【作者】 姬伟；

【导师】 李奇；

【作者基本信息】 东南大学 ， 控制理论与控制工程， 2006， 博士

【摘要】 陀螺稳定跟踪平台广泛应用于弹箭制导、机载、舰载、车载武器等军事领域和空间遥感探测、公安消防、环境监测等民用领域。为了实现运动载体上光电跟踪设备的视轴稳定以保证对机动目标的精确瞄准跟踪,本论文在研制一套新型四轴陀螺稳定光电跟踪转台模拟装置的基础上,针对陀螺稳定光电跟踪系统中的视轴稳定控制、陀螺零漂信号分析与处理、目标状态滤波和预测以及跟踪控制等关键技术进行了理论研究和实验验证。论文主要研究成果包括:1设计研制了一套集载体运动姿态和负载平台运动姿态于一体的新型多功能精密四轴陀螺稳定光电跟踪模拟转台装置。四轴转台中底座摇摆台用于模拟载体运动干扰姿态,负载陀螺稳定台用来模拟光电跟踪系统在载体上的偏航和俯仰姿态。稳定跟踪平台采用力矩电机直接驱动,以光纤陀螺(FOG)作为惯性速率敏感元件构成视轴稳定内回路,以光电编码器或CCD电视跟踪器分别作为位置反馈和目标偏差检测反馈元件组成跟踪回路,采用高速DSP运动控制模块为核心建立了具有开放式结构、标准模块化的多功能转台串级伺服控制系统。2针对光纤陀螺输出信号漂移误差和噪声对视轴稳定回路的影响,提出了采用Allan方差法对光纤陀螺零漂信号进行时域分析方法。根据光纤陀螺信号漂移和噪声的Allan方差与功率谱密度(PSD)关系,在Allan标准差模型的基础上采用最小二乘法(LSM)进行样本数据拟和,有效地分离和辨识出了光纤陀螺零漂信号中的各项误差源随机误差系数和误差贡献大小。在此基础上,研究了三种直接对陀螺输出信号滤波处理的方法:滑动滤波、FLP自适应滤波、小波变换阈值滤波。对陀螺数据测试和统计分析结果表明,小波变换滤波的去噪效果优于其它方法。3针对视轴稳定回路单速度环控制结构缺点,提出了一种采用直流测速机为电机转速测量反馈元件构成模拟速度内环,利用陀螺的“空间测速机”功能组成数字稳定外环的视轴稳定系统双速度闭环串级控制结构。从系统抗干扰性、鲁棒性等方面与单速度环控制进行了理论分析和比较,仿真及实验效果显示该控制结构能够将速度稳定环的抗摩擦力矩干扰功能和隔离外部载体扰动功能分开设计实现,控制性能优于单速度环控制。4针对视轴稳定系统中机械谐振、力矩耦合负载变化及电气参数波动等非线性不确定因素的影响以及系统特殊环境的应用要求,提出了一种基于滞环特性切换条件的视轴稳定自适应模糊PID复合控制策略。所提出的自适应模糊控制器采用模糊控制保证系统的快速动态响应,设计的模糊控制规则和参数的在线自适应调整机制来满足系统在不同状态下的控制要求;采用变速积分PID控制抑制执行电机饱和和克服模糊控制固有的精度“盲区”;提出具有滞环特性的区间切换来解决单点切换所造成的频繁抖动。另外,引入非线性加速度阻尼补偿来克服系统运行中的低速“跳动”现象。实验结果显示该方法达到了更高的控制精度,有效地解决了系统响应快速平稳性和高稳定精度的矛盾。更多还原

【Abstract】 The gyro stabilized and tracking platform has developed rapidly and has been used widely in the military area and civil area such as missile seeker, airborne opto-electronic(O-E) reconnaissance, fire protection, surveillance and control of environment etc. In order to improve line of sight(LOS) stabilization precision of the opto-electronic tracking device and pinpoint the maneuvering target, we do some researches about the essential technologies in the opto-electronic automatic target tracking system. These technologies include simulation turntable design, LOS stabilized control, fiber optic gyro(FOG) signal analysis and processing, target state filtering and prediction, and tracking control methods et al. The principal contributions of this dissertation are summed as follows:1 A set of new-style four-axis precision stabilized tracking turntable, which is comprised of a two-axis vibrate turntable and a two-axis payload stabilized platform, has been developed for simulating attitude motions of TV missile seeker and airborne opto-electronic tracking system. The vibrate turntable used to simulate carrier’s motions, is a two-degree-of-freedom (2DOF) instability gimbal. While, the payload platform is a 2DOF stabilized gimbal simulating azimuth and pitch attitude. The gimbal was driven directly by DC torque motor without middle driver. A compound cascade control structure based on DSP module using the charge coupled device(CCD) camera or O-E encoder to constitute the position closed-loop, and using the FOG to constitute the rate stabilization closed-loop is put forward. Testing results achieve the technical indices and precision requirement.2 The properties of the FOG signal random drift are detected with the Allan variance method. By the relation between the Allan variance of signal noise and power spectrum density (PSD), the sources of some kinds of noise and its properties are analyzed and calculated using fitting algorithm in the least square method(LSM). According to the characteristics of the gyro stabilized platform system, the moving filter, the forward linear prediction(FLP) adaptive filter and the threshold-value filter based on wavelet transform are used to de-noise the FOG signal. The result of testing and statistic analyzing for FOG signal indicate that the Allan variance means is successful in separating the main random error source of signal noise and the advantages of the wavelet threshold-value filter is verified.3 Considering the shortcomings of single rate-loop servo control composed of rate gyro for LOS stabilization of opto-electronic tracking system, a dual rate-loop cascade control structure using the DC tachometer to constitute the analog inner loop, and using the rate gyro to constitute the digital outer loop is presented. The functions of rejecting friction disturbance and insulating carrier turbulence are designed respectively. The system performance for disturbances rejection and robustness are analyzed and compared with single rate-loop servo更多还原