Dynamic Modeling of a 3-DOF Articulated Robotic Manipulator Based on Independent Joint Scheme

Abstract

Joint torque control of a robotic manipulator requires a close dynamic description model involving the non negligible dynamics of the subsystems making up the system. The mathematical model for joint torque control of the robotic manipulator has been identified as one of the major sources of failures of commercial robots. The manipulator is basically made up of links connected by joints, and the torque that moves the links connected to a joint is produced by the joint actuator and also in practice, the control law is fed into the actuator inputs, therefore the actuator dynamics becomes non negligible dynamics in the dynamic modeling of the manipulator for robust joint torque control. Hence, a complete dynamic model of the manipulator which involves the link dynamics plus actuator dynamics was proposed. This paper focuses on the modeling of a 3DOF articulated manipulator based on independent joint (decentralized) scheme and the determination of the viscous damping coefficient for the joint torque control model. The independent joint model provides closer mathematical description of the manipulator and also enhances robust controller design. Joint damping coefficient B, was determined through experiment based on bode plot of the open loop gain. From the results, it was concluded that joints I and II achieved the best performance when B is 0.001N.m/rad /sec and 0.01N.m/rad /sec respectively.

Robust Control for a 3DOF Articulated Robotic Manipulator Joint Torque under Uncertainties

“…In order to achieve a model to design the controller the dynamics of both the actuator and link are coupled at the gears using the independent joint scheme based on Single Input Single Output (SISO). The 3DOF robotic manipulator model is explained in details in [30]:…”

“…The influences of the nonlinearities, unmodeled and neglected dynamics in the model are treated as disturbances and the controller is designed to be robust against them [30].…”

“…Thus, it was concluded that the H-Infinity controller achieved better performance and stability robustness characteristics for the joint torque control than the PID. Agbaraji et al; JERR, 9(4): 1-13, 2019; Article no.JERR.53565 2…”

Modelling and Simulation of Fuzzy-based Coordination of Trajectory Planning and Obstacle Avoiding for RRP-Typed SCARA Robots

“…In the basic group of 3-DoF industrial robots, there are many different categories of kinematic structures including articulated manipulators [9], Spherical manipulators [10], SCARA manipulators [11], cylinder manipulators [12], cartesian manipulators [13]. Among these categories, RRP-typed SCARA robots have been strongly invested because of flexible trajectory planning solutions with rapidly exploring random algorithms.…”

Controlador adaptativo aplicado em um robô manipulador com três juntas de revolução

“…No projeto de um controlador para atividades de alta precisão, se faz necessário a obtenção de um modelo dinâmico preciso. Na literatura, existem várias abordagens para a modelagem desses sistemas, como em Al-Qahtani et al (2017), Agbaraji et al (2017), Liu and Liu (2016). Craig (2013) apresenta um procedimento para a obtenção de um modelo dinâmico do manipulador a partir do cálculo de um modelo cinemático dos parâmetros de Denavit-Hartenberg, das matrizes de rotação, dos vetores de posição e dos valores das acelerações lineares e angulares dos elos do manipulador.…”