An Application Experimental Research Of Fault-tolerant Six-axis Force Sensor For Industrial Robot

As the transform from "Made in China" to "Made with Wisdom", robots as one of the important ring gradually get the approval of the Chinese government, for industrial applications of the research, the test of active compliance assembly based on the fault-tolerant parallel six-aix force sensor is conducted, the analysis and research of robot communication, assembly strategy, assembly algorithm, and the result of assembly are also conducted, the main contents of the paper are as follows:First of all, the research present situation of compliance assembly and six-aix force sensor are summarized briefly, the research present situation of fault-tolerant robots and fault-tolerant measurement technology are also introduced, respectively, through the modeling analysis of the force condition in the process of peg-in-hole assembly, the decoupling force information of the end of workpiece is obtained, which enhances the accuracy of force information, and the force feedback assembly algorithm is constructed by the force information. The monitoring index of force and moment for judging the assembly stage is obtained, and the assembly strategy is also developed.Secondly, the fault-tolerant control assembly platform is built, the auxiliary supporting parts are also designed and manufactured, the parameters and control system of the robot are illustrated, the robot’s calibration method and the connecting communication of C/S between computer and robot are explained detailedly, and the RAPID languages and program used of the robot are also explained, the robot control program for the experiment is written, the offline model of assembly process is proposed in the Robotstudio software, In addition, the transformation matrixs of robot’s each joint are calculated, which lays the foundation for trajectory planning.Furthermore, the information of fault-tolerant parallel six-aix force sensor is illustrated detailedly, the full range calibration is conducted with the data acquisition equipment which signals output in the form of strain, the calibration matrix and the error matrix is also obtained. The calibration algorithms of the sensor normal and fault are proposed, and the performance index of the sensor is also obtained. The relationship between generalized force and the voltage of each branch, between strain and calibration matrix are explained, and the theory of obtaining six-aix force is also explained, which lay the the foundation for compiling the information processing module of the fault-tolerant control software.Finally, the data acquisition equipments is introduced, and the robot control system integrated with the modules of information collection, information processing, information communications, and movement control is conducted, the fault-tolerant compliance control software is compiled with C++. The tests of peg-in-hole and spline assembly are completed through combing the assembly strategy and control algorithm, and the results are analysed and discussed detailedly, also lay the the foundation for the long shaft assembly in the industry.