Research On The Method Of Coordinate Unification Of Composite Multi-sensor Coordinate Measuring Machine

Measurement requirements tend to be higher in aerospace,precise manufacturing and dissemination of value of quantity,including higher measurement accuracy and higher measurement efficiency,which results in higher measurement technology.Traditional contact measurement has good adaptability,high precision but slow speed.Non-contact measurement has high speed,efficiency and miniaturization features,but it is easy to be limited by the shape of the workpiece and other factors,making it difficult to achieve measurement of all parameters.Thus,a single probe can not be unable to meet all requirements of measurement in many cases,which leads to greater demand for high-precision composite measurement of contact and non-contact measurement and more and more requirements: more functions,high flexibility and high precision.Our research group from Tian Jin University supported by a project of national major scientific instruments and equipment development--development and application of high-precision complex coordinate measuring machine launches an in-depth research on multi-sensor data fusion and cooperative measurement.The coordinate unification of high-precision complex coordinate measuring machine is mainly studied in this paper,which lays a good foundation for data fusion.In this paper,the research is first based on the existing OGP ZIP-250 as an experimental platform for research of methods and the spatial geometric relationships of its touch probe and image sensor can be obtained by data acquisition and data processing of measured objects so as to pave the way for coordinate unification of developed sample machine.Then we validate the methods of coordinate unification and come to conclusion and prospect by using the developed sample machine as an experimental platform in the paper.The primary works of this paper can be summarized as follows:(1)Introducing structure design of composite multi-sensor coordinate measuring machine.Including selection,operational principle and measuring characteristics of three sensors--touch probe,image sensor and chromatic confocal.Then proposing the independent calibration of each sensor to correct inherent error of them.(2)Proposing a method of coordinate unification in two dimensions by angle gauge blocks.Comparing a standard ball with an angle gauge block as a standardartifact and analyzing the deficiency of a standard ball in this specific occasion.And validating the effectiveness and convenience of an angle gauge block by measuring separately tactile probe and image sensor of OGP ZIP-250.(3)Proposing a method of coordinate unification of touch probe,image sensor and chromatic confocal in three dimensions based on a geometry-combined standard artifact.Introducing the structure of it and analyzing its measurement methods and feasibility.At last,confirming its reliability and applicability by conducting experiments via the developed sample machine.The relevant sample machine of this project is the first developed machine which will reach the international advanced level of composite measurement.it can complete all kinds of high-end and complex measurement tasks.In this paper,we successfully realize the coordinate unification of three sensors in sample machine which is the prerequisite of data fusion and cooperative measurement,and is also the key to the development of sample machine.