Study On The Laser Scanning Seam Tracking Sensor

The automatic welding robot technology is one of the most important research fields of modern welding technology. In automatic welding, detection and conduction is security of the quality of welding. Therefore, welding seam tracking sensor technology is the precondition of the implementation of robot welding automatically. In this paper, after analyzing both domestic and overseas research conditions of welding seam identification and tracking technology, as well as contrasting different types of seam tracking sensor, a laser scanning seam tracking sensor is designed, which is based on Laser triangulation and Rotating mirror scanning technology, and uses a linear CCD as the reception device of light-spot.The laser scanning seam tracking sensor uses a infrared spotted laser as light source, after scanning work piece point-to-point by the Rotating mirror scanning system, finally forms image on the linear CCD. The light path of welding tracking sensor is designed based on straight triangulation, and the parameter of light path is certified based on distinguish ability of the system and measuring range. Thus a Rotating mirror scanning system which meets the sensor system requirement is designed.Based on analysis of the basic structure of CCD, as well as work principle and sequential logic of driving pulse, driving circuit of linear CCD based on complicated CPLD is designed. According to the character of CCD analog output signal, high-powered amplified filter circuit and A/D switching circuit for the usage of digitizing of CCD output signals is reallized.The experiment device of laser scanning welding tracking sensor is designed, manufactured, and debugged. Mechanical structure of each part is designed, and linear CCD hardware circuit board is manufactured as well. Thronging the measuring experiment, image data acquisition and upload is reallized. The experiment result certified the design principle, and requirement for next work is also presented.