Research On Mobile Manipulator And Its Application In Loading And Unloading

With the progress of science and technology and the promotion of intelligent manufacturing,the full use of artificial production can not meet the development requirements of manufacturing industry.Labor production costs are high,and it is difficult to recruit workers;For some special parts,the production and use of artificial can not meet the requirements of high precision;For the operation of dangerous work,there is a safety hazard in the use of manual;For some tired work,long-term production will also consume a lot of manpower,intangible increase in costs.Therefore,robot replacement for production has become a trend,in line with the requirements of intelligent manufacturing.In response to the needs of enterprise transformation and upgrading and promoting intelligent manufacturing,this project,combined with the school enterprise cooperation project,provided an automatic up and down material production plan for the production of electrical box of enterprises by using mobile mechanical arm.In this context,the relevant research on mobile mechanical arm and its application in automatic feeding and unloading was carried out.The specific research contents are as follows:First,kinematics analysis and modeling were carried out.The forward and inverse kinematics models of manipulator and moving chassis were developed respectively to prepare for the subsequent control;Based on the model,the workspace analysis was carried out.Firstly,the workspace of the manipulator was analyzed independently by Monte Carlo method,and then the static workspace analysis of the whole mobile manipulator was carried out;In order to determine whether the mobile manipulator will overturn under the condition of the manipulator operation,ZMP and FA method were used to determine whether the mobile manipulator will overturn.Secondly,the error of the mobile manipulator was analyzed and the compensation method was proposed.Firstly,the source of the sensor error of the mobile manipulator was analyzed,and the noise reduction and compensation processing were carried out for the sensors with great influence on the error;Secondly,the working error of manipulator was analyzed.The error was mainly caused by the accumulated error of DH parameters,and the final end actuator position and posture deviation;Then,the error of the whole mobile manipulator was analyzed.Finally,the BP neural network technology was used to compensate the whole robot arm error,and all errors were considered as internal errors for comprehensive correction.Then,the work planning algorithm of mobile manipulator which was used for automatic feeding and unloading was studied.Firstly,the work of mobile platform was planned.In order to make the mobile platform adjust the trajectory adaptively,the PID algorithm based on RBF was adopted to modify the trajectory.Meanwhile,the velocity planning algorithm based on the quintic polynomial was adopted to reduce the influence of the inertia of the mobile manipulator on the accuracy of the movement,Then,the multi-sensor fusion technology was used to collect the mileage information of mobile platform for feedback and correction;For the work planning of the manipulator,A* algorithm was used to plan the space path,then B-spline technology was used to smooth the trajectory.For the attitude planning of the manipulator,the quaternion interpolation method was used to supplement the manipulator.Finally,the rationality and feasibility of the planning were verified by simulation.Finally,the prototype design and construction and engineering application experiment were carried out.Because the background of this research topic involved the practical application of the project,the fifth chapter mainly introduced the relevant design and application verification.First,the main hardware of mobile manipulator was introduced,and the hardware of mobile chassis was emphasized;Then,the software system designed by this research project was introduced,which integrates the control system of the manipulator and the control system of the mobile platform.The human-computer interaction part of the software was mainly to meet the practical application of the factory;Finally,the experiment was carried out,and the application of the simulation was emphasized.In this paper,the work accuracy of mobile manipulator was improved from several perspectives.The designed control system can run smoothly.The prototype could complete the related work of automatic feeding and unloading of electrical box under the simulated environment.