Analog Circuit for Motion Detection Applied to Target Tracking System

Abstract

It is necessary for the system such as the robotics vision and the monitoring camera to detect the motion of the object and recognize the target in real time. However, this is difficult in conventional image processing systems constructed with a charge coupled device (CCD) camera and Neumann-type computer since information processing in this setup is accomplished in a time-sequential way. On the other hand, real-time image processing is easily performed in biological systems constructed with the retina and the brain since information processing is achieved in massively parallel nerve networks which have a hierarchical structure. The biological vision system constructed with the retina and brain can detect the motion of the object in real time and judge the target instantly. The complementary metal oxide semiconductor (CMOS) circuits based on the biological vision system can be expected to realize the high speed processing system since each unit circuit operates in parallel as well as the signal processing of the biological vision system. Many researchers proposed the CMOS circuits for edge detection and motion detection based on the biological vision system (Mead, 1989.; Moini, 1999.; Asai et al., 1999b.; Liu., 2000.; Yamada et al. 2001.; Nishio et al. 2003). These circuits are characterized by the high speed processing. Particularly, there are neurons for tracking the target in the superior colliculus of the brain. The simple target tracking model was proposed based on the signal processing of the brain. The cells for generating the motion signal were introduced at the first stage of the model. The motor for tracking the target was controlled by the motion signal. Recently, analog CMOS circuits were proposed based on the model for tracking the target (Asai et al., 1999a.; Liu et al., 2001.; Moini, 1999). At the first stage of the circuits, analog motion detection CMOS circuits (Asai et al., 1999b.; Liu., 2000.) based on the biological vision system were introduced for generating the motion signal. Recently, we proposed simple analog CMOS circuits for generating the motion signal based on the biological vision system (Nishio et al. 2004.; Nishio et al. 2007). The circuit consists of the half of the number of transistors utilized to previous proposed motion detection circuit, which is used at the first stage of the tracking system. The realization of the simple system for tracking the target can be expected by using our circuits to the first stage of the tracking system. In this study, simple analog CMOS circuit for motion detection was proposed based on the biological vision system. And, I tried to develop the test system for tracking the target based