【作者】 谢机有；

【导师】 王省书；

【作者基本信息】 国防科学技术大学 ， 光学工程， 2011， 硕士

【摘要】 针对课题组研制新一代成像激光雷达的实际需求,论文从提高多面转镜式激光扫描器的位置精度、速度稳定性以及延长系统寿命的角度对转镜式扫描技术进行了研究。论文首先设计了整个扫描器的总体结构,分析了镜面形变、速度稳定性等因素对扫描激光脚点位置误差的影响,提出了系统性能指标。根据设计需求选择了无刷直流电机作为系统驱动部件,光栅编码器作为系统位置测量元件,并确定了各自的型号和技术参数。利用SolidWorks完成了转镜的建模和系统其余部件的机械设计并进行了力学分析。针对转镜的具体结构,利用刚体平衡条件,重点对转镜进行了静平衡和动平衡设计和优化。提出了一种基于SolidWorks的转镜平衡分析方法,该方法利用SolidWorks的质量评估功能得到转镜的质心坐标和中心惯性主轴与旋转轴的夹角以此作为转镜动平衡性能评价指标。提出了一种基于SolidWorks Simulation的转镜动平衡仿真方法,上述方法普遍适用于一般刚性转子。利用ANSYS对转镜进行了形变仿真分析,结果表明:3600rpm条件下,转镜形变小于30nm,形变角小于0.1",由此引起的10m远处激光脚点位置误差小于0.01mm。设计了无刷直流电机驱动电路,电路以无刷直流电机专用控制芯片Si9979Cs为核心,以三片Si9936DY组成三相MOSFET桥。设计了光耦隔离电路、电源电路等其它外围电路和保护电路。实验结果表明:论文设计的驱动电路工作稳定可靠,能有效驱动Maxon EC-max 40 283867型无刷直流电机。选择了基于经典控制理论的增量式数字PID作为系统的控制方法。利用C8051F120单片机和FPGA组成的控制电路,搭建了由上位机、控制电路、驱动电路和转镜式扫描器等组成的实验系统。实验结果表明:论文采用的控制方法能有效的进行速度调节和控制,转镜能在预定速度稳定运行,速度误差的标准差为10^-5量级。更多还原

【Abstract】 According to the need of designing a new generation imaging ladar, the key technologies of scanning rotating mirror used on imaging ladar are researched in this dissertation for improving the location accuracy, speed stability and protracting the system life.The overall structure of the scanner is designed first. The influence of deformation and speed stability on laser’s point location error is analyzed and the performance index is proposed. According to the design requirements, a brushless DC motor is selected to drive the system and a grating angular encorder is chosen to measure the location. The model of the rotating mirror and other components are completed using SolidWorks for mechanical analysis.According to the specific structure of the rotating mirror, static balance and dynamic balance are designed and optimized using rigid body equilibrium. A balance analysis method of rotating mirror is proposed based on SolidWorks, Which utilizes the quality assessment function of SolidWorks to get the centroid coordinates and the angle between rotation axis and center inertia main axis as the criterion of dynamic balance. A method of dynamic balance simulation of rotating mirror based on SolidWorks Simulation is proposed, and these methods generally applicable to the universal rigid rotor. The deformation of the rotating mirror is simulated and analyzed using ANSYS. The research results indicate that: when the velocity is 3600rpm, the deformation is less than 30nm, and the deformation angle is less than 0.1", the laser point’s location error is less than 0.01mm far away from 10m.A brushless DC motor drive circuit is designed, which utilizes a brushless DC motor control chip Si9979Cs as it’s core, and the three-phase MOSFET bridge is composed of three piece of Si9936DYs. The opto-isolation circuit, power supply circuit, and other peripheral circuits and protection circuits are also designed. The results show that the drive circuit is stable and reliable, and can effectively drive Maxon EC-max 40 283867 type brushless DC motor.Incremental digital PID based on the classical control theory is selected to control the system. The control circuit is composed of C8051F120 MCU and FPGA. The experimental system is built by a host computer, the control circuit, drive circuit and the rotating mirror scanner. The results show that the control method can regulate and control the speed effectively. The rotating mirror can operate stably at a predetermined speed. Standard deviation of speed error is about 10^-5.更多还原