Design And Application Research Of SCARA Robot Motion Controller

The plane articulated assembly robot (SCARA) applies the most widespread one kind of robot, both may use in actually to produce, and may use in the teaching experiment and the scientific research. Uses in actually to produce, it can satisfy the assembly work content change frequent request; Uses in the teaching experiment, it can make the person direct-viewing to understand the robot structure composition, the motion principle and so on, therefore develops SCARA to have the widespread practical significance and the application prospect. The robot control technology finely is playing to its performance the significant role. In order to enhance stable, reliable and the industry scene anti-jamming, use "PC + motion controller" the structure realizes the robot control: In the servo system the servo level computer uses take the Digital Signal Processing (DSP) as the core multiple spindle movement controller, with the aid of the DSP high speed signal processing ability and the operation ability, may simultaneously control the multiple spindle movement, realizes the complex control algorithm and obtains the fine servo performance."The PC +motion controller" the control robot technology research has become the automated domain the hot spot, and obtained a bigger development. In "PC + motion controller" in the robot control mode, the motion controller affects one of robot performance key components, it is affecting the robot development in the certain degree. At present, because the artificial intelligence, the computer science, the sensor technology and other correlation disciplines making great strides, cause the robot the research to carry on in the high level, the traditional movement controller as a result of its own enclosed structure, already could not satisfy the modern industry and society's demand. Simultaneously because robot assembly system because does not have the uncertainty, not completeness, Close coupling,and so on many questions, sometimes also very is difficult to obtain the precise number, therefore to controls the algorithm to have the very high request.As a result of the DSP component high performance, each DSP merchant unceasingly promotes in view of the motion control chip base on DSP, enables DSP to become the complex motion control system and in the high performance movement controller first choice component. TMS320LF2812 components are American TI Corporation develop the low cost, the high performance DSP component which controls face the electrical machinery, its instruction cycle only has 33ns, may satisfy the system well the timely request, can realize the complex control algorithm. Therefore, has developed four axes robots intelligence motion controller by DSP as the core, has designed based on the DSP SCARA motion controller, has all made the detailed construction to its software and hardware design. As the core motion controller can complete the majority of real-time controls function and the plurality of controls algorithm base on DSP, displayed the DSP operation function to be strong, the timely good merit, TMS2812 not only may satisfy us in the operation performance aspect need, moreover because its programmability, caused us to be allowed to obtain the system design in a hardware level the enormous flexibility.Along with the electronic technology and the computer science development, enables the people more and more to take to develop each kind take the integrity robot dynamics model as the foundation dynamic control plan, take fully displays as the robot mechanism potential. This article research based on dynamics model robot control plan. This article uses two steps Lagrange equation to establish the SCARA robot dynamics model.This article introduces fuzzy control the introduction in servo control system, the fuzzy control will not rely on the object precise model, will be able to overcome the robot dynamics model Central Africa linearity well, when will change influence, but also has the stable state precision not high shortcoming, will blur for this this article controls and the traditional PID control unifies increases its stable state precision. In the fuzzy PID control algorithm, difficulty is the PID three parameters universes of discourse determination, this article first using the Ziegler-Nichols method determined the PID universe of discourse the starting value, then through the experiment determined the parameter the universe of discourse, the simulation experiment result indicated, uses the fuzzy PID controller the system to move, the static performance surpasses traditional PID and the common fuzzy controller, also has a stronger robustness regarding the system parameter change.This article refers to the many kinds of kinematics modelling method, achieves the goal according to the SCARA robot characteristic and the request, the consideration fingernail did not reciprocate omni-directional revolves the terminal with the hand fingernail which causes in the spatial scope the position posture change, Only considered to the big and small arm the position variation which Revolves in the plane,this topic used is divided the joint modelling the method to establish the SCARA robot kinematics model and to carry on Solution to the inverse kinematics of robot, The SCARA robot control system uses the double speed control strategy and two kind of different paths plans algorithm, on the position control used inserted based on the rectangular coordinates space linearity makes up the algorithm, but the lower position control used based on the joint space straight line linear interpolation algorithm.In order to satisfy on the position machine to the computing time and the lower position machine to the high speed control request, as well as carries on the plurality of controls algorithm for the enhancement control system the ability, the application high performance DSP design movement controller, and the control mode builds an general robot by "PC + motion controller" to test the platform, proposed the double speed control strategy. On the position machine uses general PC machine, is responsible for the system administration, the man-machine alternately, the kinematics equation solves, the path plan and so on, by lower frequency to lower position machine transmission instruction and data. The lower position machine by based on the DSP motion controller, the servo driver, the exchange servo motor and the photoelectricity encoder is composed. Takes the position feedback by the incremental encoder signal. The motion control-card through fourth harmonic ganeration multiplications, the addition and subtraction counter obtains the actual position. The physical location information has in the location register, the computer may through control the register to carry on reads. The motion controller target location, obtains by the computer through the robot path planning. Obtains the position error value through the internal computation, after again the process adds and subtracts the fast control and the digital filter, the operational amplifier, the pule-width modulation, the hardware processing electric circuit, after the transformation outputs the servo motor the PWM control signal. Each joint may complete the independent servo-control.According to design goal which draws up, we carried on work and so on hardware design, software design, software simulation, hardware simulation, the experiment had proven this plan hardware design reasonable, the software function was perfect, for carried on the thorough robot kinematics algorithm, dynamics analysis, nonlinear system decouple, the robust principle analysis and so on the advanced control algorithm research has provided the very good experimental platform.