视觉伺服控制微机械手的细胞注射研究

Reseach on Cells Micro-Injection Based on Micromanipulator Controled by Vision Serving

细胞注射前,利用伺服控制方程计算的误差矩阵对系统进行标定,减小显微视觉系统和机械手系统间的坐标变换误差。系统误差标定后,利用显微镜聚焦—失焦技术获得深度信息,将细胞、负压管和注射针定位到同一平面上,定位误差达到0.3806#m,再结合光学流跟踪法,轨迹误差由(7,13)像素减小(0,1)像素。误差矩阵的应用非常有利于实时控制。利用纳米驱动平台设计微注射泵和负压泵,通过脉冲控制药液注射量的大小,注射泵理论注射量可以达到3.2皮升,负压泵可以安全地吸附住细胞。实验结果表明,利用上述各种技术,可以方便地完成细胞显微注射。

Before cell injected, the error matrix （EM） is calculated from servoing control equation to calibrate injection system, by which the coordinate transform error between vision system and micromanipulator system is minished. After EM is calculated, depth data is obtained using focus-defocus technology of microscope, this depth data can control probe moving to the plane where capillary and cell are focused, the position precision of probe is confined at 0.3806 μm. Integrating Modified Sum of Squared Difference （SSD） method with servoing control equation, the tracking error of micromanipulator is minished from （7, 13） pixels to （0, 1） pixels. The application of EM is favorable to control online. A injection pump and a adsorption pump drived by nano-plafform are designd, which control capacity of injection by impose, when cell is being injected, injection pump can achieve a theory precision about 3.2 pl, adsorption pump can adsorb cell safely and fix cell stably. Our results on experimentation show that cell can be injected easily when these technologies are used.