PRECISE ROBOTIC CHAMFERLESS PEG HOLE INSERTION OPERATION WITHOUT FORCE FEEDBACK AND REMOTE CENTER COMPLIANCE (RCC)

Robots can be widely used in the industrial assembly operation if the task can be performed with high precision, high speed and with low cos t. Peg-hole insertion is a fundamental operation whose problems have b een the focus of much work. In the passive accommodation solution, rem ote centre compliance (RCC) is used to perform chamfered peg-hole inse rtion. The principle exploited involves using RCC as a mechanical map which transfers the translational and angular errors, between the peg and the hole, into corrective motion. The potential advantages of mini mized cycle times are offset by the limited precision. This contrasts with techniques exploiting active accommodation which use a force sens or to arrive at the deviation, between the peg and hole axes, to achie ve chamferless insertion. A strategy is developed here that uses neith er of these additional accessories but instead exploits features of bo th techniques with defined initial conditions. The immediate advantage s of reduced hardware complexity are supplemented by evidence of trial s. These were based on a 31.99 mm diameter peg and a hole with a diame ter clearance of 0.02 mm. The results showed that the algorithm operat ed reliably with small clearances and with minimum cycle times. This c onfirms its potentially wide application in industry where its simplic ity can be fully exploited.