897 research outputs found
Geometrico-Static Analysis of Under-Constrained Cable-Driven Parallel Robots
No full textThis paper studies the kinematics and statics of cable-driven parallel robots with less than six cables, in crane configuration. A geometrico-static model is provided, together with a general procedure aimed at effectively solving, in analytical form, the inverse and direct position problems. The stability of equilibrium is assessed within the framework of a constrained optimization problem, for which a purely algebraic formulation is provided. A spatial robot with three cables is studied as an application example
Stability Analysis of Underconstrained Cable-Driven Parallel Robots
No full textThis paper studies cable-driven parallel robots with less than six cables, in crane configuration. A geometrico-static model is provided, and the stability of static equilibrium is assessed within the framework of a constrained optimization problem. The method relies on ordinary linear-algebra routines, and it may be very simply applied to the most general architectures. Several examples are provided, concerning robots with a number of cables that range from 2 to 4
Direct Geometrico-Static Problem of Under-Constrained Cable-Driven Parallel Robots with Three Cables
No full textThis paper studies under-constrained cable-driven parallel robots with three cables. A major challenge in the study of these manipulators is the intrinsic coupling between kinematics and statics, which must be tackled simultaneously.
In this contribution, a general elimination procedure is provided that solves the direct geometrico-static problem, which consists in determining the platform posture and the cable tensions when the cable lengths are assigned. The problem is proven to have up to 156 complex solutions
Inverse geometrico-static problem of under-constrained cable-driven parallel robots with three cables
No full textThis paper studies under-constrained cable-driven parallel robots with three cables. A major challenge in the study of these manipulators is the intrinsic coupling between kinematics and statics, which must be tackled simultaneously. In this contribution, general elimination procedures are provided that solve the inverse geometrico-static problem with assigned orientation or position. In the former case, the platform orientation is given, whereas the platform position and the cable lengths and tensions must be computed. In the latter case, the platform position is known, whereas the platform orientation and the cable lengths and tensions must be calculated. These problems are proven to admit up to 1 and 24 real solutions, respectively
Leave 2nd generation behind: cost effective solutions for small-to-large scale DH networks
No full textMERLET (G.)
No full textDubois Patrick. MERLET (G.). In: Le dictionnaire de pédagogie et d'instruction primaire de Ferdinand Buisson : répertoire biographique des auteurs. Paris : Institut national de recherche pédagogique, 2002. p. 107. (Bibliothèque de l'Histoire de l'Education, 17
Jean-François Merlet. Jeunesse et liberté d’association
No full textJean-François Merlet. Jeunesse et liberté d’association . In: Agora débats/jeunesses, 27, 2002. Les jeunes et le risque. p. 164
Ségolène MERLET
No full textSégolène Merlet est conseillère pédagogique détachée auprès de l’agence de l’enseignement français à l’étranger (AEFE) en poste à Washington, États-Unis. Adjointe de l’IEN, elle accompagne les 29 établissements de la côte Est des États-Unis et du Canada homologués par le ministère de l’éducation nationale (MENJS) sur toutes les questions et problématiques pédagogiques du 1er degré. Formatrice et gestionnaire M@gistère, elle conçoit et anime des stages de formation continue à l’attention des p..
Automatic self-calibration of suspended under-actuated cable-driven parallel robot using incremental measurements
No full textThis paper focuses on the problem of the initial-pose estimation by means of proprioceptive sensors (self-calibration) of suspended under-actuated Cable-Driven Parallel Robots (CDPRs). For this class of manipulators, the initial pose estimation cannot be carried out by means of forward kinematics only, but mechanical equilibrium conditions must be considered as well. In addition, forward kinematics solution is based on cable-length measurements, but if the robot is equipped with incremental sensors cables’ initial values are unknown. In this paper, the self-calibration problem is formulated as a non-linear least square optimization problem (NLLS), based on the direct geometricostatic problem, where only incremental measurements on cable lengths and on swivel pulley angles are required. In addition, a data acquisition algorithm and an initial value selection procedure for the NLLS are proposed, aiming at automatizing the self-calibration procedure. Simulations and experimental results on a 3-cable 6-degree-of-freedom robot are provided so as to prove the effectiveness of the proposed methodology
- …
