基于双DSP的导引头数字控制系统设计

分析了导引头伺服系统的结构及其预置、稳定、搜索和跟踪等回路的功能.设计了基于双DSP结构的导引头伺服系统控制器,以实现导引头的通信、扰动隔离以及目标跟踪等功能,介绍了其硬件与软件实现方法.分析了导引头伺服系统的扰动隔离与目标跟踪原理,并以方位轴稳定回路为例,提出了基于dSPACE半实物仿真系统的数字控制器设计方法.扰动隔离仿真与目标跟踪试验结果表明:所设计的导引头数字控制系统具有较高精度,基本满足导引头的扰动隔离与目标跟踪功能.     

捷联稳定技术在两轴光电跟踪仪中的应用

载体平台摇摆对两轴光电跟踪仪光轴指向的扰动是制约光电跟踪仪跟踪稳定性和跟踪精度提高的关键因素.本文首先从控制原理出发比较了传统速率稳定方式与捷联稳定方式,然后针对两轴光电跟踪仪捷联稳定方式建立了扰动作用于光轴指向分量的数学模型,最后对某型光电跟踪仪采用了捷联稳定技术,并设计了相应的伺服系统,试验表明此系统设计合理,满足...     

舰载视轴稳定系统的变结构控制研究

为了消除舰船摇摆对舰载光电跟踪设备稳定精度的影响,提高系统视轴稳定性能,根据舰船摇摆对视轴偏差影响的随机性,在描述视轴稳定回路的基础上,设计视轴稳定滑模变结构控制器,并引入约束条件,以减弱系统抖振.利用AR序列预测估计方法,实现视轴偏差预测估计,完成视轴稳定滑模变结构控制律的求取,并利用matlab仿真软件,对视轴稳定滑模变结构控制律进行数字计算.仿真结果表明,该控制方法能有效地消除了陀螺测量随机噪声带来的影响,减弱了系统抖振,对舰载视轴稳定有良好的性能.     

隔振对光电跟踪系统频率特性的影响及其抑制

针对隔振对光电跟踪系统频率响应特性的影响,从带隔振装置的光电跟踪系统动力学模型入手,研究了系统频率特性的变化规律.提出了两种抑制隔振装置影响的思路:调整隔振装置机械结构设计,改善基座的角运动谐振特性;通过调整方位轴控制策略消除基座晃动对跟踪控制的不利影响.对后一种思路进行了深入的研究,将基座和光电系统的角位置和角速度实测信息作为状态变量,采用状态反馈配置极点的方法,消除速度响应环节的谐振极点,抵消谐振零点.对安装在隔振装置上的某光电跟踪系统进行仿真实验结果,在保证稳定的前提下,状态反馈配置极点方法将稳态振荡的幅值由2.4×10-4 rad减小到7×10-6 rad.结果表明,采用状态反馈配置系统速度响应环节闭环期望极点的方法可以有效抑制隔振装置对光电跟踪系统频率特性的影响.     

全捷联导引头的惯性视线角速度解耦方法及精度分析

针对全捷联导引头固联于弹体且其测量信息不能直接构成制导指令的问题,提出了一种新型的惯性视线角速度直接解耦方法.与传统方法相比,该方法不需要测量弹体姿态角,而是通过引入体视线角的导数、弹体姿态角速度以及相对运动学关系来进行姿态解耦,直接重构出弹体坐标系下的惯性视线角速度,并给出惯性视线角速度在视线系及体视线系下投影的计算方法;通过推导映射函数的雅克比矩阵,给出了从体视线角的导数和弹体角速度到惯性视线角速率的误差传递函数;通过对误差传递函数的分析,讨论了影响惯性视线角速率解耦精度的因素.仿真结果表明该方法实用有效,具有一定应用参考价值.     

