Automated Tracking System for Time Lapse Observation of C. elegans

Model organisms are widely used in biological system investigations. There is a great demand for automatic observation and manipulation of model organisms. In this paper, a tracking system for time-lapse observation of C. elegans is presented. In microscale field, active C. elegans often disappears from the field of microscope version due to the small microscope visual field and the fast speed of C. elegans. Since the depth of focus of the microscope is very small, captured images are often defocused by the movement of C. elegans. In order to overcome the limitation of the microscopic field and limited workspace, we develop an automatic platform with three degrees of freedom that can move in XYZ axis respectively. Our automated tracking system can integrate detection method in X-Y plane with depth evaluation so that the system can achieve auto-focusing and keep the object point always in the center of microscope field. Finally, the system can obtain the current position of expected operating point accurately. Based on target position updated in real-time, the system accomplishes automatic tracking for time-lapse observation of C. elegans.