基于直接光学角度反馈和滑模控制的单镜面二维压电激光扫描器研究

Laser scanner is a device which can precisely control the direction of laser beam. As a key technology, laser scanner plays an important role in modern sophisticated industrial production and scientific research, such as precise industrial processing, high energy laser system, optical communication system, imaging system and so on. Current piezoelectric laser scanners lack of methods to directly detect the reflection angle of the laser beam. Moreover, traditional control method for piezoelectric system usually employs hysteresis modeling, of which the model is very complex. It is hard to identify the parameter of the model and to design the controller. To solve the above problems, this project proposes a piezoelectric laser scanner which employs a position sensitive detector to directly detect the optical reflection angle and applies a sliding mode control method without hysteresis modeling. The combination of improvement of mechanical structure and control method can simplify the controller structure and enhance accuracy and stability. Based on the research of this project, a single-mirror two-dimensional piezoelectric laser scanner with the advantages of compact structure, high precision, simple driving and control system and easily integrating to application, which can provide high-precision laser beam control for microscopic imaging, space laser communications, semiconductor precision machining and shows important research significance and broad market prospects.

激光扫描器是一种能够精确控制激光束指向的器件。高精密的激光定位技术作为关键技术之一，在近代尖端工业生产和科学研究中占据非常重要的地位，如高精度工业加工、高能激光系统、激光通信系统，成像系统等。现有的压电激光扫描器缺乏对激光束指向角度直接探测和反馈的方案，且基于迟滞建模和前馈补偿的控制方案存在模型复杂、参数辨识困难和控制器难以设计的缺点。针对这些问题，本项目提出了采用位敏探测器作为探测核心、结合特定的光路设计实现压电扫描器激光束指向角度的直接反馈方案，基于这一原理进行不需要迟滞建模的滑模控制方案研究，可以简化控制器设计、提升控制精度和稳定性。通过本项目的研究，将提供一种基于直接光学角度反馈的单镜面二维激光扫描器，具有结构小巧紧凑、控制精度高、驱动控制系统简单、容易与应用场景集成等优点，可以在显微成像，空间激光通讯，半导体精密加工等领域提供光束指向控制，具有重要的研究意义和广阔的市场前景。

激光扫描器是一种能够精确控制激光束指向的器件。高精密的激光定位技术作为关键技术之一，在近代尖端工业生产和科学研究中占据非常重要的地位，如高精度工业加工、高能激光系统、激光通信系统，成像系统等。现有的压电激光扫描器缺乏对激光束指向角度直接探测和反馈的方案，且基于迟滞建模和前馈补偿的控制方案存在模型复杂、参数辨识困难和控制器难以设计的缺点。针对这些问题，本项目完成了基于直接光学角度反馈和滑模控制的单镜面二维压电激光扫描器机械、光学、电路和控制系统的设计和调试，在机械结构方面，详细研究了从压电驱动器结构到二维偏转结构的仿真和设计，选择了最优化的设计实现扫描器扫描角度和动态响应的统一；在光学结构方面设计了合理的光源、光路和探测器，实现扫描器扫描角度的直接光学反馈；在电路系统方面，对扫描器驱动电路，PSD反馈电路，控制电路进行设计和调试；在控制算法方面，采用滑模控制算法实现对扫描器高精度控制；经过测试，所研制的激光扫描器两轴扫描角度超过15mrad，分辨率超过2urad，三角波和正弦波跟踪误差小于1%。