ABSTRACT
Building a precision machine has always been a very expensive and time-consuming job. This chapter describes two very important principles: the error correction of a measuring machine and multiple redundancy and statistical analysis of measurement algorithms. At NBS, John Simpson, the Director of the Center for Manufacturing Engineering, was a rather philosophical scientist, an early and enthusiastic believer in the idea of deterministic metrology. Under his guidance, NBS decided to implement these ideas on a three-dimensional coordinate measuring machine (CMM). The implementation of error mapping CMMs and machine tools changed the design criteria of the machines in a very important way. One of the earliest critical decisions was which CMM to use as a test bed. The chapter discusses the view of measurements as a "production process with a product, numbers, whose quality may be controlled by the methods of statistical sampling.".
