This short note points out an improvement on the robust stability analysis for electrically driven robots given in the paper. In the paper, the author presents a FAT-based direct adaptive control scheme for electrically driven robots in presence of nonlinearities associated with actuator input constraints. However, he offers not suitable stability analysis for the closed-loop system. In other w...

Robotic manipulators are highly nonlinear and coupled dynamic systems, which may be subject to different types of unknown disturbances such as joint frictions and end-effector external payloads. Such disturbances, when unaccounted for, cause poor tracking performance of the robot and may even destabilize the robot control system. In this paper we propose a novel nonlinear control scheme for rob...

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, a robust tracking control method for automatic take-off and trajectory tracking of a quadrotor helicopter is presented. the designed controller includes two parts: a position controller and an attitude controller. the attitude controller is designed by using the sliding mode control (smc) method to track the desired pitch and roll angles, which are the output of position controll...

A robust hybrid control method for robot manipulators is proposed which integrates an Ha controller and an adaptive controller. The Ha controller is used to minimize the effect of parameter uncertainties of the robot model on the tracking performance, while the adaptive controller continuously adjusts the model parameters to reduce the model error. Simulations show that disturbances generated f...

This short note points out an improvement on the robust stability analysis for electrically driven robots given in the paper. In the paper, the author presents a FAT-based direct adaptive control scheme for electrically driven robots in presence of nonlinearities associated with actuator input constraints. However, he offers not suitable stability analysis for the closed-loop system. In other w...

Mobile robot, especially wheeled mobile robot, with its simple mechanical structure and inherent agility, has attracted significant attentions for dynamic environment applications in the last two decades (Pin et al. 1994 and Purwin 2006). A general mobile robot Guidance, Navigation and Control (GNC) system is illustrated in the following figure. The main function of guidance system is to genera...

To overcome the disadvantages of conventional computed‐torque control and fuzzy control, and to exploit their attractive features, this paper proposes two types of adaptive control scheme combining conventional computed‐torque control and different fuzzy compensators for the robust tracking control of robotic manipulators with structured and unstructured unce...

A redundant robot has more degrees of freedom than what is needed to uniquely position the robot end-effector. In a usual robotic task, only the end-effector position tr'ajectory is specified. The joint position trajectory is unknown, and it must be selected from a self-motion manifold for a specified end-effector. In many situations the robot dynamic parameters such as link mass, inertia and j...

this paper presents a delay compensator fuzzy control for trajectory tracking of omni-directional mobile robots. fuzzy logic control (flc) of the robots is a suitable strategy for dealing with model uncertainties, nonlinearities and disturbances.  on the other hand, in many robotic applications such as mobile robots, delay phenomenon is able to substantially deteriorate the behavior of system's...