摘要
设计了一种DSP+PLC架构的焊缝激光跟踪系统,采用DM642芯片作为图像处理引擎,以西门子S7-200作为系统的主控单元和伺服电机的控制驱动单元,简化了跟踪系统的复杂性。通过PLC主控命令设置焊接参数,能使跟踪系统适应不同焊接工艺的需要。DSP与PLC采用工业标准的MODBUS协议的RS485串行通信,采用最高波特率进行通信,减少了数据传输时间和PLC的MODBUS响应时间。采用了一种快速有效的图像二值化阈值的提取方法,并利用图像二值化处理进行初步滤波,再通过针对高亮度像素的选择性中值滤波,急剧减少了图像滤波的计算量,降低了中值滤波时间。并设计了针对中厚板件焊接的图像处理优化方法,用粗略的投影算法逐步提取出焊缝的关键区域,能减少图像处理区域面积,为进行更加详细的焊缝特征点提取算法节约了处理时间,促进了焊缝跟踪系统的实时性响应。
This article reported a weld seam laser tracking system with DSP and PLC for medium and thick plate. The DM642 chip is as the image processing engine and the Siemens S7-200 as the control and servo motor drive units. The weld seam tracking parameters are fixed by the PLC ,so the weld seam tracking system can adapt to the needs of different welding processes. The communication style between DSP and PLC is RS485 and bases on MODBUS serial communication protocol that is one of the industry standards in communication. At the highest baud rate,the data transmission time and the PLC MODBUS communication response time is least. Using a fast and efficient image threshold extraction method can drastically reduced the amount of calculation of the image filtering.
出处
《电焊机》
北大核心
2013年第6期88-94,共7页
Electric Welding Machine
