Objective
The research proposed will develop non-contact independent in-process measurement and inspection of machined parts whilst they are retained in the machine tool. The instrument will be a robot operated optical measurement system capable of comparing measurement data with specifications and tolerances. It will position at a series of accurately predetermined critical locations to give data as to the true dimensions of the component. Further uses exist in quality control and inspection of large fabrications. Programming will be developed to allow an integrated function in real time, with down time being reduced to a minimum. The control of sensor movement with the machine tool, plus the interaction of the sensor data with CAD data, will use simultaneous modelling and simulation to allow the integrated system to check for errors, clashes, path planning etc. Knowledge based programming will enable CAD comparisons giving updating of part programs to allow components to be finished within specification. The positioning coordinates are determined by an absolute length measuring interferometer which is swept and tilted through two axes. The geometric shape of the workpiece will be determined by projecting periodic patterns onto it. Digitised observed patterns produced by a line camera/camera array from the workpiece will allow computer processing, thereby giving unambiguous positional data; a technique that gives greater accuracy than state of the art triangulation methods. The overall system will be capable of measuring free form shapes to a minimum of 10 microns accuracy.