Figure 1: BioTRACKER being tested with a video camera. The pictures were used to evaluate pointing accuracy and sun-tracking software.BioTRACKER is a high precision pointing platform for radiometers. It allows radiometers to track the Sun, observe the water surface, and conduct sky scans in support of atmospheric optics studies. In Figure 1, a video camera with a telephoto lens is mounted to BioTRACKER to test the system's performance and control software.

Figure 2 shows a screen shot of the control software when tracking the solar disk. BioTRACKER was designed to include sun photometry capability and have a built-in camera to verify correct solar tracking.

Figure 2: Screen shot of BioTRACKER software. The left side shows a image of the Sun recorded by the video camera mounted on the tracker. The Sun's center, as determined by the software, is indicated by a red cross. The graphs on the right side show the variation of the Sun's center within the frame of the video image during a full day of observation. The resulting functions can be used to accurately position the tracker towards the Sun's center, and to correct for alignment (e.g.,leveling) errors of the system.