ANIMAL ACTIVITY MEASURED BY INFRARED DETECTORS

A novel activity sensing system has been developed for measuring activity (movements) of domestic animals, The system is based on passive infrared detectors (PID) and a specially designed analogue signal processing interface, The principle is suitable for monitoring the total animal activity in a group of animals in areas up to approximately 60 m(2) using one sensor, The resulting analogue signal, which can be fed into a datalogging system and processed by a computer, is proportional to the surface temperature and velocity of a moving object (animal). The spatial sensitivity at different distances depends on the orientation of the sensor and the selected lens. The sensing uniformity of a commercial detector has been improved by partly covering the lens with strips. (C) 1995 Silsoe Research Institute