Modeling and Control of a DC Motor Coupled to a Non-Rigid Joint

Abstract

Throughout this paper, the model, its parameter estimation and a controller for a solution using a DC motor with a gearbox worm, coupled to a non-rigid joint, will be presented. First, the modeling of a non-linear system based on a DC Motor with Worm Gearbox coupled to a non-rigid joint is presented. The full system was modeled based on the modeling of two sub-systems that compose it—a non-rigid joint configuration and the DC motor with the worm gearbox configuration. Despite the subsystems are interdependent, its modelling can be performed independently trough a carefully chosen set of experiments. Modeling accurately the system is crucial in order to simulate and know the expected performance. The estimation process and the proposed experimental setup are presented. This setup collects data from an absolute encoder, a load cell, voltage and current sensors. The data obtained from these sensors is presented and used to obtaining some physical parameters from both systems. Finally, through an optimization process, the remaining parameters are estimated, thus obtaining a realistic model of the complete system. Finally, the controller setup is presented and the results obtained are also presented.

Towards a More Robust Non-Rigid Robotic Joint

“…As can be seen from [22], the model presented is correct and can be applied to the modeling of a non-rigid joint. However, taking into account the non-linearity of the dead zone of the joint, it was decided to modify the presented model to predict this non-linearity by first changing Equation (3):…”

“…In this paper, the design process for the next generation of the already existent non-rigid joint will be introduced, upgrading some aspects that were missing or needed in the previous version [22]. One difference in the developed joint from the above-mentioned works is the fact that a damping component has been added, which is useful in reducing high frequency oscillations, combined with the fact that it has been developed with passive components and therefore does not require energy consumption for achieving non-rigidity.…”

Design, Modeling, and Control of a Single Leg for a Legged-Wheeled Locomotion System with Non-Rigid Joint

“…After some tests that were carried out and presented in previous publications (Ref. [17], preceded by Ref. [16]), it was found to be more convenient to use in-line gearboxes.…”

Design, Modeling, and Control of an Autonomous Legged-Wheeled Hybrid Robotic Vehicle with Non-Rigid Joints

“…As in the past [22], the generic model for a DC motor is used, since the motor-gearbox system is equivalent. Equation ( 1), rearranged to obtain Equation ( 2), are the main equations used to model the motor.…”

“…The performed hardware tests to estimate the mentioned parameters were detailed in [22]. Figures 13, 14, and 15 present the collected data, which allow the estimation of the motor model parameters.…”