The device fails this verification because even though the projected total deformation after 168,000 cycles was 2.14 mm (less than the specified value of 40 mm), this was calculated assuming the sum of the individual deformations experienced by each section was equivalent to the total deformation. However, this relationship was not able to be proven as previously stated in the weight support verification study. The device was not able to be tested as a whole due to the size limit of the MTS 810 Material Test System, and the full 168,000 compression cycles were not able to be tested due to limited time and resources. Instead, the device was tested in two separate sections for 1,800 compression cycles each, and the result was an extrapolation of the data collected to estimate how the device would likely behave after the full 168,000 compression cycles.
