交叉耦合自适应神经元控制器应用于抛物线轨迹加工中的研究

本文综合了自适应神经元控制器与交叉耦合控制方法的优点,引入轮廓误差的二次性能指标,设计了应用于抛物线轨迹加工的交叉耦合自适应神经元控制器。该控制器具有良好的自适应学习能力,无须对控制对象建模,结构简单,实时性好,实验证明可有效减小抛物线轮廓误差。     

Development of a decentralized multi-axis synchronous control approach for real-time networks

The message scheduling and the network-induced delays of real-time networks, together with the different inertias and disturbances in different axes, make the synchronous control of the real-time network-based systems quite challenging. To address this challenge, a decentralized multi-axis synchronous control approach is developed in this paper. Due to the limitations of message scheduling and network bandwidth, error of the position synchronization is firstly defined in the proposed control approach as a subset of preceding-axis pairs. Then, a motion message estimator is designed to reduce the effect of network delays. It is proven that position and synchronization errors asymptotically converge to zero in the proposed controller with the delay compensation. Finally, simulation and experimental results show that the developed control approach can achieve the good position synchronization performance for the multi-axis motion over the real-time network.     

Biaxial contouring control with friction dynamics using a contour index approach

In conventional designs, contouring control is usually decomposed into independent tracking tasks of axes. Its success relies on good tracking performance of each axis, which is difficult to achieve when the dynamics of each axis is different from each other and subjected to nonlinear frictions and load variations. Additionally, another difficulty in contouring control is the formulation of a contouring error model and real-time estimation of contouring error. Therefore, in this paper, a contour following strategy was developed to improve contouring accuracy without depending on axial tracking performance. The proposed contouring error model is formulated systematically based on the coordinated transformation scheme. A contour index (CI) is evaluated geometrically, which can be treated as an equivalent contour error such that a reduction in CI implies a reduction in contour error. With the proposed approach, the resulting contour performance will not be degraded if the tracking task of each axis is not carried out precisely. Experiments were conducted using a bi-axial linear stage and the results demonstrate that the contouring qualities were still maintained at high feed-rates even in the presence of undesirable tracking lags.     

DESIGN OF LIGHTWEIGHT PUF CIRCUIT BASED ON SELECTABLE CROSS-COUPLED INVERTERS

By analyzing the principle of process variations, a lightweight Physical Unclonable Function(PUF) circuit based on selectable cross-coupled inverters is proposed in this paper. Firstly, selectable cross-coupled inverters are chosen for two delay paths. Simultaneously, the circuit takes challenge signal to control each delay path. The PUF cell circuit is implemented in Semiconductor Manufacturing International Corporation(SMIC) 65 nm CMOS technology and the layout area is 2.94 mm × 1.68 mm. Then the 64-bit PUF circuit is achieved with the cascade connection of cell circuits. The simulation results show that the randomness is 49.4% and the reliability is 96.5%. Compared to the other works, this PUF circuit improves the encrypt performance and greatly reduces the area.     

Integral design of contour error model and control for biaxial system

This paper focuses on the contour following accuracy improvement for biaxial systems using cross-coupled control (CCC). It proposes an integral design method including contour error model, contour control effort distribution and the CCC algorithm. First, a contour error model using the contour algebraic equation and its partial derivatives is established without the small tracking error assumption. This model satisfies the condition that it equals to zero if and only if the real contour error value vanishes, which makes perfect contour following become possible in theory. Then, in order to decouple the contour following the feed-direction tracking, contour control effort distribution is decided to be in line with the normal vector at the desired point. Through expanding the proposed contour error model with Taylor series to make it be related to tracking errors of both axes, the stability condition of CCC is analyzed by the contour error transfer function (CETF). Experiments are carried out on an X–Y motion stage to verify the proposed method. The results show that it improves the contour following accuracy greatly in various conditions, even when large tracking errors occur.     

一种进给伺服系统非线性PID交叉耦合控制

提高多轴伺服系统的轮廓跟随性能是现代计算机数控加工的重要应用之一。针对传统交叉耦合控制方法对自由曲线轨迹的轮廓跟踪精度较差以及传统PID控制系统抗扰性和鲁棒性较差的问题,提出一种基于自抗扰控制的交叉耦合轮廓误差补偿综合控制策略,该策略由用于位置环反馈控制和轮廓误差补偿的新型非线性PID (NLPID )、位置伺服控制器 TNP-ADRC 和基于NLPID的变增益交叉耦合控制器组成。在MATLAB/Simulink环境下对方波信号跟踪和标准圆轮廓加工过程中轮廓误差的变化情况进行仿真,仿真结果表明：与传统PID交叉耦合控制相比,该方法不仅能够有效提高系统的鲁棒性以及抗干扰能力,并且能够显著提高多轴运动控制系统的轮廓加工精度。     

H型平台双环交叉耦合滑模同步控制

为提高H型平台双直线电机运动控制系统的抗干扰能力和同步运动性能,提出一种基于位置环和速度环双环偏差的交叉耦合滑模同步控制方法。采用交叉耦合算法建立双直线电机偏差（跟踪误差）的耦合关系,输出同步误差,并结合滑模控制器,实现跟踪误差与同步误差的同时收敛。基于仿真实验对比分析单位置环、单速度环和位置-速度双环3种交叉耦合结构的滑模控制在扰动输入后的位置跟踪性能和同步控制性能。仿真结果表明：位置-速度双环控制方的电机位置跟踪性能和同步控制性能较单位置环控制方法分别提升60.6%和51.95%,较单速度环控制方法分别提升85.0%和41.91%,为平台的同步性控制应用提供了参考。     

Robust trajectories following control of a 2-link robot manipulator via coordinate transformation for manufacturing applications

A common idea concerning trajectory control of robot manipulators is to tackle the motion of the end-effector. According to traditional trajectory designs, a prescribed profile in a work space is first decomposed into independent joint positions such that the success in a contouring task lies with good tracking capability of individual joints. To advance trajectory control precision without relying on high tracking performance, a contour control strategy for a robot manipulator is presented in this paper. Different from the traditional concept of trajectory control, a contour following control strategy is developed via a coordinate transformation scheme. The main advantage of the proposed control architecture is that the final contouring accuracy will not be degraded in case the tracking performance of the robot manipulator is not good enough. Moreover, using a concept of variable structure control theory, a smooth robust control algorithm is realized in the form of proportional control plus an integration term. The robustness of the control algorithm is also demonstrated. A number of experiments are conducted to demonstrate the advantage of the trajectories following control framework and validate the feasibility of the proposed controller.     

CCPLL在抗共道多卜勒干扰中应用的研究

机载转发式干扰机施放的速度欺骗干扰是一种共道干扰。目前还没有抗这类干扰的较好措施。研究结果证实,采用交叉耦合锁相环(CCPLL)结构构成的抗共道多卜勒干扰电路在一定信噪比下可抗这类干扰,从强干扰中提取出有用的弱目标回波信号。