Research On Manipulator Grabbing System Based On Machine Vision

In recent years,with the development of technology,the manipulator has been widely used in industrial production because of its high working efficiency.However,the traditional robot manipulator usually performs target grabbing work with the established procedures,and is unable to accept external information.When target position changes,the control program must be resettled.Therefore,following the current development trend of intelligent manufacturing,combining machine vision technology with manipulator control technology,and improving the intelligence degree of the manipulator has important research significance and application value.To overcome the limitations of the traditional manipulator,this paper uses the Kinect v2 vision sensor and the six-axis robot manipulator as research objects and applies the machine vision technology in grabbing task,so that the sensing ability of the manipulator grabbing system will be improved and the autonomous grabbing function of the manipulator will be realized.Firstly,according to the task requirements of the system,this paper will design overall scheme of the system,analyse and select software and hardware modules in the system.Secondly,this paper will research and analyse visual recognition and positioning technology,calibrate the Kinect v2 sensor by Zhang's Method and analyse the relationship of coordinate transformation,in order to obtain the internal and external parameters of the camera.The image will be pre-processed by analysing and selecting the image greying,filtering,threshold segmentation and depth segmentation method.To overcome the shortcomings of the traditional template matching method,this paper uses the improved template matching method based on the contour Hu moment feature to complete the target recognition and realize the target spatial coordinate positioning.Then,according to the D-H parameter method and the hardware structure parameters of the manipulator,this paper will analyse and compute the positive and inverse kinematics of the manipulator,and after comparison and analysis the fifth-order polynomial interpolation method in joint space will be used as the trajectory planning method.Then,according to the structural parameters of the physical manipulator,the manipulator model under the ROS platform will be created with 3D modelling software.Based on the model,the manipulator trajectory planning algorithm will be simulated and verified by the Rviz tool,which lays a foundation for the realization of the grabbing system.Finally,this paper will complete the construction of the whole visual mechanical manipulator grabbing system and integrat the software modules based on ROS platform.Besides,the experiments of location and target grabbing functions will be designed to verify the accuracy of the identification and the success rate of the system's self-acquisition.The results of error analysis show that this visual robot manipulator grabbing system is able to meet the needs of the grabbing task.