As a key component of electro-optical systems, a Two-axis Scan mirror AssemblY(TSAY) is usually used for Line-of-Sight(LOS) precision pointing, tracking, scanning, and stabilizing. Therefore, it is necessary for a TSA...As a key component of electro-optical systems, a Two-axis Scan mirror AssemblY(TSAY) is usually used for Line-of-Sight(LOS) precision pointing, tracking, scanning, and stabilizing. Therefore, it is necessary for a TSAY to have a large angular range, high dynamic characteristics, and small mirror surface distortion. Furthermore, vibration from carriers of electro-optical systems, such as spacecraft and airplanes, is inevitable, so it is critical to guarantee the control accuracy of a TSAY under vibration. In this paper, a TSAY prototype is designed and developed. To increase the control bandwidth, structural topology optimization is applied to the TSAY’s elliptical mirror to reduce the moment of inertia, meanwhile keeping surface flatness. A flexible hinge is adopted to achieve a large angular range. To suppress the angular perturbation caused by the base linear vibration, an adaptive feedforward loop with base-integrated Micro-Electro-Mechanical System(MEMS) accelerators is constructed to enhance the TSAY’s feedback loop. Simulation and experimental results show that the TSAY prototype’s two-axis mechanical angular ranges are more than ±3.2°, the mirror surface flatness Root Mean Square(RMS) value is better than 0.04 k, and the closed-loop bandwidth is beyond 330 Hz. These are suitable for most applications. Besides, the angular perturbation caused by the base vibration can be suppressed more than 37.7% with the addition of the adaptive feedforward loop.展开更多
This paper presents the design of an experimental battlefield dynamic scanning and staring imaging system based on a fast steering mirror(FSM), which is capable of real-time monitoring of hot targets and wide-area rec...This paper presents the design of an experimental battlefield dynamic scanning and staring imaging system based on a fast steering mirror(FSM), which is capable of real-time monitoring of hot targets and wide-area reconnaissance of hot regions. First,the working principle and working sequence of the FSM are briefly analyzed. The mathematical model of the FSM system is built by modeling its dynamic and electrical properties, and the rationality of the model is validated by means of model identification. Second,the influence of external sources of disturbance such as the carrier and moment on the control precision of the FSM is effectively suppressed by the jointly controlling of proportional integral(PI)and disturbance observer(DOB), thus realizing a high precision and strong robustness control of the FSM system. Then, this paper designs an experimental prototype and introduces a special optical structure to enable the infrared camera to share the FSM with the visible light camera. Finally, the influence of the velocity difference between the mirror of the FSM and the rotating platform on the imaging quality of the system is experimentally analyzed by using the image sharpness evaluation method based on point sharpness. A good dynamic scanning and staring imaging result is achieved when the velocity of these two components correspond.展开更多
We study the feasibility of endoscopic optical Doppler tomography with a micro-electro-mechanical system(MEMS) mirror based probe. The additional phase shifts introduced by the probe are tracked and formulated.The sup...We study the feasibility of endoscopic optical Doppler tomography with a micro-electro-mechanical system(MEMS) mirror based probe. The additional phase shifts introduced by the probe are tracked and formulated.The suppression method of the probe phase shifts is proposed and validated by fluid flow detection experiments.In vivo blood flow detection is also implemented on a hairless mouse. The velocities of the blood flow in two directions are obtained to be-8.1 mm/s and 6.6 mm/s, respectively.展开更多
<div style="text-align:justify;"> In this work, a design of a compact optical MEMS-based lidar scanning system with a large field of view (FOV) and small distortion is presented. The scanning system ap...<div style="text-align:justify;"> In this work, a design of a compact optical MEMS-based lidar scanning system with a large field of view (FOV) and small distortion is presented. The scanning system applies an off-axis structure and the length of the system can be reduced to about 10 cm in an optimized way. Simulation results show that a large FOV is achieved under a uniform scanning scheme. In addition, the spot size less than 20 cm at distance of 100 m is also realized. The optical scanning system can be used for the vehicle-mounted Lidar. </div>展开更多
为了分析某热像仪帧扫描镜在工作状态下的面形变化和产生2000 H z共振的原因,并提供改进设计依据,根据帧扫描镜运动曲线计算了帧扫描镜的扫描角速度和角加速度,用有限元分析软件I-DEA S计算了扫描镜在扫描、加速、减速过程中面型的变化...为了分析某热像仪帧扫描镜在工作状态下的面形变化和产生2000 H z共振的原因,并提供改进设计依据,根据帧扫描镜运动曲线计算了帧扫描镜的扫描角速度和角加速度,用有限元分析软件I-DEA S计算了扫描镜在扫描、加速、减速过程中面型的变化和前10阶固有模态,分析了扫描镜在试验中产生2000 H z共振的原因,并对扫描镜结构进行了改进,重新计算了面型变化和前10阶模态,试验证明消除了共振现象。最后提出了扫描镜设计时应注意动态下的面型变化是否满足要求,以及固有模态要避开驱动力矩中的干扰频率等要点。展开更多
