Control and measurement of clamping and machining forces in intelligent fixturing

Abstract

The thesis presents a novel force measurement technique in a fixturing arrangement with instrumented locators. The developed system aims to overcome the problems associated with the dynamometer and this study could lead to the feasibility of fixturing set-ups with instrumented locators as a viable alternative than a dynamometer. Attempt is also made to design a simple controllable electro-mechanical clamping element using the principle of direct torque control of a permanent magnet DC motor. The torque is controlled in the region of zero speed of the motor, which keeps wear and tear to a minimum. An optimisation method to determine the minimum optimal clamping force using linear programming is derived. This technique aims to simplify the process of optimisation and provide a methodology to find an estimate of the minimum clamping force through an iterative procedure so that control of clamping forces can be realised outside a laboratory environment.