深空环境音圈驱动大范围AFM高速成像技术研究

The application of the atomic force microscope(AFM) in the deep space exploration is of great significance to truly and accurately understand the microscopic morphology and the properties of space materials for human. The traditional AFM is generally actuated by piezoelectric ceramics tube, which results in low imaging rate and small scanning range. Therefore, it cannot meet the demand of the deep space exploration. Based on our previous research, we will focus on the research of the high-speed imaging technology of wide-range AFM. The project can be divided into two parts. 1) Research on the wide-range scanner actuated by voice coil motors to make the high-speed wide-range positioning come true. It includes the study of the hysteresis model and the nonlinear correction method of the voice coil motor, the mechanical structure design of the flexure-based scanning platform with wide range, and the design of the hybrid control and spiral scanning algorithm of the voice coil motor. 2) Research on the self-adaptive control of the high-speed AFM to realize the high-speed and high-precision acquirement and processing of signals, which includes the design of the self-adaptive high-speed digital frequency modulation algorithm and the high-speed amplitude acquisition algorithm with high resolution and the self-exciting oscillation circuit to realize the controllable oscillation of the cantilever with a small amplitude, the study of the self-adjusting mechanism of AFMs’ scanning speed, and the research on the self-adaptive mechanism of imaging parameters based on the on-line identification technique. Ultimately, we will master the imaging technology of the high-speed, wide-range, and intelligent AFM, which will promote the deep space exploration of China.

将原子力显微镜（AFM）应用于深空探测对人类真实、准确了解太空物质的微观形貌及性质具有重要意义。传统的原子力显微镜采用压电陶瓷管作为驱动器，扫描范围小且速率慢，无法满足深空环境下大范围、快速成像的要求。本项目将基于已掌握的技术，开展原子力显微镜音圈驱动大范围低电压高速成像技术研究。开展音圈驱动扫描器研究，实现深空环境下扫描平台的高速大范围定位：音圈电机迟滞模型及其非线性校正方法的研究，大范围柔性支承平台机械结构的设计，音圈电机混合控制方法及螺旋扫描方式的研究；开展AFM高速成像自适应控制技术研究，实现信号的高速获取及处理：设计快速自适应数字频率解调算法及探针振动信号快速高精度提取算法，设计探针振幅稳定可控自激励电路；设计仪器扫描速度自整定机制、采用在线辨识技术实现测量参数自设定。最终形成具有自主知识产权的大范围高速智能化原子力显微镜成像技术，提升我国深空物质探测水平。

将原子力显微镜（AFM）应用于深空探测对人类真实、准确了解太空物质的微观形貌及性质具有重要意义。传统的AFM采用压电陶瓷管作为驱动器，扫描范围小且速率慢，无法满足深空环境下大范围、快速成像的要求。.本项目基于已掌握的技术，进行了音圈驱动大范围AFM高速成像技术研究：基于NARX神经网络和传递函数建立音圈电机率相关迟滞模型，根据该模型建立逆模型，通过前馈控制，实现对音圈电机迟滞非线性的补偿；基于柔性结构设计音圈驱动大范围高带宽扫描器，实现低压驱动及毫米级范围的高精度扫描。基于卡尔曼滤波技术设计频率调制AFM探针快速幅频解调算法，简化了解调电路结构的同时加快了系统响应速度。基于迭代学习控制技术实现PID控制器参数自整定,设计AFM扫描速度自适应算法实现仪器根据样品形貌自动调整扫描速度，基于贝叶斯压缩感知技术实现AFM欠采样及图像快速重建,设计变角速度螺旋式扫描算法提高扫描速率。通过以上技术的实施，有效地提高了仪器的扫描范围、速度和智能化水平。.本项目在深空环境频率调制原子力显微镜大范围、快速、智能化成像等领域均取得了相应的研究成果，发表学术论文23篇，其中SCI论文15篇，参加国际/国内学术会议/学术研讨总计约20人次，申请/授权国家发明专利3项，形成具有自主知识产权的大范围高速智能化原子力显微镜成像技术。