SPONSOR: MICHIGAN SPACE GRANT CONSORTIUM
PI: Qingli Dai
The safety and reliability of space structures such as airplane wings and helicopters can be significantly decreased because of turbulence and vibrations. All frames and elements have a natural frequency associated with their dimensions and material properties. When these natural frequencies resonate in an element, superposition can cause the propagating waves to increase stresses and forces on the elements. Vibrations in space-structures will cause fatigue on the materials, decrease fuel-efficiency by increasing drag forces, and lead to the operation safety issues or even catastrophic failure of aerospace structures.
The vibrations can be decreased by the use of a trailing edge flap actuator. The trailing edge flap actuator is essentially a flap on an aircraft wing that will change the natural frequency of the element to prevent large vibrations. Changing the geometry of an aircraft wing will cause a different distribution of forces, and therefore can counteract the forces that create the vibrations. CmTent designs for controlling and operating the flap require the use of hydraulics; however, the hydraulic systems are susceptible to pressure differentials in the atmosphere. Therefore, research is being conducted on newer technologies that utilize piezoelectric flap actuators and/or shape-memory alloys to activate the flaps.