Recording of dairy cows behaviour with wireless accelerometers

The daily behaviour of dairy cows reflects the health and well-being status. The behaviour can be monitored with accelerometers (used as a tilt sensor to measure the angle) in a wireless sensor network. The angle of a leg reflects the lying or standing behaviour, the angle of the head might reflect the eating behaviour. An experiment was carried out at an experimental farm during 50 days. Six cows were equipped with two 2D accelerometers, one attached to the neck and one attached to the right hind leg. The accelerometers were attached to wireless sensor nodes. The acceleration of the neck and leg was recorded every halve minute (average of seven measurements with 1 Hz measuring frequency). Based on calibration measurements, the acceleration of the leg and the neck were both transformed to the angle. A cow was standing when the angle of the leg was more than 45°, otherwise lying. The method to transform the acceleration to angle and behaviour appears to be appropriate, it is possible to monitor the cow's behaviour with a wireless sensor network equipped with accelerometers.