A vision-based user authentication system in robot environments by using semi-biometrics and tracking

The user authentication problem is discussed in the context of robot environments. Although authentication is indispensable for useful robot services, the traditional approaches that have been applied in strictly regulated environments cannot be applied as they are when both the robot and humans are freely moving around. In this paper, a new authentication system redesigned to be adapted to robot environments is described. In the proposed system, semi-biometrics and user tracking are incorporated to cope with the limited applicability of traditional authentication techniques. Semi-biometrics indicates a set of features useful for discriminating persons, but only in interested group of persons and in interested frame of time. As a representative semi-biometric feature, body height and color characteristics of the clothes are investigated. Especially, a novel method to measure body height with single camera is proposed. Also by incorporating tracking functionality, the system could maintain the user status information continuously, which is useful not only for recognition but also for finding a designated person.