视轴偏角对三轴光电跟踪系统跟踪过程的影响

地平式、X-Y式光电跟踪系统存在空间跟踪盲区。三轴光电跟踪系统通过跟踪方式切换可以解决空间跟踪盲区问题,但视轴偏角使得脱靶量到轴转动量的转换不同于常规地平式跟踪系统,同时使系统具有不可见区域。分析和仿真表明:视轴偏角较小时,脱靶量与轴驱动量的转换可用常规地平式跟踪系统中的方法近似,否则,需用不同的计算方法;在三轴跟踪系统退化成的地平式跟踪系统的天顶跟踪盲区外即可进行跟踪方式切换。     

地平式光电跟踪系统动力学模型分析及其虚拟样机技术仿真

结合动量定理和动量矩定理分析了地平式光电跟踪系统的动力学特性,建立了地平式光电跟踪系统的非线性模型,并用虚拟样机技术对其非线性模型进行仿真.理论分析与仿真结果表明,当方位轴和俯仰轴均以较高的角速度或角加速度运动时,因非线性关系所导致的扰动力矩会严重影响系统的跟踪精度,当地平式光电跟踪系统的俯仰轴相对其各惯性主轴的转动惯量相等时,可彻底解决俯仰轴与方位轴之间的运动偶合关系.     

导引头伺服系统的输出多采样率变结构控制

针对弹体耦合干扰力矩,摩擦力矩及参数扰动对导引头伺服系统跟踪性能的影响,基于输出多采样和区域极点配置技术,研究了导引头伺服系统的输出多采样率变结构控制,给出了确定控制器参数的方法.所设计的控制器能保证闭环系统是有界稳定的,且无需利用系统的状态作为反馈而仅利用输出采样来设计控制器,因而无须伺服机构中安装测速单元,有效节省了机构的体积和重量,有较强的实用性且易于实现.仿真结果表明,所设计的控制器对弹体耦合干扰力矩及系统参数扰动有较强的鲁棒性,且具有较高的跟踪精度,因而在导引头伺服系统这类对体积和质量有严格限制的伺服系统中具有较好的应用前景.     

机载光电陀螺稳定平台的伪微分反馈控制

为了克服外部干扰对机载光电陀螺稳定平台的影响,实现高稳定精度和隔离度,采用基于伪微分反馈的控制技术对系统的控制性能进行了研究.首先,介绍了伪微分反馈控制技术的基本结构,并对其进行了简化.从理论上分析了简化的伪微分反馈控制技术在控制结构和控制性能上较经典PI控制的优势;然后,提出采用试凑法对伪微分反馈控制器进行参数整定的整定策略;最后,以某型号机载光电陀螺稳定平台为研究对象,对伪微分反馈控制器和PI控制器在抗力矩扰动、隔离载机角速率扰动和控制对象模型摄动等方面进行了仿真对比实验.实验结果表明,在相同的闭环带宽情况下,采用简化的伪微分反馈控制器的机载光电陀螺稳定平台的阶跃响应具有更小的超调,更短的上升和调节时间.在陀螺噪声存在的情况下,该控制器能够有效地抑制力矩和载机的姿态扰动对系统性能的影响;并且对被控对象的模型摄动具有较强的鲁棒性.     

大口径光电望远镜风阻力矩自抗扰补偿研究

光电望远镜口径超过5m以后,应该补偿风阻力矩干扰,以提高光电望远镜跟踪精度.本文首次将自抗扰控制器应用于光电望远镜的伺服系统中,根据自抗扰控制器可以动态补偿系统模型扰动和外部扰动,将作为负载扰动的风阻力矩归为外部扰动,利用扩张观测器对包括风阻力矩的各项扰动进行观测和补偿.该方法能有效地抑制风阻力矩对系统的影响,同时提高伺服系统速度环的响应速度,减小了稳态误差且无超调.仿真结果表明,具有自抗扰控制器的调速系统,当随机风阻力矩在±100N.m之间变化时,系统稳态误差的均值为1.8×10-5rad/s,标准差为9.87×10-4rad/s,最大值约为5.7×10-3rad/s,其抗扰性能明显优于PID调速系统.     

受需求扰动的供应链系统最优跟踪控制

针对动态供应链系统中市场需求扰动引起的牛鞭效应问题,提出一种基于前馈补偿的最优跟踪控制设计方法.首先,针对需求扰动可模型化为线性外系统的情形,引入了一个渐近稳定的期望系统;然后,基于线性二次型性能指标,给出了受需求扰动的供应链系统的前馈反馈最优跟踪控制器设计方法.控制器的反馈增益和前馈增益可分别通过求解Riccati方程和Stein方程得到.仿真结果表明,提出的前馈反馈最优跟踪控制方法能有效抑制需求扰动对供应链系统的影响,改善供应链系统的动态性能,且该方法明显优于经典的最优跟踪控制.     

