A novel approach is proposed for the attitude stabilization and reorientation of an axi-symmetric spacecraft subject to two gas jet actuators. The approach is based on a new formulation of the attitude kinematics. Abstract| In this paper we consider the problem of attitude stabilization of an axi-symmetric spacecraft using two pairs of gas jet actuators. These actuators provide control torques ...

‎in this paper‎, ‎we study spectral element approximation for a constrained‎ ‎optimal control problem in one dimension‎. ‎the equivalent a posteriori error estimators are derived for‎ ‎the control‎, ‎the state and the adjoint state approximation‎. ‎such estimators can be used to‎ ‎construct adaptive spectral elements for the control problems.

robot en tareas de seguimiento.

We consider the high energy limit of the colour ordered one-loop five-gluon amplitude in the planar maximally supersymmetric N = 4 Yang-Mills theory in the multiRegge kinematics where all of the gluons are strongly ordered in rapidity. We apply the calculation of the one-loop pentagon in D = 6−2ǫ performed in a companion paper [1] to compute the one-loop five-gluon amplitude through to O(ǫ2). U...

Invariant methods for formulating and analying the mechanics of the skeleto-muscular system with geometric algebra are further developed and applied to reaching kinematics. This work is set in the context of a neurogeometry research program to develop a coherent mathematical theory of neural sensory-motor control systems.

Many human and animal tasks are thought to be controlled with the t informational variable. It is widely accepted that controlling the rate of change of t (tau) during decelerative tasks, such as when braking or landing, is one common perceptual control strategy. However, many tasks require accelerating before decelerating to a goal, such as reaching. An advancement of t theory shows how a sing...

We present a new framework for prioritized multi-task motion/force control of fully-actuated robots. This work is established on a careful review and comparison of the state of the art. Some control frameworks are not optimal, that is they do not find the optimal solution for the secondary tasks. Other frameworks are optimal, but they tackle the control problem at kinematic level, hence they ne...

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...