Micro Locomotion Compensator : an instrument to analyze the orientation behavior of mites and other tiny animals

微运动补偿器是记录和分析螨虫等微小动物定向行为的有力工具。它由一个定位系统和一个由一对电动滑片驱动的舞台，一个带有显微镜头的视频跟踪器和一个个人电脑系统组成。视频跟踪器捕捉到螨虫在舞台上行走的图像，然后定期将其位置数据报告给计算机，将螨虫带回图像中心。因此，在同一空间点上，当螨虫在舞台上自由行走时，可以精确记录1.0 mm / s的极慢运动。本课题的目的是对微运动补偿器进行验证。在这个项目的第一年，我们建立了定位系统，并研究了它是如何工作的。虽然系统的幻灯片使用微型步进电机，但旧的计算机系统已经用于伺服系统，无法在没有振动的情况下驱动它们。因此，我们开发了一种新的控制系统，可以在标准的IBM-PC上以良好的性能驱动幻灯片。在移植到PC系统后，驱动程序对载玻片的控制足够平稳，可以跟踪到尘螨（Dermatophagoides pteronyssinus）以0.2 ~ 0.3 mm / s的速度行走，尘螨的位移几乎是匀速的。当暴露在含有蜘蛛螨聚集信息素的气味空气中时，螨虫停止并改变方向。这些结果将在对虚拟气味源的引导实验中阐明相应的定向机制后发表。

Micro Locomotion Compensator is a powerful instrument to record and analyze the orientation behavior of tiny animals such as mites. It consists of a positioning system with a stage driven by a pair of motorized-slides, a video tracker with a microscopic lens and a personal computer system. The video tracker captures the image of a mite walking on the stage, and then periodically reports its positional data to the computer to bring back the mite to the image center. As a result very slow movement of a mite under 1.0 mm / s can be precisely recorded while it is walking freely on the stage at the same spatial point. The purpose of this project is to prove the micro locomotion compensator.In the first year of this project, we built the positioning system and examined how it works. Although slides of the system use micro-stepping motors, the old computer system, having been used for a servosphere, could not drive them without vibration. Thus we developed a new control system, which can drive the slides in good performance on a standard IBM-PC. After being ported to the PC system, the driver program controlled the slides smoothly enough to trace the mite, Dermatophagoides pteronyssinus, walking at 0.2 - 0.3 mm / s. The displacement of the mite is at almost constant velocity. The mite halted and changed orientation while it is being exposed to pheromonally odored air with geranial : mite's aggregation pheromone. These results will be published after the corresponding orientation mechanism being clarified in a guiding experiment to a virtual odor source.