外文翻譯--機械手非線性擾動器的設計（英文）

1、Nonlinear Disturbance Observer Design For Robotic ManipulatorsA. Mohammadia,?, M. Tavakolib,??, H. J. Marquezb, F. Hashemzadehb,aEdward S. Rogers Sr. Department of Electrical & Computer Engineering, University of Tor

2、onto, Toronto, Ontario, Canada M5S 3G4 bDepartment of Electrical & Computer Engineering, University of Alberta, Edmonton, Alberta, Canada T6G 2V4AbstractRobotic manipulators are highly nonlinear and coupled systems t

3、hat are subject to different types of disturbances such as joint frictions, unknown payloads, varying contact points, and unmodeled dynamics. These distur- bances, when unaccounted for, adversely affect the performance o

4、f the ma- nipulator. Employing a disturbance observer is a common method to reject such disturbances. In addition to disturbance rejection, disturbance ob- servers can be used in force control applications. Recently, res

5、earch has been done regarding the design of nonlinear disturbance observers (NLDOs) for robotic manipulators. In spite of good results in terms of disturbance tracking, the previously designed nonlinear disturbance obser

6、vers can merely be used for planar serial manipulators with revolute joints (Chen, W.H., Bal- lance, D.J., Gawthorp, P.J., O’Reilly, J., 2000. A nonlinear disturbance ob- server for robotic manipulators. IEEE Trans. Ind.

7、 Electron. 47, 932–938), (Nikoobin, A., Haghighi, R., 2009. Lyapunov-based nonlinear disturbance observer for serial n-link manipulators. J. Intell. Robot. Syst. 55, 135–153). In this paper, a general systematic approach

8、 is proposed to solve the distur- bance observer design problem for robotic manipulators without restrictions on the number of degrees-of-freedom (DOFs), the types of joints, or the ma- nipulator configuration. Moreover,

9、 this design method does not need the exact dynamic model of the serial robotic manipulator. This method also?Corresponding author, Tel.: +1 (647)978-0140 ??Principal corresponding author, Tel.: +1 (780)492-8935, fax: +1

10、 (780)492-1811 Email addresses: alireza.mohammadi@mail.utoronto.ca (A. Mohammadi), mahdi.tavakoli@ualberta.ca (M. Tavakoli), hmarquez@ualberta.ca (H. J. Marquez), farzad.hashemzadeh@ualberta.ca (F. Hashemzadeh)Preprint s

11、ubmitted to Control Engineering Practice October 22, 2012This paper appears in Control Engineering Practice, 2012. http://dx.doi.org/10.1016/j.conengprac.2012.10.008Figure 1: Block diagram of a typical disturbance observ

12、er in a robotic application.application of disturbance observers is in improving manipulator tracking performance through friction estimation and compensation (Bona and In- dri, 2005), (Sawut et al., 2001). In (Mohammadi

13、 et al., 2011a), the authors proposed a nonlinear disturbance observer- based control law that guar- anteed asymptotic trajectory and disturbance tracking in the presence of slow-varying disturbances. One important aspec

14、t of disturbance observer-based friction compensa- tion schemes is in that they are not based on any particular friction models (Bona and Indri, 2005). Disturbance observers have recently been used in time-delayed bilate

15、ral teleoperation in order to improve the transparency of telerobotic systems (Natori et al., 2010), (Natori et al., 2007) and (Natori et al., 2006). In time-delayed teleoperation, the delayed position/force sig- nals ar

16、e received from the communication channel in the master and the slave sides. The time-delayed position/force signals are then added to the output of the disturbance observer in order to provide the master and the slave r

17、obots with estimation of the undelayed versions of the position/force sig- nals and thus improve the teleoperation system transparency (Natori et al., 2010). In (Mohammadi et al., 2011b), the authors implemented a pair o

18、f nonlinear disturbance observers in a 4-channel bilateral teleoperation ar- chitecture to achieve full transparency in the absence of communication time delays in both free and constrained motions. In that work, however

19、, the availability of joint acceleration measurements, which is necessary for achieving full transparency, simplified design of disturbance observers. Besides disturbance rejection, disturbance observers have found appli

20、ca- tions in other robotics contexts. In many robotics applications, the robot end-effector comes in contact with a compliant surface and a force control scheme is needed to guarantee good system performance. Therefore,