Showing papers by "Bernard Brogliato published in 1994"
TL;DR: The standard least-squares estimates of /spl theta//sub 2/* are modified using a hysteresis type switching algorithm that enables us to conclude on existence, uniqueness, boundedness and convergence of the solutions of the adaptive closed-loop system.
Abstract: This paper presents an adaptive control strategy for a class of first-order nonlinear systems of the form x/spl dot/=/spl theta//sub 1/*/sup T/f(x)+/spl theta//sub 2/*/sup T/g(x), where g(x) is a smooth function, whereas f(x) satisfies sectoricity conditions. /spl theta//sub 1/* and /spl theta//sub 2/* are constant parameter vectors. It is assumed that the system remains controllable for all values of x, but the sign of /spl theta//sub 2/*/sup T/g(x)(x) is unknown. The proposed adaptive scheme extends ideas previously presented the authors (1992) where the term premultiplying the input was supposed to be constant. The standard least-squares estimates of /spl theta//sub 2/* are modified using a hysteresis type switching algorithm that enables us to conclude on existence, uniqueness, boundedness and convergence of the solutions of the adaptive closed-loop system. >
38 citations
TL;DR: In this article, a direct adaptive impedance controller for force/position task is presented, assuming that the environment stiffness is unknown and considering the one-degree of freedom (dof) case.
11 citations
TL;DR: In this paper, the authors studied impact dynamics in view of control of manipulators subject to unilateral kinematic constraints during a complete robotic task with contact and non-contact phases, and the relationships between continuous-dynamics model that approximate the rigid case and the variational approach (Lagrange equations) are discussed.
6 citations
4 citations
14 Dec 1994
TL;DR: In this paper, the authors point out some problems related with stabilization of motion-controlled manipulators that come in contact with a compliant environment, in particular the sufficient conditions guaranteeing asymptotic convergence of the solutions towards the steady-state solution.
Abstract: The goal of this study is to point out some problems related with stabilization of motion-controlled manipulators that come in contact with a compliant environment, in particular the sufficient conditions guaranteeing asymptotic convergence of the solutions towards the steady-state solution. The authors restrict themselves to a simple PD motion controller, and to the case of a purely elastic environment. >
2 citations