Research On Position And Gesture Adjusting Of Plane Flexible Assembly System

As technologies such as automation, digitization and information technology are adopted in theplane components assembly, the assembly technology, which has been gradually changing toautomation, digitization and flexibility, is very different from the old times when traditionaltechnologies such as manual and rigid positioning were mainly used. Based on such a fact, a flexiblepositioning system used for plane components assembly, taking a kind of3-DOF parallel manipulatornamed Tripod as positioning unit, has been designed.Compared to serial manipulator, parallel manipulator, which now has been generally used inCNC machining, motion simulation, sensors, fine operation and other fields, has many advantageslike high rigidity, high precision, strong load capacity and so on. It’s obvious that such advantages ofparallel manipulator value much in the plane flexible positioning system as well.However，because of the high nonlinearity of parallel manipulator, its dynamic property is hardto be described with a precise mathematical model. To tackle with this problem, this paper studies itskinematics first and gets its reverse kinematics with a kind of rapid method called closed method.Based on this, a kind of control strategy, which doesn’t need precise model, using CMAC-PID(acontroller composed of Cerebellar Model Articulation Controller and PID controller) control method,is adopted to control one single Tripod. The trajectory plan of Tripod is also analyzed to get betterposition control result. The plane flexible positioning system is composed of3Tripods. Spherical pairwith vacuum cup is used to connect Tripod with the plane component.For the whole system’s requirement of real-time, a kind of method with less memory space andhigher computational efficiency named quaternion is used to describe the plane component positionand gesture transformation, which always takes up much time in the whole calculation. At the sametime, a kind of interpolation method called quaternion spherical linear interpolation is used to get theuniform rotation of plane component. Uniform rotation is important in the process of plane assembly.At last, simulations based on software Matlab/Simulink and Recurdyn is taken to verify theflexible positioning system and get good simulation results.