Research On Application Specific Multi-axis Motion Control Chip Based On FPGA

Along with our country industrialization overall level unceasing enhancement, motioncontrol technology more and more dash forward show its important status and role, even inthe core technology status in some areas and industries. Motion control technology is the keyto promote the new industrial revolution, and can greatly improve the degree of automationand manufacture of flexibility, its unique role has itself made great development in recentyears, motion control industry will enter the rapid growth stage.Judging from the situation of motion control technology development in the domesticand overseas, this paper has analyzed our country of deficiencies in the fields and the gapbetween the developed countries in the industry. At present, there are many powerful motioncontrol chip in the domestic market, but most of these products are foreign, and this kind ofchip had circuit curing, there is function can’t be customized and reconstruction problemssuch as difficult to upgrade. In view of the above considerations, this topic propose to designof a application Specific multi-axis motion control chip such as the one with independentintellectual property rights,and the cost performance is much higher by FPGA’s features suchas powerful digital circuit design capability,and rich internal resources,and reconfigurabledesign. Around the key technology of motion control technology such as: speed control,interpolation technology,and position control, this topic mainly made a few aspects:(1) Analysis of domestic and international motion control technology development, andcompare several commonly used algorithms of motion control key technologies, finallychoosing digital differential analyzer（DDA）interpolation algorithm, trapezoidal or S curveacceleration and deceleration control,and incremental digital PID algorithm, etc., and putsforward the reasonable design and the hardware structure.(2) In this paper, the DDA linear and arc interpolation algorithm principle was furtherstudied，and a the DDA linear interpolation module and the DDA circular interpolationmodule in the FPGA to realize on the basis of this theory. To reduce error andhomogenization integrator overflow pulse, use the half load and shift left normalizedapproach; Use has achieved the DDA linear and circular interpolation module design acontinuous interpolation apparatus; In addition,bit pattern interpolation complement implementations was further studied, and the bit pattern interpolation module in the FPGA torealize.(3) In this paper, trapezoidal or S type curve acceleration and deceleration controlalgorithm principle was further studied，and on the basis of this theory a the acceleration anddeceleration controller of performance and functionality to meet the requirements in theFPGA to realize based on the idea of the state machine. This paper detailed introduces thehardware realization process. This topic design of acceleration and deceleration controlmodule through the corresponding data set can realize constant speed, linear acceleration anddeceleration, S curve acceleration and deceleration and emergency stop or decelerationcontrol functions.(4) Through comparative analysis of several kinds of PID control algorithm, taking intoaccount a lot of advanced PID control algorithm is more complex, difficult to implement inhardware, while the traditional PID control algorithm is simple, parameters tuning easyapplicability, high reliability characteristics, and ultimately choose to use traditionalincremental PID algorithm in the FPGA to realize. Further analysis and design of encoderfeedback signal processing module, and location management modules, these modules areused for the position control section.(5) Finally, the chip for pin distribution and internal register function managementdefinition, defined and the motion control chip based on FPGA internal some other functionmodules of the principle and method were introduced, the function module including steadyspeed function module, and interrupt management module. At last, debugging the motioncontroller using the chip to develop, and through the debugging phenomenon shows motioncontrol chip firmware driver of the subject design is reasonable,the IP core logic function iscorrect.