Abstract: According to at least one exemplary embodiment, a variable preload device is disclosed. The variable preload device may include at least two annular end members, each annular member adapted to receive a shaft therein, and a plurality of plates axially extending between the annular end members and hingedly coupled thereto. The plurality of plates may be adapted to bend inward so as to impart an hourglass configuration to the variable preload device when the variable preload device is at rest and to bend outward in proportion to increased rotational speed provided to the variable preload device. Furthermore, the axial distance between the annular end members may varies in proportion to the rotational speed provided to the variable preload device.

Abstract: An apparatus for performing environmental testing on a device, and a method for controlling the atmospheric conditions of the apparatus are disclosed. The apparatus includes a test chamber and at least one air heater for controlling air temperature within the test chamber. The apparatus further includes at least one liquid heater for disposed in connection with a liquid reservoir for heating the liquid to control humidity within the test chamber. Finally, the apparatus includes first and second controllers for controlling the at least one air heater and the at least one liquid heater, and thus for controlling the temperature and humidity within the test chamber.