Development Of Controlling System Of Manipulator Of Mobile Robot For Pruning Hedge

Hedge-pruning is labor and time-consumed and dangerous job on express way and highway, so it is trend to substitute robot for labor. Study on realization of multi-purposed mobile robot, funded by Nanjing Forestry University, was put forward for hedge-pruning and grass-cutting .The mobile robot which is composed by a mobile vehicle and 4 DOFs manipulator will move without man's interfering and prune hedge and grass automatically. The dissertation is a part of multi-purposed mobile robot, which included architecture of mobile manipulator ,geometric center line and controlling method for manipulator. Based on controlling mobile vehicle and manipulator separately ,a new architecture was proposed ,in which mobile vehicle and manipulator work in parallel ,if necessary, they can coordinate in task level. Mobile base adopted deliberate and behavior hybrid architecture, while continuous and discrete event architecture was used by manipulator. Hard real time and soft real time was utilized by Communication between them. Chromatic space operator segmented object from environment on the basis of color and cultivated character. Effective and efficient Segmentation was illustrated by experiment with change of brightness in the period of the noon and sunfall. World coordinates of geometric center line of pruned plane was acquired by combination of Ultrasonic sensor and CCD camera. Hedge-cutting was implemented by 4 DOFs manipulator. Direct and inverse kinematics equation was given according to D-H method. Dynamics equation derived by Lagrange-Euler method provided the reference for motion controlling of manipulator and selection of servo motor. Manipulator is coupled with mobile vehicle kinematically and dynamically. Sensor system could overcome kinematic effect ignited by mobile base. Based on controlling the mobile base and manipulator respectively , coupled dynamics from mobile vehicle was viewed as load disturbance. In order to simplify controlling law, position control was used, and that combination of FCMAC controller and PID controller was introduced to control servo motor for the sake of decreasing the effect of load disturbance on control accuracy .