A two-speed actuator for robotics with fast seamless gear shifting (2405.16652v1)
Abstract: This paper present a novel dual-speed actuator adapted to robotics. In many applications, robots have to bear large loads while moving slowly and also have to move quickly through the air with almost no load. This lead to conflicting requirements for their actuators. Multiple gear ratios address this issue by allowing an effective use of power over a wide range of torque-speed load conditions. Furthermore, very different gear ratios also lead to drastic changes of the intrinsic impedance, enabling a non-back-drivable mode for stiff position control and a back-drivable mode for force control. The proposed actuator consists of two electric motors coupled to a differential; one has a large gear ratio while the other is almost direct-drive and equipped with a brake. During the high-force mode the brake is locked, only one motor is used, and the actuator behaves like a regular highly-geared servo-motor. During the high-speed mode the brake is open, both motor are used at the same time, and the actuator behaves like a direct drive motor. A dynamic model is developed and novel controllers are proposed for synergic use of both motors. The redundancy of motors is exploited for maintaining full control of the output during mode transitions, allowing for fast and seamless switching even when interacting with unknown environments. Results are demonstrated with a proof-of-concept linear actuator.
- S. Hirose, “A study of design and control of a quadruped walking vehicle,” The International Journal of Robotics Research, vol. 3, no. 2, pp. 113–133, Jun. 1984.
- J. Hollerbach, I. Hunter, and J. Ballantyne, “A comparative analysis of actuator technologies for robotics,” in The Robotics Review, MIT press ed., 1992, vol. 2, pp. 299–342.
- N. Hogan and S. Buerger, “Impedance and interaction control,” in Robotics and Automation Handbook. CRC Press, 2004.
- H. Hanafusa and H. Asada, “Stable prehension by a robot hand with elastic fingers,” Proc. 7th Int. Symp. Industrial Robots, pp. 361–368, 1977.
- G. Pratt and M. Williamson, “Series elastic actuators,” in IEEE/RSJ International Conference on Intelligent Robots and Systems, vol. 1, Aug. 1995, pp. 399–406 vol.1.
- P. Fauteux, M. Lauria, B. Heintz, and F. Michaud, “Dual-differential rheological actuator for high-performance physical robotic interaction,” IEEE Transactions on Robotics, vol. 26, no. 4, pp. 607 –618, Aug. 2010.
- G. Tonietti, R. Schiavi, and A. Bicchi, “Design and control of a variable stiffness actuator for safe and fast physical human/robot interaction,” in IEEE International Conference on Robotics and Automation, Apr. 2005, pp. 526–531.
- K. Koganezawa, T. Nakazawa, and T. Inaba, “Antagonistic control of multi-DOF joint by using the actuator with non-linear elasticity,” in IEEE International Conference on Robotics and Automation, May 2006, pp. 2201–2207.
- D. Leach, F. Gunther, N. Maheshwari, and F. Iida, “Linear multi-modal actuation through discrete coupling,” in IEEE/RSJ International Conference on Intelligent Robots and Systems (IROS), Oct. 2012, pp. 2437–2442.
- B.-S. Kim, J.-B. Song, and J.-J. Park, “A serial-type dual actuator unit with planetary gear train: Basic design and applications,” IEEE/ASME Transactions on Mechatronics, vol. 15, no. 1, pp. 108–116, 2010.
- J. B. Morrell and J. K. Salisbury, “Parallel-coupled micro-macro actuators,” The International Journal of Robotics Research, vol. 17, no. 7, pp. 773–791, Jul. 1998.
- N. McKeegan, “Antonov’s 3-speed transmission for electric vehicles boosts efficiency by 15 percent,” Jul. 2011. [Online]. Available: http://www.gizmag.com/antonov-3-speed-transmission-ev/19088/
- S. Bologna, “Electric propulsion system for vehicles,” U.S. Patent US8 739 655 B2, Jun., 2014.
- H. Lee and Y. Choi, “A new actuator system using dual-motors and a planetary gear,” IEEE/ASME Transactions on Mechatronics, vol. 17, no. 1, pp. 192–197, 2012.
- “Maxon motor: Small dc motors and drive systems.” [Online]. Available: www.maxonmotorusa.com