Seam Tracking Control Research Of Biaxial Robot Based On Double Structure Light Visual Sensing

With the application of welding technology development in many areas, such as:the manufacturing sector, field of powder metallurgy, automotive industry, electronicsindustry, biomedical fields, people are increasingly demanding high quality welding,welding work environments become more and more complex. Traditional controlmethods are difficult to achieve high accuracy seam tracking, so that the intelligentcontrol methods which have ability of self-control applied to seam tracking arenecessary.In the two-lane dual-axis robot structured light vision sensor seam trackingcontrol study, the first is to establish a two-axis robot control system hardwareplatforms, including dual-axis robots, controllers, computers, image acquisition card,data acquisition card, then establish communication relationships between devices.This paper presents a composite intelligent controller that adjusted estimatesfrom dual-mode controller, including the P-PID control method, Smith fuzzy PIDcontrol method, the threshold switching control strategy. A sensor according to theextracted control deviation by a control method and control strategy derived quantityof the controlled object (torch) is controlled to change its velocity. Dual-mode controlstrategy: When the deviation is larger using P-PID control, which can quick adjust thesystem; while deviation is small using Smith fuzzy PID control, Smith compensationprinciple input sensor can be improved by the system caused delays, fuzzy PIDcontrol used to achieve a small range correction, the design of the controller mustensure the stability and the interference of the welding process.By Matlab experiments, we can achieve dynamic system modeling, simulation,analysis, mimicking the actual work process seam tracking systems, advance systemsimulation and analysis to better understand the characteristics of the system. Byusing fuzzy PID controller, we could detect the input values e and ec in real-time.Based on fuzzy rules, we adjust parameters kp、ki、kd values online. The building offuzzy rules should consider the stability of the system, the response time, overshootand other factors. Controller software interface design is developed by VC language based on atwo-axis robot welds MISUMI of tracking control system. The software systemincludes image acquisition and processing, tracking controllers two parts, which isused to start of the welding system and tracking control of weld seam.Research under biaxial robot vision laser sensor wire straight, diagonal seamreal-time tracking experiment, the experiment has achieved relatively smooth weld.The error of weld seam between the real and the ideal condition is small, in thereal-time experiment welding torch has achieved high precision tracking. This provesthat the proposed controller is more reasonable.