A tester includes a manipulator (200) attached to a test head (1) for testing semiconductor devices having a range of motion in mutiple degrees of freedom. Vertical (500) and horizontal (600) bearing assemblies, an expansion joint (400), a swing arm (40), a tumble assembly (700) coupled by a rotary bearing assembly (300) to the swing arm provide for lateral movement of the test head in three dimensions as well as angular movement of the test head in horizontal, tumble or twist rotations.