Control of a multi-degree of freedom worktool for vibrations assisted forging

Abstract

is an open access repository that collects the work of Arts et Métiers ParisTech researchers and makes it freely available over the web where possible. Abstract-This paper addresses the control of a tool developed to superimpose vibrations along several directions on a piece during forging. Piezoelectric actuators are used to provide the required forces and speeds. Due to the minute displacements of the actuators, flexible hinges are used in a special arrangement in order realize the specified movements and to ensure controllability. The experimental results confirm the approach.

Vector control applied to a Langevin transducer

“…And when the system is operated outside its resonance, it requires more voltage, thus leading to more dielectric losses. In forging processes, it is possible to control the vibration velocity in quasi-static state [2]. A Resonance Frequency Tracking System is introduced in [3] using digital circuits.…”

Modelling, identification and control of a Langevin transducer

“…The control described in [1] introduces two control methods to regulate only the vibration amplitude using PI and PID controllers for machining application. In forging processes, it is possible to control the vibration velocity in quasi-static state [2]. In [3] a resonance frequency tracking system is introduced using digital circuits, by direct measurement of the phase difference between the applied voltage and the input current, the transducer is controlled at the resonant frequency.…”