The cutting edges of a grinding wheel are geometrically undefined in locatoins and shapes. As a result, generalisation or estimations of the grinding wheel surface condition are difficult to make with any degree of accuracy. Therefore, It is necessary to develop techniques for examining details of the grinding wheel topography in order to ascertain quantitative measurements of cutting edges. This paper describes the sensitivity, accuracy, working range and other statistical parameters for the highly accurate novel sensor that detects in-process changes of the ginding wheel topography. The sensor based on measuring static pressure variations in an impinging jet of air on a surface by a miniature high frequency transducer. Experimental work was carried out to ensure the benefits of this sensor. The sensor was calibeated using standards surface roughness specimens. The sensor can be used for measuring accurate distances, shafts or cams run out, form errors, as well as surface roughness and surface structure.