A research fellow at the University of Sydney in Australia has developed a field-widened pinhole camera for the guidance and stabilization of miniature unmanned aerial vehicles with wingspans of tens of centimeters.A compact pinhole camera for the guidance and stabilization of miniature unmanned aerial vehicles has a field of view of approximately 165°. It produces data that indicate translational and rotational motion in three dimensions in low-light conditions. Courtesy of Christel-Loic Tisse, University of Sydney.Christel-Loic Tisse adopted a top-down design approach in the work, allowing a consideration of egomotion data processing methodology to determine how data should be acquired. Judging that the best approach would be to employ an imaging system with a single viewpoint and a wide field of view, he rejected solutions that could be expected to remain outside the weight limits of a miniature drone or that could not produce the nearly hemispherical images that yield indicators of motion even when confronted with high noise levels.He thus settled on a pinhole camera design. Presuming that the camera’s sensor would be a CMOS device because it would demand less power and offer more opportunity for integration with signal processing electronics than a CCD imager, he determined that the best results would be had from the addition of a planoconvex lens to the far side of the pinhole relative to the sensor and a hemispherical lens to the near side.Tisse constructed a prototype using a 510 × 492-pixel CMOS sensor from OmniVision Technologies Inc. of Sunnyvale, Calif., lenses of LaSFN and BK 7 glass, and a 500-µm-wide pinhole in blackened stainless steel. The mass of the optical system (pinhole and lenses) was approximately 0.2 g. The resulting camera offered a field of view of approximately 165° and produced data that indicated translational and rotational motion in three dimensions in low-light conditions.Although the prototype displayed a slow response that would require the addition of corrective mechanisms, Tisse considers the results promising and suggests that the performance of control systems incorporating pinhole cameras be investigated.