Shear cutting heads are standard devices in the domain of energy wood harvesting, that can be easily implemented on hydraulic excavators. In order to increase the operational flexibility of these machines, it could be interesting to be able to separate the lower part and the upper part of standing trees. Currently, the use of shear cutting heads for this application is limited, because it does not exist reliable sensors able to measure the distance between the cutting head and the soil. We present in this paper the development of a range sensor based on microwave radar. Due to the harsh functioning conditions in forest environments, the microwave radar technology is an interesting solution for harvesting applications, and it allows to overcome the limitations of classical optical sensors. The radar has been positioned on a tree harvesting machine, and results obtained in real conditions are presented.

Pour les pays qui possedent de grandes surfaces d’elevage extensif, le suivi et la tracabilite du betail ouvre des perspectives pour etudier le comportement animal dans des experimentations de conduite de pâturage mais aussi pour surveiller les mouvements et les contacts entre les animaux dans un souci de controle sanitaire. C’est dans le cadre du projet europeen OTAG melant une approche de recherche tripartite entre la France, le Canada et des pays du Cone Sud1, qu’a ete mis au point un dispositif de suivi GPS et de tracabilite pour les animaux d’elevage qui respecte les fortes contraintes d’autonomie et de robustesse necessaires a ce type d’application.

Protecting biotopes and maintaining biodiversity are ecological aims highlighted in European policies. Grazing systems which have to adapt to these new constraints require new fencing technologies. Here we present a virtual fence based on an electromagnetic coupling principle. The fence is an insulated wire in loop unrolled on the ground around the animals. An electromagnetic field is created in the wire which is coupled to a device carried by collared animals. When the fence signal is detected by the collar, a behavior algorithm decides the action to apply to the animal to prevent it from crossing the wire. More than 800 days of experiment on 150 cattle of different breed's were carried out in France between 1999 and 2003. Bringing more flexibility in fencing, this new system could lead to more precise management of grazing in protected zones and allows for environmental renovation of wild areas.