Development of a Human Symbiotic Assist Arm “PAS-Arm” (Experimental System and Creation of Virtual Guiding Surfaces)
Mineo Higuchi* and Tsukasa Ogasawara**
*Advanced Technology R&D Center, Mitsubishi Electric Corporation, 8-1-1 Tsukaguchi-honmachi, Amagasaki, Hyogo 661-8661, Japan
**Graduate School of Information Science, Nara Institute of Science and Technology, 8916-5 Takayama-cho, Ikoma City, Nara 630-0192, Japan
We describe a new robotic assist device: the passive assist arm (PAS-Arm). PAS-Arms are intended for direct physical interaction with a human operator. PASArms are physically passive. The force to manipulate the arm end must be provided by the operator. Their purpose is not to enhance human strength, but to provide virtual guiding surfaces that constrain and guide the motion of the operator. PAS-Arms have three joints and a three dimensional workspace, but possess only two degrees of freedom due to the reduction of degrees of freedom created by a combination of Continuously Variable Transmissions (CVTs) and differential gears. In this paper, we first discuss the manipulability ellipsoid for the PAS-Arm. The major axis of the ellipsoid is the direction in which the arm end may be easily manipulated, and vice versa. We have developed an experimental system for the PAS-Arm. The CVTs of the experimental system may not adjust the transmission ratio to zero. Second, we describe an algorithm to address that problem. Finally, we present initial experiments that verify the PAS-Arm mechanism. The experimental results successfully produced virtual guiding surfaces.1 1. This paper is the full translation from the transactions of JSME, Series C, Vol.76, No.763, pp. 611-618, 2010.
-  ISO/CD12100, “Safety of machinery – Basic concepts, general principles for design,” 1998.
-  ISO10218, “Robots for industrial environments – Safety requirements, Part 1: Robot,” 2006.
-  T. Aoki and K. Taguchi, “Human-Assist Robot for Nursing Use,” J. of Robotics and Mechatronics, Vol.13, No.2, pp. 183-189, 2001.
-  A. Goswami, M. A. Peshkin, and J. E. Colgate, “Passive Robotics: An Exploration of Mechanical Computation,” Proc. of 1990, IEEE Int. Conf. on Robotics and Automation, pp. 279-284, 1990.
-  M. A. Peshkin and J. E. Colgate, “Cobots,” Industrial Robot, Vol.26, No.5, pp. 335-341, 1999.
-  M. Higuchi, “Working Auxiliary Arm,” Japanese Patent Application No.JP20030410620 20031209, Japanese Patent Publication No.JP2005169536, Japanese Patent No.4115927, 2008 (in Japanese).
-  M. Higuchi, “Development of a Human Symbiotic Assist Arm “PAS-Arm” (Basic Concept and Mechanism),” Trans. of the Japan Society of Mechanical Engineers, Series C, Vol.73, No.730, pp. 1762-1768, 2007 (in Japanese).
-  M. Higuchi, “Development of a Human Symbiotic Assist Arm “PAS-Arm” (Design of Mechanism·CVT and Experimental System),” Trans. of the Japan Society of Mechanical Engineers, Series C, Vol.75, No.749, pp. 104-112, 2009 (in Japanese).
-  T. Yoshikawa, “Analysis and Control of Robot Manipulators with Redundancy,” Proc. of 1st Int. Symposium of Robotics Research, MIT Press, Cambridge, MA, pp. 735-747, 1984.
-  JIS B8436, “Circular Flanged Mechanical Interfaces of Industrial Robots,” 1989.
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