Abstract: A head restraint for animals such as sheep, comprising a support carrying arms for engaging the bridge of the snout and the lower jaw to clamp the jaws in a closed position, arms carried by the support, the arms carrying caps which in use cover the eye of the animal, each cap having a lug which engages a cavity in the skull of the sheep just behind each eye socket.

Abstract: A wrist mechanism suitable for robotic manipulators comprising a first actuator for rotating a first yoke about a first axis, a first crossed shaft carried by the yoke, a second actuator for pivoting the first crossed shaft about a second axis, a second crossed shaft carrying a second yoke, an actuator means for causing rotation of the wrist mechanism about a third axis, highly rigid side plates supporting the first and second crossed shafts in bearings, highly rigid cross members rigidly interconnecting the side plates, and gears for transferring motion between the first and second crossed shafts to allow pivotal movement of an end effector carried by the second yoke in excess of 180.degree. about the second axis, and at least 180.degree. about the third axis, and rotation in excess of 200.degree. about the first axis.