This paper studies the modeling and analysis of a system with two cooperative manipulators working together on a common task. The task is defined as the transportation of an object in space. The cooperative system is the dual-arm of the humanoid robot Nao, where the serial architecture of each arm has 5 degrees of freedom. The kinematics representing the closed chain system is studied. The mobility of the closed-loop system is analyzed and the nature of the possible motions explored. The stiffness of some motors can be reduced until they behave as passive joints. Certain joints are then chosen as actuated (independent) and the others as passive (dependent). The serial and parallel singular configurations of the system are considered. From the kinematic analysis, admissible and inadmissible minimum actuation schemes are analyzed. Furthermore the dynamic performance of the schemes is compared to find the optimum minimum actuation scheme.

FIFTH IFAC SYMPOSIUM ON ROBOTS CONTROL SYROCO '97 (3–5 SEPTEMBER 1997)

SYROCO '97 was the fifth of the IFAC series of triennial Symposia on Robot Control. Previous events were held in Barcelona (Spain), 1985; Karlsruhe (Germany), 1988; Vienna (Austria), 1991 and Capri (Italy), 1994. SYROCO '97 was held from September 3 to 5, 1997 in the “Cité des Congrès” in Nantes, France. The Chairman of the International Programme Committee was Bernard ESPIAU from INRIA Rhône Alpes (FRANCE); the Chairman of the National Organizing committee was Wisama KHALIL from IRCyN (Ecole Centrale de Nantes-FRANCE).

This paper presents the software package SYMORO+ for the automaticsymbolic modelling of robots. This package permits to generate the directgeometric model, the inverse geometric model, the direct kinematic model, theinverse kinematic model, the dynamic model, and the inertial parametersidentification models.

The structure of the robots can be serial, treestructure or containing closed loops. The package runs on Sun stations and PCcomputers, it has been developed under MATHEMATICA and Clanguage. In this paper we give an overview of the algorithms used in thedifferent models; the computational cost of the dynamic models of the PUMArobot are given.