Precise trajectory tracking of a piezoactuator-driven stage using an adaptive backstepping control scheme

In this paper, an adaptive backstepping control scheme is proposed for precise trajectory tracking of a piezoactuator-driven stage. Differential equations consisting of dynamics of a linear motion system and a hysteresis function are investigated first for describing the dynamics of motion of the piezoactuator-driven stage with hysteresis behavior. Then, to identify the uncertain parameters designed in the differential equations, the Powell method of a numerical optimization technique is used. From the differential equations identified, an equivalent state-space model is developed, then a linear state-space model through a state transformation is established. In the linear state-space model, the hysteresis function is approximated by the first three terms of a Taylor series expansion. Based on the linear state-space model, we developed an adaptive backstepping control for the trajectory tracking. By using the proposed control approach to trajectory tracking of the piezoactuator-driven stage, improvements in the tracking performance, steady-state error, and robustness to disturbance can be obtained. To validate the proposed control scheme, a computer-controlled, single-axis piezoactuator-driven stage with a laser displacement interferometer was set up. Experimental results illustrate the feasibility of the proposed control for practical applications in trajectory tracking.     

Non-Negative Adaptive Mechanism-Based Sliding Mode Control for Parallel Manipulators with Uncertainties

In this paper, a non-negative adaptive mechanism based on an adaptive nonsingular fast terminal sliding mode control strategy is proposed to have finite time and high-speed trajectory tracking for parallel manipulators with the existence of unknown bounded complex uncertainties and external disturbances. The proposed approach is a hybrid scheme of the online non-negative adaptive mechanism, tracking differentiator, and nonsingular fast terminal sliding mode control (NFTSMC). Based on the online non-negative adaptive mechanism, the proposed control can remove the assumption that the uncertainties and disturbances must be bounded for the NFTSMC controllers. The proposed controller has several advantages such as simple structure, easy implementation, rapid response, chattering-free, high precision, robustness, singularity avoidance, and finite-time convergence. Since all control parameters are online updated via tracking differentiator and non-negative adaptive law, the tracking control performance at high-speed motions can be better in real-time requirement and disturbance rejection ability. Finally, simulation results validate the effectiveness of the proposed method.     

扰动跟踪控制系统设计与仿真

在 60 Nm间随机变化的扰动力矩作用于一个实际设备的控制系统时,对其引起的跟踪误差作了仿真分析。并在研究扰动引起的稳态误差、系统结构及和参数之间关系的基础上,设计了控制系统的扰动补偿器。对扰动补偿控制系统进行了仿真,结果表明,扰动补偿控制可以减小或消除风力矩扰动引起的跟踪误差。     

Efficient and robust model predictive control for first swing transient stability of power systems using flexible AC transmission systems devices

A wide area measurement, nonlinear, model predictive control (MPC) approach is introduced to provide first swing stability protection of vulnerable power system transmission lines. The authors consider large disturbance events and focus on the avoidance of first swing angular separation using flexible AC transmission systems (FACTS) devices. The presented control strategy for FACTS devices is designed to be numerically efficient (due to the short MPC horizons) and robust (against complicated separation mechanisms). Simulation studies conducted on a three-machine system illustrate that the proposed MPC approach achieves first swing large disturbance performance that is near optimal and superior to existing transient stability controllers. Moreover, the proposed control approach is demonstrated to improve critical clearance times and to improve transfer capacity in simulation studies on the 39 bus New England system.     

