【正文】 y assumption, which neglects the presence of distributed or concentrated elasticity, can make that control input frequencies of the switcher excite neglected resonant modes. Furthermore, in discretetime systems discontinuous control fails to ensure the sliding mode and has to be replaced by continuous control (Young et al., 1999). Avoiding discontinuousfeedback control issues associated with unmodelled dynamics and related chattering are no longer critical. Chattering bees a nonissue. In plants where control actuators have limited bandwidth there are two possibilities: actuator bandwidth is outside the required closedloop bandwidth, or, the desired closedloop bandwidth is beyond the actuator bandwidth. In the fist case, the actuator dynamics are to be considered as the nonmodelled dynamics. Consequently, the sliding mode using discontinuous VSS control cannot occur, because the control plant input is continuous. Therefore, the disturbance estimation approach is preferred rather than VSS disturbance rejection. In the second case, the actuator dynamics are to be lumped together with the plant. The matching conditions (Draz\enovicH, 1969) for disturbance rejection and insensitivity to parameter variations in the sliding mode are violated. This results from having dominant dynamics inserted between the physical input to the plant and the controller output. When unmatched disturbances exist the VSS control cannot guarantee the invariant sliding motion. This restriction may be relaxed by introducing a highorder sliding mode control in which the sliding manifold is chosen so that the associated transfer function has a relative degree larger than one (Fridman amp。 Levant, 1996). Such a control scheme has been used in a number of recently developed VSS control designs, . in Bartolini, Ferrara and Usai (1998). In the latter, the secondorder sliding mode control is invoked to create a dynamical controller that eliminates the chattering problem by passing discontinuous control action onto a derivative of the control input. The system to be controlled is given by Eqs. (1) ―(5) and the system output is the load position. The control objective is the position trajectory tracking. The control algorithm that is proposed in this paper has been developed following the idea of the VSS motion control presented by Jezernik. Since the elastic beltdrive behaves as a low bandwidth actuator, the conventional VSS control algorithm failed to achieve the prescribed control objective. Thus, the robust position trajectory tracking control algorithm presented in the paper has been derived using secondorder sliding mode control. In order to eliminate the chattering problem and preserve robustness, the control algorithm uses the continuous control law. Following the VSS disturbance estimation approach, it will be shown that the disturbance estimation feature of the proposed motion control algorithm is similar to the control approach of Jezernik (Jezernik et al., 1994). Additionally, the proposed control algorithm considers the actuator dynamics in order to reshape the poorly damped actuator bandwidth. Consequently, the proposed motion controller consists of a robust positiontracking controller in the outer loop and a vibration controller in the inner loop (Fig. 6). This section is anized as follows. Section presents the proposed VSS control design. Section describes the derivation of the robust position provides a description of the vibration controller. Finally, the proposed control scheme is described in Section . 激光切割機的傳動控制可變結(jié)構(gòu)系統(tǒng) 艾力斯?霍斯，卡瑞爾?詰責(zé)尼克，馬丁?特布 馬里博爾大學(xué)機器人學(xué)學(xué)院電氣工程系和計算機科學(xué)系 截稿于 1999 年 10 月 18日，出版與 2020 年 6月 2 日 . 內(nèi)容摘要﹕ 一種先進(jìn)的位置跟蹤控制算法已經(jīng)研制出來了， 并將其應(yīng)用在 激光切割機的數(shù)控運動控制器上 。激光切割機的 驅(qū)動 機構(gòu) 是由帶傳動機構(gòu)組成的。 彈性伺服機構(gòu)可以看成是一個彈簧連接的雙量機構(gòu)。由于存在彈力 ,摩擦力和干擾 ,利用可行的傳統(tǒng)的控制方法得到的閉環(huán)回路是有限的。因此 , 利用 可變系統(tǒng)結(jié)構(gòu)控制理論推導(dǎo)出運動控制算法。 算例分析表明文中有效控制 抑制機械振動和保證系統(tǒng)補償?shù)牟淮_定性。 因此 ,確保準(zhǔn)確的位置跟蹤 。 簡介： 對許多工業(yè)驅(qū)動器，運動控制的性能具有非常重要性。最高的利益是快速動態(tài)行為與準(zhǔn)確軌跡跟蹤。如應(yīng)用在機床必須滿足這些高的要求。激光切割機也是，它要求快速運動快速且高準(zhǔn)確度。這篇論文講述了激光切割機的一種低成本的建立在有兩個自由度的二維笛卡爾表基礎(chǔ)上的運動控制算法 (圖 1)。激光切割機的驅(qū)動機構(gòu)由有一個正時帶的帶傳動組成的。驅(qū)動系統(tǒng)中的正時帶具有吸引力是因為它具有高速度、高效、遠(yuǎn) 距離行進(jìn)和低成本特性 (霍斯 ,1996) 。另一方面 ,他們產(chǎn)生較多的不確定的動態(tài)和更高的傳動誤差。因此 ,傳動帶遭受較低的重復(fù)性和準(zhǔn)確性。此外 ,帶傳動動力學(xué)包括很多諧振頻率，即反饋控制中的不穩(wěn)定因素。因此 ,傳統(tǒng)的控制方法像比例積分控制、比例微分控制或 比例積分微分控制 未達(dá)到可接受的性能。設(shè)備參數(shù)的變化、不確定的動態(tài)和負(fù)載轉(zhuǎn)矩的干擾 ,以及機械