Analog CMOS velocity sensors

Abstract

A family of analog CMOS velocity sensors is described which measures the velocity of a moving edge by computing its time of travel between adjacent pixels. These sensors are compact, largely invariant to illumination over a wide range, sensitive to edges with very low contrast, and responsive to several orders of magnitude of velocity. Two successful one-dimensional velocity sensors are described in detail; preliminary data on a new two-dimensional velocity sensor is shown. Work in progress to extend these sensors to processing of two-dimensional optical flow is outlined. Keywords: Analog VLSI, CMOS, velocity sensors, motion sensors, optical flow 1. INTRODUCTION Motion is a key component of the visual scene; it is used very effectively by biological organisms from insects up to primates. Motion can be an essential clue to segmenting an object from the background and is very important in determining self-motion. There are clear uses for motion information in robotics, automotive navig...