Abstract: A six degree-of-freedom optical tracker system includes LEDs that are mounted on a structure, and are each configured to emit light. An LED controller is coupled to the LEDs and supplies drive current to each of the LEDs in a manner that causes the LEDs to sequentially and individually emit light. A single position sensing device that is spaced apart from each of the LEDs receives the light emitted from each of the LEDs and supplies position data for each LED. A processor receives the position data and determines the position and orientation of the structure relative to the single position sensing device.

Abstract: A six degree-of-freedom optical tracker system includes LEDs that are mounted on a structure, and are each configured to emit light. An LED controller is coupled to the LEDs and supplies drive current to each of the LEDs in a manner that causes the LEDs to sequentially and individually emit light. A single position sensing device that is spaced apart from each of the LEDs receives the light emitted from each of the LEDs and supplies position data for each LED. A processor receives the position data and determines the position and orientation of the structure relative to the single position sensing device.

Abstract: In some examples, a system configured to remove at least some air and other gases that are dissolved in fuel prior to introducing the fuel into a closed fuel system, such as a closed fuel system of an unmanned aerial vehicle. The system includes a vacuum chamber configured to contain a fuel, a vacuum source attached lo the vacuum chamber and configured to draw a vacuum on a headspace over the fuel in the vacuum chamber, and a fuel pump configured to pump the fuel from the vacuum chamber into a closed fuel container without introducing air into the closed fuel container. In some examples, the pump introduces a fuel substantially free of dissolved gases into the closed fuel system.