We present a control framework for achieving encirclement of a target moving in 3D using a multi-robot system. Three variations of a basic control strategy are proposed for different versions of the encirclement problem, and their effectiveness is formally established. An extension ensuring maintenance of a safe inter-robot distance is also discussed. The proposed framework is fully decentraliz...

Industrial robots are confronted with performing tasks where a contact with their environment occurs. Therefore, a need for control algorithms with position tracking performance and the force control ability appears. Up to date a lot of algorithms were proposed which deal with robot motion and force control. In this paper a robust impedance control law based on an attractive theory of sliding m...

Scientific robot competitions are considered a powerful drive for advancing the state-of-the-art in robotics research and development. This paper describes the research objectives and technical information of the SocRob@Home team who has been representing the Institute for Systems and Robotics (ISR) from the Instituto Superior Técnico since 1998 in different robot competitions. This paper discu...

Goal. The goal of this laboratory is to evolve a neural controller for a simple differential wheel drive cart robot (similar to the e-puck) that has to navigate in an environment as fast as possible while avoiding obstacles (for example, walls). Evolution is performed in the RoboGen Evolutionary Robotics platform, and tests of the best controller found by evolution can be done either in simulat...

An obstacle avoidance approach is introduced that has dynamic active regions. The dynamic regions are adapted to the current speed of the robot and there are different active regions used, one for speed reduction and one of turning away from obstacles. The overall strategy of this approach is that the robot can drive with high speed which will be reduced in front of an obstacle in order to do a...

This paper addresses the dynamics and control of di rect drive robots with positive joint torque feedback We analytically derive the system dynamics in closed form Even though it is coupled and nonlinear in gen eral it is substantially simpler than the robot link dy namics We also derive conditions on the robot con g uration which result in linear dynamics Motion con trol laws for both cases ar...

A nonlinear feedback path controller for a differential drive mobile robot is presented in this paper. First, a kinematic model in error coordinates expressed in a moving reference frame partially linked to the robot is developed. The control law is designed using backstepping method yielding exponential stability of the closed-loop system. Stability analysis is performed via Lyapunov stability...

Robots are currently helping humans by performing complex, repetitive, unpleasant and/or dangerous tasks in all kinds of environments. In order to progressively develop more complex tasks, it is usually necessary that these robots are able to navigate in dynamic and potentially unstructured environments. Although many navigation schemes for autonomous mobile agents have been proposed to solve t...