Time-suboptimal reference trajectories are presented in this paper for vibration-free positioning of 1-DOF undamped linear flexible systems. The trajectories are obtained by applying shaping techniques; that is, firstly the profiles are parameterized in time domain, and then the parameter values are determined to satisfy conditions specified both in time and frequency domains. Closed-form solutions are available in the undamped case. Since time-optimal problems subject to acceleration and velocity constraints are solved, positioning time of the resulting trajectories are minimized; positioning time shorter than the well-known UM-ZV shaper can be achieved in some cases. Implementation issues which arise when a discrete-time controller is used to generate the proposed trajectory are also investigated and solved. The trajectories are implemented in a positioning controller and the vibration suppression performance is verified through experiments as well as numerical simulations.

Deals with the coordinated controller design for a certain kind of cooperative manipulation of an unstable object with multiple robotic manipulators. Based on the system description in the framework of differential-algebraic equations (DAEs), control problems of the object manipulation with single and two manipulators are formulated. By characterizing a hand-over operation as a result of the simultaneous solution to the both problems, a reliable-controller design technique is applied to derive the controllers. Thus formulating the hand-over control problem as a reliable control problem derives a class of the object which can be handed over at least by using the proposed control scheme and a constructive design method of the controllers. The experimental results are included.

A new controller-design framework for cooperating manipulators is considered in this paper based on a reliable controller design concept. The objective of this paper is to derive a set of controllers for cooperating manipulation especially which can hand over an object. The key idea is to reformulate the original problem of coordinated control as reliable stabilization problem; i.e., to design a set of controllers which can stabilize a plant both jointly and alone. By introducing a kind of strict force control scheme in the workspace, the reliably stabilizing controller design technique is applied to derive the controllers. Two contributions are existing: (i) clarifying a class of the object which can be handed over at least by using the proposed control scheme and (ii) presenting a constructive design method of the controllers. Experimental results on the hand-over control of a 2D inverted pendulum with two 6-DOF manipulators are included.