Research Of Key Technology Of Industrial Robots On EPLC

Cartesian coordinate robot as an important branch of industrial robot has characteristicsof high precision, strong load, long life.It is widely used in welding, cutting, dispensing,handling, semiconductor processing, etc. Industrial technology research mainly concentratedin the trajectory planning of the robot, kinematics analysis, error compensation. At present,the cartesian coordinates robot controller has three forms: motion controller based on singlechip microprocessor, motion control card based on PC and motion control module based onPLC. This paper puts forward a kind of control system based on ePLC and mature CADtechnology, realizing the robot control. Paper trys introducing mature CAD technology toePLC development mode, the development of the code and parameter adjustment spun offfrom the ladder diagram function block development, but ompleted in the CAD.ePLC adoptsmodular design,which is extensible and scalable.File format of CAD software is diversiform,subject chooses PLT as trajectory carrier file.Subjects uses three software platform.AutoCAD completes trajectory planning.CASSladder diagram development platform completes the development of function blockapplication.HPGL program compiler completes task which the PLT file compiled into objectfiles.HPGL compiler has functions of edit, compile, download.The hardware adopts ePLC ofCASS-EPLC70A.Introducing HPGL in the ePLC needs to finish works of3parts: interfacedesign, thread and driven design.1)Interface design includes three parts: compile, memory allocation, and programdownload.Compile refers to convert HPGL program to the target file.Memory allocationincludes FLASH allocation and ARM allocation, achieving coordination among HPGLprogram, ladder diagram and the engine, ensuring data security. Program’s download isdivided into debug and release mode.2)Thread allocation,according to characteristics of tertiary thread preemptive schedulingalgorithm,configure different level thread of function block application, HPGL programexecution control algorithm and urgent task.3)Driven design including HPGL instruction table structure design, function blockprogramming, HPGL program execution control algorithm design. The feasibility of theproject is verified on the gantry cartesian coordinates robotic.analysis the execution results ofStraight line, rectangle, circle and helix, and the irregular track.Experiment has some problems which need to be improved, but every execution trace will fits in the CAD drawing track, which verifies the feasibility of the subject.