Abstract: With this method it is possible to evaluate opposing friction forces occurring after a certain operating time on a mobile object in a guide. The method consists of measuring the variations in the speed of movement of the mobile object, of calculating the theoretical speed of movement without friction, of combining these two results and thereby deducing outside opposing forces through calculation of the acceleration of the mobile object. Particular application to the evaluation of additional friction forces acting on a mobile control cluster assembly in the core of a pressurized water nuclear reactor.

Abstract: With this method it is possible to evaluate opposing friction forces occurring after a certain operating time on a mobile object in a guide.

Abstract: A track device for mounting on a pneumatic tire fitted to the wheel of a vehicle to improve the buoyancy and traction of the vehicle over very soft terrain, the pneumatic tire including a tread surface across the width of the tire, a pair of side walls and an axis of rotation. The track device includes a plurality of bridge-like longitudinal and rigid traction blades having an inside surface made to rest on the tire across the width of the tread surface and a ground engaging outside surface, the traction blades being disposed on the tire in generally closely spaced-apart and parallel relationship to form an endless track. Each traction blade includes an intermediate bridge-like portion made to conform to the general cross-sectional shape of the tire, essentially flat side portions outwardly projecting from either side of the intermediate portion and generally parallel to the axis of rotation of the tire.