Research On Line Laser 3D Measurement System For PDC Bit Inspection

Industrial robot-based 3D measurement system is a kind of automatic measurement equipment that can replace humans.Highly automated equipment is the development direction of the future 3D measurement field.The thesis studies a system that can be used to realize the automatic measurement of PDC drills.This system is mainly composed of line laser vision measurement sensor and industrial robots.It has the advantages of high degree of automation,flexibility and non-contact measurement.Based on the actual requirements of the project,this paper designs a relay synchronizer,host computer software,synchronizer software,and supporting robot programs.Based on this,the hand-eye calibration algorithm and the point cloud filtering algorithm are mainly studied.The main content of the paper is as follows:(1)Build a transit synchronization platform: the data transmission hub of the measurement system,which completes data synchronization collection,storage,backhaul and industrial robot motion control.Its hardware uses Exynos4412 as the main control chip.The communication between the measurement sensor and the transit synchronization platform uses USB.The PC,relay synchronization platform and industrial robot communicate through TCP/IP protocol.The software uses the Linux operating system and supports multi-tasking to provide a better software platform for subsequent product upgrades.This paper proposes to use a synchronous pulse to coordinate the probe and the industrial robot to work synchronously.(2)The upper computer software is designed: This research has written host computer software for the PDC drill measurement and repair project.It completes the sensor's original data reception,filtering,and coordinate transformation,and realizes the introduction of planning coordinate control robot movement and step control robot movement.(3)Optimized hand-eye algorithm and point cloud algorithm: To solve the problem of transformation relationship between line laser sensor and industrial robot,the hand-eye calibration algorithm was optimized.The pass-through filtering algorithm is optimized,and the k-value is added to determine the filtering efficiency.(4)Complete the experimental test: The feasibility of the filtering algorithm was verified in the experiment,the influence of the intersection of the laser plane of scanning probe and the calibration sphere on the measurement results was analyzed,and a discriminant formula was further given to obtain a reasonable data during the calibration process.It is verified through testing that the measurement scheme of the line laser 3D measurement system is feasible.The measurement accuracy of the system can meet the measurement requirements of PDC drills and can be used in situations where the general accuracy requirements are not too high.It can provide certain ideas for the development of automatic measurement equipment.