm module in Matlab.4.The virtual prototype model for the working device of excavating robot is established in ADAMS,and the simulation of the kinematics and dynamics are analyzed by the joint angle and the hydraulic cylinder drive data,which is obtained by the trajectory planning.The optimal trajectory of the bucket tip and the force condition of each hinge point are obtained in the simulation conditions.It is satisfied the task requirements by respectively compared with the desired trajectory.It is shown that the simulation analysis of the bucket trajectory of excavating robot has achieved the desired effect and meet the working process of the requirements of rapidity and stability through the above research results,and it has an important significance to further realize the intelligentization of engineering machinery.