IN-PROCESS CONTROL OF SURFACE-ROUGHNESS DUE TO TOOL WEAR USING A NEW ULTRASONIC SYSTEM

This paper presents in-process monitoring and control of surface rough ness during machining processes via ultrasonic sensing. A newly develo ped system is utilized to measure the reflected intensity of ultrasoni c beams from the surface and in-process measurement capability is eval uated under machine vibration and tool wear. The experimental results show that the system is able to detect the changes in surface roughnes s caused by tool wear and can possibly be used to monitor tool wear. F inally, in-process control of surface roughness using the ultrasonic s ystem is demonstrated by adapting the system to a CNC machining center and performing geometric adaptive control. The results show it is pos sible to maintain surface roughness within 10% of the target value for tool wear up to 0.3 mm.