or other parts has a pair of mutually rotated gimbals attached to the outer shell or element for applying rotational displacements about two axes and a linear input attached to the inner element to apply a force along another axis each axis input is effected by a linear actuator and the gimbal inputs are specially designed to assure accurate independent control without parasitic motion between the inputs force and displacement transducers monitor each axis to provide feedback signals to control circuits a heat chamber including the gimbal assembly has hot air applied from an external source through a hollow gimbal hub to hold the test specimen at a desired temperature application_number US 15860588 A description the invention in its preferred form is directed to a testing machine for bushings of the type comprising a hollow cylindrical elastomer bounded by inner and outer steel sleeves it will however be apparent that parts other than bushings can be tested on this machine for example ball joints or other components with inner and outer elements subject to linear and rotational forces or displacements about different axes can also be tested the testing machine as applied to bushings has a fixture which separately clamps the inner and outer sleeves and three independently controlled actuators apply forces to the sleeves on three axes of motion linear motion is applied along one axis and rotary or oscillating motion is applied about two mutually perpendicular axes the motion or.