MFBCE: A Multi-Focal Bionic Compound Eye for Distance Measurement

Abstract: In response to the demand for small-size, high-precision, and real-time target distance measurement in platforms such as autonomous vehicles and drones, this paper investigates the multi-focal bionic compound eye (MFBCE) and its associated distance measurement algorithm. MFBCE was designed integrating multiple lenses with different focal lengths and a CMOS array. Based on this system, a multi-eye distance measurement algorithm based on target detection was proposed. This algorithm extends the application of binocular distance measurement to cameras with different focal lengths, overcoming the limitations of binocular algorithms that are confined to identical cameras. By utilizing multi-scale information captured by the multiple lenses with different focal lengths, the proposed MFBCE achieves enhanced distance measurement accuracy. In the experiment, the least squares method was employed to perform distance measurements for targets within 90 cm to 120 cm, achieving a mean error of 0.56%. With a constant distance-to-baseline ratio, the mean error of the proposed system is approximately 1/5 that of the binocular distance measurement algorithm. The proposed MFBCE demonstrates significant potential for applications in near-range obstacle avoidance, robotic grasping, and assisted driving.