Computer-aided integrated design for mechatronic systems with varying dynamics

in Ulbrich, Heinz; Ginzinger, Lucas (Eds.) Motion and Vibration Control (Selected Papers from MOVIC 2008) (2009)

Some mechatronic systems have different spatial configurations or operation positions, and, as a consequence, their dynamic behavior, described by their most significant eigenfrequencies and mode-shapes ... [more ▼]

Some mechatronic systems have different spatial configurations or operation positions, and, as a consequence, their dynamic behavior, described by their most significant eigenfrequencies and mode-shapes, may vary in the configuration space. This inevitably affects the performance and the stability of the control system. Regarding the design of mechatronic systems with variable configuration, two main issues are treated in this paper: (i) the derivation of a parametric model able to capture the varying dynamics and the control actions, (ii) the integrated design of the structure and the controller. To cope with these issues, a parametric model is derived using a flexible multibody system technique based on the finite element method. A global modal parameterization is applied for model-order reduction, yielding a concise description of the flexible multibody model. A linear parameter varying controller is derived via interpolation of local controllers for the reduced models. This methodology is applied to a pick-and-place assembly robot with a gripper carried by a flexible beam. Eventually, design tradeoffs are evaluated considering the performance of the active system for different structural configurations. [less ▲]

Computer-aided integrated design for mechatronic systems with configuration-dependent dynamics

Conference (2008, May)

Mechatronics deals with the integrated design of a mechanical system and its control system. Moreover, a large number of mechatronic systems may have their natural frequencies and mode shapes dependent on ... [more ▼]

Mechatronics deals with the integrated design of a mechanical system and its control system. Moreover, a large number of mechatronic systems may have their natural frequencies and mode shapes dependent on their spatial configuration, which inevitably affects the performance and the stability of the control system. In particular, mechatronic systems, such as machine tools and pick-and-place robots, can be classified as systems with configuration-dependent dynamics, since the relative motion between their flexible components can lead to time-varying boundary conditions. A parametric model able to capture this behavior is proposed using finite element based flexible multibody method. A global modal parameterization is applied for model-order reduction. A linear parameter varying model is derived from these reduced models and can be used in a control design scheme. This methodology is applied to a pick-and-place assembly robot with a gripper carried by a flexible beam (Fig. 1a). Vibrations, which depend on the beam length, decrease the throughput of the machine (Fig. 1b). Linear time invariant and linear parameter varying control strategies are evaluated using the derived linear parameter varying model. [less ▲]