一种基于DSP+FPGA的电子凸轮控制方法

摘要

Aiming at the requirements of integrating the electronic cam function into the DSP and FPGA-based controller card and reducing the burden of the DSP,an open-loop electronic cam control method based on the DSP and FPGA was presented.In this method,the discretion sub-range characterized by equal acceleration motion was used as the basic cam control element,and the assignment of the control system was functionally divided into the DSP and FPGA modules.The DSP as the master processor,was used to plan the trajectory of the electronic cam,send sub-range motion orders to the FPGA,inquire about the motion execution information about sub-ranges,and make the cam execution and other tasks of the control card well coordinated.The FPGA as the coprocessor,was used to fulfill the sub-range motion execution and related interface functions.In the FPGA's cam module,two cascaded DDA algorithm blocks were used for producing driving pulses.The simulation result shows that the frequency of the pulse train in the subrange changes smoothly,and the field application results indicate that the speed of the subrange changes smoothly,the speeds between two adjacent subranges are continuous,and the control system runs stably.%针对基于DSP+FPGA架构的控制卡中集成电子凸轮功能以及减轻DSP工作负担的需求,提出了一种基于DSP和FPGA的电子凸轮开环控制的方法.该方法以离散后的等加速度区间为凸轮运动控制的基本单元,并对DSP和FPGA进行了功能划分,将DSP作为主处理器,负责规划凸轮的运动规律,向FPGA发送各小区间上的运动命令并查询FPGA中电子凸轮模块对运动命令的执行情况,使凸轮运动与控制卡的其他任务相协调；将FPGA作为协处理器,负责实现小区间上的运动控制以及相关的接口功能.FPGA中的电子凸轮模块采用级联的两个DDA算法块生成进给脉冲.DDA算法的仿真实验结果表明,进给脉冲的频率变化平滑.现场应用结果表明,各个小区间内的运动速度变化平滑,相邻小区间的速度衔接是连续的,系统运行稳定可靠.