Knee joint for anthropomorphic dummy

Claim 1

A knee joint for an anthropomorphic dummy comprising, in combination: a femur member having a cylindrical pivot bearing; a tibia member having a cylindrical socket adapted to receive the femur pivot bearing therein, the radius of the socket being greater than that of the pivot bearing to allow translational movement therebetween; resilient locating means between the pivot bearing and socket tending to restore the same to a substantially coaxial relationship; a plurality of pivotably linked arms defining a parallelogram with four apexes, a first and second of the arms being parallel and further being connected pivotably, each at one of two adjacent apexes, to the tibia member and being further connected pivotably, each at one of the other two apexes to a third arm, the third arm being centrally, pivotably supported by the femur coaxially with the pivot bearing, the plurality of arms thereby being effective to link the femur and tibia members, allow rotation and shearing translation therebetween in a direction substantially perpendicular to the tibia member, prevent translation therebetween in a direction not substantially perpendicular to the tibia member and indicate, through movement of the first or second arm relative to the tibia member, the amount of shearing translation.