基金the support by the National Natural Science Foundation of China (No. 11672016)
文摘As a key component of electro-optical systems, a Two-axis Scan mirror AssemblY(TSAY) is usually used for Line-of-Sight(LOS) precision pointing, tracking, scanning, and stabilizing. Therefore, it is necessary for a TSAY to have a large angular range, high dynamic characteristics, and small mirror surface distortion. Furthermore, vibration from carriers of electro-optical systems, such as spacecraft and airplanes, is inevitable, so it is critical to guarantee the control accuracy of a TSAY under vibration. In this paper, a TSAY prototype is designed and developed. To increase the control bandwidth, structural topology optimization is applied to the TSAY’s elliptical mirror to reduce the moment of inertia, meanwhile keeping surface flatness. A flexible hinge is adopted to achieve a large angular range. To suppress the angular perturbation caused by the base linear vibration, an adaptive feedforward loop with base-integrated Micro-Electro-Mechanical System(MEMS) accelerators is constructed to enhance the TSAY’s feedback loop. Simulation and experimental results show that the TSAY prototype’s two-axis mechanical angular ranges are more than ±3.2°, the mirror surface flatness Root Mean Square(RMS) value is better than 0.04 k, and the closed-loop bandwidth is beyond 330 Hz. These are suitable for most applications. Besides, the angular perturbation caused by the base vibration can be suppressed more than 37.7% with the addition of the adaptive feedforward loop.
基金supported by the National Defense Pre-research Project of China during the 12th Five-year Plan Period(4040570201)Innovation Project of Military Academy(ZYX14060014)
文摘This paper presents the design of an experimental battlefield dynamic scanning and staring imaging system based on a fast steering mirror(FSM), which is capable of real-time monitoring of hot targets and wide-area reconnaissance of hot regions. First,the working principle and working sequence of the FSM are briefly analyzed. The mathematical model of the FSM system is built by modeling its dynamic and electrical properties, and the rationality of the model is validated by means of model identification. Second,the influence of external sources of disturbance such as the carrier and moment on the control precision of the FSM is effectively suppressed by the jointly controlling of proportional integral(PI)and disturbance observer(DOB), thus realizing a high precision and strong robustness control of the FSM system. Then, this paper designs an experimental prototype and introduces a special optical structure to enable the infrared camera to share the FSM with the visible light camera. Finally, the influence of the velocity difference between the mirror of the FSM and the rotating platform on the imaging quality of the system is experimentally analyzed by using the image sharpness evaluation method based on point sharpness. A good dynamic scanning and staring imaging result is achieved when the velocity of these two components correspond.
基金Supported by the National Natural Science Foundation of China under Grant No 61705199the Natural Science Foundation of Henan Province under Grant No 162300410317+2 种基金the Henan Science and Technology Project under Grant Nos 162102310576and 172102210542the Zhengzhou Science and Technology Project under Grant No 153PKJGG125the US National Science Foundation under Grant No 1002209
文摘We study the feasibility of endoscopic optical Doppler tomography with a micro-electro-mechanical system(MEMS) mirror based probe. The additional phase shifts introduced by the probe are tracked and formulated.The suppression method of the probe phase shifts is proposed and validated by fluid flow detection experiments.In vivo blood flow detection is also implemented on a hairless mouse. The velocities of the blood flow in two directions are obtained to be-8.1 mm/s and 6.6 mm/s, respectively.
文摘<div style="text-align:justify;"> In this work, a design of a compact optical MEMS-based lidar scanning system with a large field of view (FOV) and small distortion is presented. The scanning system applies an off-axis structure and the length of the system can be reduced to about 10 cm in an optimized way. Simulation results show that a large FOV is achieved under a uniform scanning scheme. In addition, the spot size less than 20 cm at distance of 100 m is also realized. The optical scanning system can be used for the vehicle-mounted Lidar. </div>
文摘为了分析某热像仪帧扫描镜在工作状态下的面形变化和产生2000 H z共振的原因,并提供改进设计依据,根据帧扫描镜运动曲线计算了帧扫描镜的扫描角速度和角加速度,用有限元分析软件I-DEA S计算了扫描镜在扫描、加速、减速过程中面型的变化和前10阶固有模态,分析了扫描镜在试验中产生2000 H z共振的原因,并对扫描镜结构进行了改进,重新计算了面型变化和前10阶模态,试验证明消除了共振现象。最后提出了扫描镜设计时应注意动态下的面型变化是否满足要求,以及固有模态要避开驱动力矩中的干扰频率等要点。
基金The Program for the New Century Excellent Talents in University,Ministry of Education of China(No.NCET-10-0075)the National Natural Science Foundation of China(No.50805123
