Title :
Admittance control of a human centered 3 DOF robotic arm using Differential Elastic Actuators
Author :
Legault, M.-A. ; Lavoie, M.-A. ; Cabana, F. ; Jacob-Goudreau, Ph ; Létourneau, D. ; Michaud, F. ; Lauria, M.
Author_Institution :
Dept. of Electr. Eng. & Comput. Eng., Univ. de Sherbrooke, Sherbrooke, QC
Abstract :
This video shows the functionalities of a 3 serial DOF robotic arm. Each DOF is actuated with a patent pending differential elastic actuator (DEA) [1,2]. Compared to the abundantly studied series elastic actuator [3,4], DEA uses a differential coupling between a high impedance mechanical speed source and a low impedance mechanical spring. Possible implementations of a mechanical differential include the use of a standard gearbox, harmonic drive, cycloidal gearbox, bar mechanism, cable mechanism and all other mechanism that implement a differential function between three mechanical ports. For the implementation reported in this video, we used a harmonic drive for a very compact design. A passive torsion spring (thus the name elastic), with a known impedance characteristic corresponding to the spring stiffness, is used, with an electrical DC brushless motor. A non-turning sensor connected in series with the spring measures the torque output of the actuator.
Keywords :
actuators; human-robot interaction; manipulator kinematics; actuator torque output measurement; admittance control; bar mechanism; cable mechanism; cycloidal gearbox; differential coupling; differential elastic actuators; differential function; electrical DC brushless motor; harmonic drive; high impedance mechanical speed source; human centered 3 DOF robotic arm; low impedance mechanical spring; mechanical differential; mechanical ports; nonturning sensor; passive torsion spring; serial robotic arm; spring stiffness; Actuators; Admittance; Impedance; Robot sensing systems; Robots; Springs; Trajectory;
Conference_Titel :
Intelligent Robots and Systems, 2008. IROS 2008. IEEE/RSJ International Conference on
Conference_Location :
Nice
Print_ISBN :
978-1-4244-2057-5
DOI :
10.1109/IROS.2008.4651039