Point-to-point motion commands that eliminate residual vibration

1994 ◽  
Author(s):  
T. M Chan
2004 ◽  
Vol 127 (4) ◽  
pp. 307-314 ◽  
Author(s):  
Jason Lawrence ◽  
William Singhose ◽  
Keith Hekman

Fast and accurate point-to-point motion is a common operation for industrial machines, but vibration will frequently corrupt such motion. This paper develops commands that can move machines without vibration, even in the presence of Coulomb friction. Previous studies have shown that input shaping can be used on linear systems to produce point-to-point motion with no residual vibration. This paper extends command-shaping theory to nonlinear systems, specifically systems with Coulomb friction. This idea is applied to a PD-controlled mass with Coulomb friction to ground. The theoretical developments are experimentally verified on a solder cell machine. The results show that the new commands allow the proportional gain to be increased, resulting in reduced rise time, settling time, and steady-state error.


1985 ◽  
Vol 107 (4) ◽  
pp. 378-382 ◽  
Author(s):  
P. H. Meckl ◽  
W. P. Seering

This paper describes an appropriately shaped forcing function for moving a dynamic system over an incremental distance with minimum residual vibration. The function is constructed by combining harmonics of a “ramped sinusoid” function so that minimum energy is introduced to the system at its resonant frequencies. A test fixture to evaluate this approach is described and experimental results are given. Residual vibration amplitudes for the ramped sinusoid function are compared with those for a square wave input and a bang-bang function. In practice, the ramped sinusoid achieves nearly an order-of-magnitude reduction in residual vibration amplitude as compared to the square wave forcing function.


2001 ◽  
Vol 123 (4) ◽  
pp. 733-736 ◽  
Author(s):  
Aurelio Piazzi ◽  
Antonio Visioli

A new technique, based on dynamic inversion, for the residual vibration reduction in the point-to-point motion of servosystems with elastic transmission is presented. The methodology consists of defining a suitable motion law for the load, and subsequently determining, via dynamic inversion, the corresponding command function for the system. The method inherently assures the robustness of the control scheme despite inaccuracies in the estimation of the stiffness constant and of the damping of the transmission. The main contribution of the paper lies in the definition of a simple optimization procedure which allows the system inversion point that minimizes the residual vibration to be found. Experimental results show that in this way the identification phase is less critical and performances can be significantly improved.


Robotica ◽  
1996 ◽  
Vol 14 (3) ◽  
pp. 339-345 ◽  
Author(s):  
Jung-Keun Cho ◽  
Youn-Sik Park

SUMMARYIn the authors' previous paper,10 an input shaping method was presented to reduce motion-induced vibrations effectively for various classes of flexible systems. In this paper, the effectiveness of the shaping method is experimentally demonstrated with a two-link flexible manipulator systemThe manipulator for experiments includes two revolute joints and two flexible links, and moves on a vertical plane under gravity. An analytic model is developed considering the flexibility of the system and its joint stiffness in order to derive an appropriate estimation of dynamic modal properties. The input shaping method used in this work utilizes time-varying modal properties obtained from the model instead of the conventional input shaping method which employs time-invariant modal properties. A point-to-point motion is tested in order to show the effectivess of the proposed shaping method in vibration reduction during and after a given motion. The given reference trajectories are shaped to suppress the motion induced vibration. The test results demonstrate that the link vibration can be greatly suppressed during and after a motion, and the residual vibration reduction was observed more than 90% by employing this time-varying impulse shaping technique.


Author(s):  
Xin-Jun Liu ◽  
Zhao Gong ◽  
Fugui Xie ◽  
Shuzhan Shentu

In this paper, a mobile robot named VicRoB with 6 degrees of freedom (DOFs) driven by three tracked vehicles is designed and analyzed. The robot employs a 3-PPSR parallel configuration. The scheme of the mechanism and the inverse kinematic solution are given. A path planning method of a single tracked vehicle and a coordinated motion planning of three tracked vehicles are proposed. The mechanical structure and the electrical architecture of VicRoB prototype are illustrated. VicRoB can achieve the point-to-point motion mode and the continuous motion mode with employing the motion planning method. The orientation precision of VicRoB is measured in a series of motion experiments, which verifies the feasibility of the motion planning method. This work provides a kinematic basis for the orientation closed loop control of VicRoB whether it works on flat or rough road.


Author(s):  
S W Kim ◽  
J S Park

An optimum design methodology is presented for point-to-point motion control servo systems in which d.c. permanent magnetic motors are used as the main actuators. Emphasis is focused on establishing a series of comprehensive decision-making practices in dealing with three major design subjects: determination of the velocity profile, optimization of the speed reduction ratio, and selection of the motor. Finally, a practical design example is discussed to illustrate how the suggested design methodology may be applied to actual design problems.


Sign in / Sign up

Export Citation Format

Share Document