车辆半主动座椅悬架自适应模糊滑模控制

针对含有人体模型的五自由度半主动座椅悬架系统,设计一种基于趋近率的滑模控制器。通过引入自适应控制算法,对系统模型简化过程中产生的扰动及外界干扰进行估计,并在简化模型的基础上采用模糊算法,对滑模控制中趋近速率参数进行优化,在保证趋近速率的同时,提高系统的鲁棒性;采用双曲正切函数替代切换项中的符号函数使得系统在切换过程中更加连续,有效降低滑模控制中的抖振问题;根据Lyapunov稳定判据证明了系统的鲁棒稳定性。数值仿真表明,采用该控制器的座椅悬架较采用PID控制及被动控制的座椅悬架减振效果得到了明显改善,C级路面上时座椅悬架振动加速度值相较于PID控制与被动控制的座椅悬架分别下降25.1%与57.2%,冲击工况下分别下降16.9%与63.7%,并具有较好的跟踪性能。     

基于工业焊接小车的视觉伺服控制算法研究

针对基于视觉传感器的焊接小车，提出了提高跟踪精度和鲁棒性的视觉伺服控制方法。首先，建立了图像特征的数学模型，并设计了错误数据的检测算法，其次，对于折线焊缝跟踪过程中存在的位置延迟问题，采用了一种自适应视觉伺服控制结构。这种自适应结构在线检测焊缝方向，并能够在焊缝方向发生变化时对控制参数进行相应的调整。针对该控制结构，设计了基于Kalman滤波器的焊缝方向变化检测算法、参考像素坐标调整算法以及预测与实时调整相结合的控制方法。焊缝自动跟踪实验表明所提方法具有较强的鲁棒性和较高的精度。     

Coordinated Control of Sliding Mode and Hamiltonian for PWM Rectifier

Aiming at the PWM rectifier control strategy of sliding mode control,steady state performance weak Hamiltonian control dynamic tracking performance is poor,the coordinated compound control is proposed,the feedback linearization controller and sliding mode controller Hamiltonian system is obtained,and the design of a coordinated control strategy. In order to verify the accuracy of this method,MATLAB/Simulink is used for simulation analysis. The simulation results show that the composite control can achieve the coordinated dynamic rapid tracking and constant DC output and unit power factor operation,and satisfy the control requirements of the rectifier,effectively reducing the disturbance effect on the system. Compared with Hamiltonian control,the proposed method combines the advantages of the two methods,which have the fast tracking performance and excellent steady-state characteristics,and the research prospect is broad.     

红外测角仪抗红外干扰的信息处理方法

简要介绍了反坦克导弹红外测角仪的信息处理系统组成原理,讨论了红外测角仪抗红外干扰的信息处理方法,导弹目标信号的确定要通过真假红外信号的模式识别和航迹判别处理等才能最终确定,同时对由于大气红外衰减造成的红外信号闪烁以及其它干扰造成的导弹目标丢失情况,设计了信号数据溢出处理模块。这些信息处理方法使红外测角仪的抗红外干扰能力明显提高。试验表明,当坦克目标上有一个探照灯时,红外测角仪能正常工作,当横向偏离坦克目标或弹道10m以外有2个红外干扰时,红外测角仪也能正常工作。     

On high-resolution manoeuvres control via trajectory optimization

This research is on a realization of control approach in line with the trajectory optimization for the purpose of dealing with overactuated spacecraft in the process of the high-resolution manoeuvres. The idea behind the research is to realize closed control loops to cope with the rotational angles and the corresponding angular rates, synchronously, to handle the spacecraft manoeuvres. It is to be noted that the traditional techniques may not have sufficient merit to deal with such a complicated process, suitably. The proposed trajectory optimization is designed to provide the three-axis referenced commands, in finite burn, for transferring the aforementioned overactuated spacecraft from the initial orbit to its final outcomes in the orbital transfer process. The outcomes are realized through the variations of the orbital parameters, including the inclination, the eccentricity, the angular momentum, the semi-major axis and so on, in the high-resolution manoeuvres. It aims to get the system under control to guarantee the performance of the three-dimensional rotational angles tracking to be desirable, instantly. The contribution of the research is to make the high-thrust optimization trajectory, which is organized in association with the new configuration of the three-axis attitude control approach, to be applicable to manage the present overactuated spacecraft in the procedure of high-resolution orbital transfer process. The investigated outcomes of the research are efficient and competitive along with the potential materials through a series of experiments, as long as the desirable tracking performance in the three-dimensional space manoeuvres is apparently guaranteed.