We analyzed the stability of dynamic object manipulation through a soft interface, viscoelastic interface material between the manipulating finger and manipulated object. The system was described in continuous-discrete time system (Figure 1). We showed that the stability of the system depended on viscoelasticity of the soft interface for feedback control. In particular, we pointed out that, in critical stability, the relationship between the viscosity of the material and sampling time is not monotonous (Figure 2). From results of the stability analysis, we propose a basis for materials selection for a soft interface for feedback control. In addition, we have confirmed the analysis experimentally. In this experiment, we use Variable Dynamics Fingertip (VDF) (Figure 3).
Fig.1: Feedback system of dynamic manipulation through a soft interface
Fig.2: Critical sampling time for viscosity
Fig.3: Variable dynamics fingertip (VDF)
Publications
- Mizuho SHIBATA, Shinichi Hirai, "Modeling and Stability Analysis of Dynamic Control through a Soft Interface", Journal of Robotics and Mechatronics, Vol.18, No.3, pp. 242-248, 2006
- Mizuho Shibata，Shinichi Hirai，"Stability Analysis for Dynamic control on Contact with Soft Interface in Continuous-discrete Time System"， Proc. IEEE/RSJ Int. Conf. on Intelligent Robots and Systems, pp.1628-1633, 2005
- Mizuho Shibata，Shinichi Hirai，"Stability and Graspability Analysis in Grasping Task Taking Fingertip Dynamics into Consideration"， Proc. IEEE/RSJ Int. Conf. on Intelligent Robots and Systems, pp.3686-3691, 2004