Traditional imaging sensors for computer vision, such as CCD and CMOS arrays, have well-known limitations with regard to detecting objects that are very small in size (that is, a small object image compared to the pixel size), are viewed in a low contrast situation, are moving very fast (with respect to the sensor integration time), or are moving very small distances compared to the sensor pixel spacing. Any one or a combination of these situations can foil a traditional CCD or CMOS sensor array. Alternative sensor designs derived from biological vision systems promise better resolution and object detection in situations such as these. The patent-pending biomimetic vision sensor based on <i>Musca domestica </i>(the common house fly) is capable of reliable object rendition in spite of challenging movement and low contrast conditions. We discuss some interesting early results of comparing the biomimetic sensor to commercial CCD sensors in terms of contrast and motion sensitivity in situations such as those listed above.
Musca domestica, the common house fly, has a simple yet powerful and accessible vision system. Cajal indicated in 1885 the fly's vision system is the same as in the human retina. The house fly has some intriguing vision system features such as fast, analog, parallel operation. Furthermore, it has the ability to detect movement and objects at far better resolution than predicted by photoreceptor spacing, termed hyperacuity. We are investigating the mechanisms behind these features and incorporating them into next generation vision systems. We have developed a prototype sensor that employs a fly inspired arrangement of photodetectors sharing a common lens. The Gaussian shaped acceptance profile of each sensor coupled with overlapped sensor field of views provide the necessary configuration for obtaining hyperacuity data. The sensor is able to detect object movement with far greater resolution than that predicted by photoreceptor spacing. We have exhaustively tested and characterized the sensor to determine its practical resolution limit. Our tests coupled with theory from Bucklew and Saleh (1985) indicate that the limit to the hyperacuity response may only be related to target contrast. We have also implemented an array of these prototype sensors which will allow for two - dimensional position location. These high resolution, low contrast capable sensors are being developed for use as a vision system for an autonomous robot and the next generation of smart wheel chairs. However, they are easily adapted for biological endoscopy, downhole monitoring in oil wells, and other applications.