Gear backlash is a quite serious problem in industrial robots, it causes vibrations and impairs the robot positioning accuracy. Backlash estimation allows targeted maintenance interventions, preserving robot performances and avoiding unforeseen equipment breakdowns. However, a direct measure of the backlash is hard to obtain, and dedicated auxiliary sensors are required for the measurement. This paper presents a method for estimating backlash in robotic joints that does not require the installation of extra devices. It only relies on data gathered from the motor encoder, which is always present in a robotic joint. The approach is based on the observation of a characteristic vibration pattern arising on the motor speed signal when backlash affects the joint transmission. By looking at the amplitude of this vibration some information about the entity of the backlash in the joint is gathered. Experimental results on simulated data are reported in the study to show the robustness of the method, also with respect of noise. Furthermore, tests on real-world data, gathered from robots installed in a production plant, demonstrate the efficacy of the technique. The approach is cost-effective, fast, and easily automatable, therefore convenient for the industrial world.


    Access

    Download


    Export, share and cite



    Title :

    A Virtual Sensor for Backlash in Robotic Manipulators



    Publication date :

    2022-01-01



    Type of media :

    Article (Journal)


    Type of material :

    Electronic Resource


    Language :

    English



    Classification :

    DDC:    629



    Virtual Measurement of the Backlash Gap in Industrial Manipulators

    GIOVANNITTI, ELIANA / Giovanni Squillero / Alberto Tonda | BASE | 2020

    Free access

    A sensor classification strategy for robotic manipulators

    Lima, Miguel / Machado, J. A. Tenreiro / Ferrolho, António | BASE | 2010

    Free access

    On the Redundant Drive Backlash Free Robotic Mechanisms

    Chang, Sun Lai | Online Contents | 1993



    SIRIAT: An Animation Module for Virtual Reality Simulation of Robotic Manipulators

    Cagetti, P. / Michelini, R. C. / Pampagnin, F. et al. | British Library Conference Proceedings | 1994