1. 2) H. Hogan: “Adaptive Control of Mechanical Impedance by Coactivation of Antagonist Muscles,” IEEE Transactions on Automatic Control, vol.AC-29, no.8, pp.681–690, 1984.
2. 3) N. Hogan: Mechanical impedance of single- and multiarticular systems. in J. M. Winters and S. L.-Y. Woo (eds.), Multiple muscle systems: Biomechanics and movement organization, pp.149–164, 1990.
3. 5) N. Hogan: “Impedance Control: An Approach to Manipulation: Part I—Theory, Part II—Implementation, Part III—Applications,” J. of Dyn. Syst., Measurement Contr., vol.107, pp.1–24, 1985.
4. 6) K. Kosuge, K. Furuta and T. Yokoyama: “Mechanical Impedance Control of a Robot Arm by Virtual Internal Model Following Controller,” Proc. of the IFAC 10 World Congress on Autonomous Control, vol.4, pp.250–255, 1987.
5. 8) A. Albu-Schaffer, et al.: “The DLR Lightweight robot: design and control concepts for robots in human environments,” Industrial Robot: An International Journal, vol.34, no.5, pp.376–385, 2007.