1、 外文文献原文 Limited torque input Robust Adaptive Tracking Control of Robot Abstract Based on input constraints, a novel robust-adaptive tracking control algorithm is proposed for robot manipulators since stability if the standard adaptive control system is problematic when some disturbance exists. The p
2、roposed controller stabilizes the system with some disturbance and guarantees asymptotic stability in the case if non-disturbance. Robust-adaptive algorithm can be received as the extension of the conventional adaptive scheme. The estimated parameters enter the controller non-linearly and the result
3、ing closed-loop system. The algorithm provides further flexibility fir adaptive controller design and better transient performance and robustness to disturbance and error of estimated parameter-region especially. Simulation results demonstrate it effectiveness. Keywords: Adaptive control； robot mani
4、pulator； parametric uncertainties； robust-adaptive； So far, almost all of the controller design is based on joint drive to produce any torque on the basis of； and is subject to the physical conditions, the output of the drive torque is limited, so the controller may lead to the control failure or de
5、terioration of the quality control.Therefore the controller design must take into account the limited joint drive dynamic capability. For example, the operation of the industry to help the robot, some parameters are uncertain or unknown, adaptive control is based on the estimated parameters to deal
6、with such issues one of the main control strategy, using the robot dynamic equations of linear parametric nature, through an integral operator estimates the robot parameters. As integral part of the role in the continued interference conditions, stability control system is not easy, so appropriate t
7、o limit or adjust the integral part of the role of the adaptive system to achieve an effective means of stabilization. Son ah estimated parameters can limit the extent required, thereby increasing the robustness of adaptive control system. However, this algorithm has six switch component, a little c
8、omplicated, but really is the parameter is not specified range, it cannot give the system control quality and robustness of information. This paper presents a simple robust adaptive control algorithm, when the estimated parameters field contains the parameters of the true value, the closed-loop syst
9、em to achieve asymptotically stable tracking； when there is interference or the estimated parameters with the true value of free parameter that is when the error system is stable. 1. MANIPULATOR DYNAMIC MODEL AND CHARACTERISTIC MODEL Consider a robotic manipulator with n degrees of freedom. The cont
10、inuous Lagrange dynamic model is given by ( ) ( , ) ( )M q q C q q q G q u Where q Rn and q R nare the vector of generalized joint coordinates and velocity coordinates, respectively. The inertia matrix M(q)-MT(q) 0 ， and there exist two constant positive scalars M min and M max such thatminM M maxM,
11、 nuR is the vector of commanded generalized force, and ( , )Cqqq and G(q) are the terms due to Carioles, Centripetal and gravity forces. In actual application, the uncertain parameters and un-modeled dynamics usually exist in the established dynamic model in (1). When the sample time sTis small enou
12、gh, at instant t=k sT q and q can be approximated by ( ) ( 1)sq k q kq Tand2( 1 ) 2 ( ) ( 1 )sq k q k q kq T . Respectively Using the above relationships thediscrete-time representation of (1) becomes 1221 1SM q k q k f k q k f k q k G k u kT (2a) Premultiplying(2a) by 21sT mM q kresults in 1211q k
13、f k q k f k q k G k k u k where 11 2,sf k I T M q k C q k q k , 12 ,sf k I T M q k C q k q k 2121ssG k T M q k G q kk T M q k and I denotes the unitary diagonal matrix with an appropriate dimension. If the designed ,u t q q ,u t q q is continuous in t ,q and q , then the solution (q, q ) of (1) will
14、 be continuously differentiable. Let 1,W q q M q C q q and ,ijw q q be ij-th element of matrix ,ijW q q ； We define 1 1 11 1SF k f k f kT and then F1(k) can be expressed as 1 , 1 , 1F k W q k q k W q k q k For the ij-th element f1,ij(k) of matrix F1(k) we can get 1, , 1 , 1i j i j i jf k w q k q k w q k q k = 11 11, | 1ij q q kTq q kw q q q k q kq
