Nowadays it is eagerly expected that, on one hand the environmental impact of agricultural activities is decreasing, and on the other hand the level of production is increasing in order to match the consumption demand of the growing worldwide population. To meet these opposite expectations, new production tools have to be developed. Recent advances in offroad mobile robotics may bring to promis...

in this article a new and an accurate method for kinematic and dynamic analysis of a parallel robot 3prs and a hybrid robot (parallel and serial) 3prs-rrp are presented, which is based on the denavit-hartenberg transformation matrix algebra. first, basic properties of various kinds of robots are compared, and then the denavit-hartenberg parameters and their table are introduced. next, the metho...

In this paper the problem of free gait generation and adaptability with reinforcement learning are addressed for a six-legged robot. Using the developed free gait generation algorithm the robot maintains to generate stable gaits according to the commanded velocity. The reinforcement learning scheme incorporated into the free gait generation makes the robot choose more stable states and develop ...

This research presents a dynamic level control algorithm to meet simultaneously multiple desired tasks based on their allocated priorities for redundant robotic systems. It is shown that this algorithm can be treated as a general framework to achieve control over the whole body of the robot. The control law is an extension of the well-known acceleration based control to redundant robots, and co...

The focus of this work is a study of the passive dynamic walking of a kneeless biped robot with torso on inclined slopes. We show that under a simple PD control applied between the torso and the stance leg the biped robot converges at a stable gait cycle. we present recent results of trajectory sensitivity analysis to effeciently determine the stability of limit cycles for the biped robot.

This paper focuses on the motion control problem of an omnidirectional mobile robot. A new control method based on the inverse input-output linearized kinematic model is proposed. As the actuator saturation and actuator dynamics have important impacts on the robot performance, this control law takes into account these two aspects and guarantees the stability of the closed-loop control system. R...

For the present paper, we developed an output feedback chattering position regulator for n-degreesof-freedom (DOF) robot manipulators with elastic and frictional joints. A stability analysis of the closed-loop dynamic system in question was developed within the framework of Lyapunov functions. Performance issues related to the chattering regulator are illustrated in numerical simulations and ex...

In this paper, we study a simple passive dynamic biped robot with point feet and legs without knee. The mathematical model describing the robot is a switched system, which includes an inverted double pendulum. Robot’s gait and its stability depend on parameters such as the slope of the ramp, mass distribution for the robot, and the length of its legs. The main result of the paper is an asymptot...

This paper considers the problem of output feedback trajectory tracking with a unicycle mobile robot system. A state-feedback controller for the non-linear error dynamics of the robot is combined with an observer that estimates the orientation error based on available trajectory information and measurement of the position coordinates. A stability analysis, derivation and implementation of the r...

In this letter, a model based disturbance attenuator (MBDA) for robot manipulators is proposed and the stability of the MBDA in robot positioning problems is proved via Liapunov’s direct method. This method does not require an accurate model of a robot manipulator and takes care of disturbances or modelling errors so that the plant output remains relatively unaffected by them. The output error ...