Hybrid input shaping to suppress residual vibration of flexible systems

Abstract

This paper presents a hybrid input shaping method to eliminate residual vibration of multi-mode flexible systems. This method, initially designed for one degree of systems, is modified to apply on linear and nonlinear multi-mode systems. In this method, firstly the flexible system is uncoupled using modal analysis method, and then the parameters of the decoupled system are used to shape the command template signal. A ramp plus ramped cycloid plus ramped versine is proposed as the command template signal to be preshaped. The template function is preshaped to yield zero residual vibration for point to point motion and then the resulting trajectory is convolved with a sequence of two impulses to obtain a twice shaped input. The proposed method is applied to eliminate residual vibration of a linear multimass and flexible joint manipulator types of systems. Simulation results show that the oscillations are considerably decreased with a high degree of robustness in the presence of system parameters uncertainty.

A New Trajectory Optimizing Method Using Input Shaping Principles

“…is method was selected because S filtered can appear as such a signal source. By using EMD, S filtered is decomposed into two parts, as shown by Figure 6 and (14). It should be noticed that the starting point and nal point of S 2 ′ is di erent with S 1 .…”

“…Another trajectory S 2add , which is similar with S 2 ′ , is added. After the compensating process, (14) becomes (15):…”

“…As the input shapers are decided, trajectory deviation and time-delay will be caused in convolving process, as shown in Figure 1(a). By adding trajectory compression process (C-IST), time-delay can be removed, as shown in Figure 1(b) [14]. However, damage of shaper's robustness will happen and trajectory deviation still remains.…”

A review of command shaping techniques for elimination of residual vibrations in flexible-joint manipulators

“…This sequence of impulses is obtained using the input shaping described in Section 4.1. to increase the robustness of the signal. The method suggested by Yavuz et al [25] is named as hybrid input shaping. For a specified travelling time and displacement, hybrid-shaping technique is implemented as follows;…”

“…Kapucu et al [24] on the other hand, suggested a hybrid input shaping method that includes convolution of a cycloid plus ramp function with two impulse sequences. Yavuz et al [25] proposed a hybrid input shaping method to eliminate residual vibration of multi-mode system by convolving the pre-shaped input of cycloid-plus-ramped versine-ramp function with the sequence of all modes generated by twoimpulse sequences. Conker et al [26] suggested an enhanced control technique for hybrid input shaping method to elimination of residual vibrations in flexible-joint manipulator.…”