Robot Hand Held Teaching System Based On Single Light Spot And Attitude Sensor

Industrial robots are widely used in all walks of life.However,there are still some problems till now,such as difficult teaching and slow teaching.For this reason,it is proposed to design a robot hand-held teaching system based on binocular vision.The structure of hand-held teaching tool mainly includes attitude sensor and light-emitting point.The angle is measured directly by the attitude sensor to reduce the calculation of the posture of the hand-held teaching tool;a single light-emitting point is designed to obtain the position through binocular vision measurement,so as to reduce the interference of ambient light and reduce the difficulty of image processing.The main research contents include:(1)A robot hand-held teaching system based on single light spot and attitude sensor is designed The robot hand-held teaching system mainly includes binocular vision,hand-held teaching device and robot.Compare the binocular vision structure scheme and choose parallel binocular vision.Determine the distance between the two cameras by analyzing the relationship between the distance of the two cameras and the minimum accuracy,and then design the processing vision system integrated box.After analyzing and comparing the advantages and disadvantages of three kinds of hand-held teaching devices with different feature points,the hand-held teaching device with attitude sensor and single light spot is selected and processed.(2)Extract the pixel coordinates of light spot center.The light spot image is preprocessed,and four different image center point extraction algorithms are applied to obtain the light spot center pixel coordinates.A method to judge the stability of the four algorithms for spot center recognition is proposed.Set up an experimental platform to obtain a set of photos of light spots moving in a straight line and extract the pixel coordinates,then fit a straight line to it and calculate the residual sum of squares.The experimental results show that the binary core method works best.(3)Analyze the teaching principle of the hand-held teaching device and realize the teaching function of it.Derive the internal and external parameter model of the camera and obtain the parameters by Zhang Zhengyou calibration method.calibrate the hand-eye relationship of the robot by "two-step method",that is,the transformation relationship between the coordinate system of the robot end tool and the binocular vision system.A method for parameter calibration of the hand-held teaching device based on the least square method is proposed and the calibration is completed to improve the accuracy of teaching.Set up a hand-held teaching device teaching-robot reproduction experimental platform.Identify the center of the light spot by binary centroid method,and obtain the coordinates of the teaching point by hand-held teaching device.The robot end moves to the point to realize teaching reproduction.The results show that the maximum error of position reproduction is 2.5mm and the robot can complete the trajectory of straight line and arc through teaching points accurately.By using the hand-held teaching device,the teaching efficiency and ease of use of the robot have been greatly improved.