Vibration test apparatus with an actuator coupled to a reaction mass movable along a linear axis

A method to assemble a testing apparatus for subjecting a device-under-test to oscillating acceleration, the method comprising:

• providing a stage having a mounting surface attachable to the device-under-test;
• and
• coupling an actuator to the stage, the actuator also being coupled to a reaction mass movable along a linear axis;
• providing a first flexure plate comprising a first material and having a first flexure plate middle and a first flexure plate periphery, and attaching the first flexure plate middle to the stage at a first stage end,
• providing a second flexure plate comprising the first material and having a second flexure plate middle and a second flexure plate periphery, and attaching the second flexure plate middle to the stage at a second stage end that opposes the first stage end,
• providing a frame that comprises a second material having a substantially higher coefficient of thermal expansion than the first material,
• cooling the frame, and
• attaching the first flexure plate periphery and the second flexure plate periphery to the frame.