This paper presents a discrete-time robust control for electrically driven robot manipulators in the task space. A novel discrete-time model-free control law is proposed by employing an adaptive fuzzy estimator for the compensation of the uncertainty including model uncertainty, external disturbances and discretization error. Parameters of the fuzzy estimator are adapted to minimize the estimat...

in this study, a novel variable impedance control for a lower-limb rehabilitation robotic system using voltage control strategy is presented. the majority of existing control approaches are based on control torque strategy, which require the knowledge of robot dynamics as well as dynamic of patients. this requires the controller to overcome complex problems such as uncertainties and nonlinearit...

In this paper, dynamic equations of motion of a 5 DoF robot manipulator including mechanical arms with revolute joints and their electrical actuators are considered. The application of integrator backstepping technique for trajectory tracking in presence of parameters of uncertainty and disturbance is studied. The advantage of this control technique is that it imposes the desired properties of ...

in order to determine the stability of underwater robots, their governing differential equations of motion in vertical and horizontal planes should be investigated. for horizontal plane stability, using routh stability criterion, four hydrodynamic coefficients, including derivatives of the lateral force and vertical moment with respect to sway and angular velocity are required. these coefficien...

Tracking control of the direct-drive robot manipulators in high-speed is a challenging problem. The Coriolis and centrifugal torques become dominant in the high-speed motion control. The dynamical model of the robotic system including the robot manipulator and actuators is highly nonlinear, heavily coupled, uncertain and computationally extensive in non-companion form. In order to overcome thes...

Quadruped robots have unique capabilities for motion over uneven natural environments. This article presents a stable gait for a quadruped robot in such motions and discusses the inverse-dynamics control scheme to follow the planned gait. First, an explicit dynamics model will be developed using a novel constraint elimination method for an 18-DOF quadruped robot. Thereafter, an inverse-dynamics...

a mobile manipulator robot is known as a complex system due to some properties such as coupling between the manipulator and mobile chassis, holonomic and nonholonomic constraints, multivariable and nonlinear dynamics. the control of robot faces the external disturbance, parametric uncertainty and unmodeled dynamics. therefore, the use of an adaptive fuzzy system is suggested for its capability ...

This paper presents a novel robust fractional PIλ controller design for flexible joint electrically driven robots. Because of using voltage control strategy, the proposed approach is free of problems arising from torque control strategy in the design and implementation. In fact, the motor's current includes the effects of nonlinearities and coupling in the robot manipulator. Therefore, cancella...

This paper presents a robust fractional order controller for flexible-joint electrically driven robots under imperfect transformation of control space. The proposed approach is free from manipulator dynamics, thus free from problems associated with torque control strategy in the design and implementation. As a result, the proposed controller is simple, fast response and superior to the torque c...