SBIR-STTR Award

In the proposed work, we will develop a highly efficient and miniaturized vibration energy harvesting device suitable for use on drive system components of helicopters. The goal is to provide power to run a wireless corrosion hub and sensors (to be developed simultaneously in a separate program). The target power generating capability is 5mW under vibration conditions typical of steady state flight. The size and mass of the system will be miniaturized. Target metrics are 0.0.1mW/gram, and 0.5mW/cc. The harvester will be implemented using our proven strain optimized, resonating cantilever beam with Macro Fiber Composite piezoelectric elements. An integral energy harvesting circuit will be based on one of our two proven circuit designs, our Managed Switching design, or out Capacitive Discharge design. The principle technical challenges will be in minimizing the size and mass of the device while still achieving target power output. This will be achieved by stacking multiple layers of MFC material on the beam, and implementing design features to minimize the beams stiffness. Ensuring long term reliable operation in hostile environments is a second technical challenge. We will accomplish this through careful selection of materials, and by incorporating environmental sealing and overload stops into the enclosure design.

Benefit:
The miniaturization of vibration energy harvesters is important for transition of embedded wireless sensors to the Navys aircraft fleet since the harvester replaces conventional batteries. The advances proposed in this SBIR program will facilitate the development of smaller, more efficient vibration harvesters for critical aircraft structures. Combining a miniaturized vibration harvester with a smart, wireless sensor hub will allow the realization of an extremely versatile structural monitoring system allowing multiple sensors of corrosion, strain, pressure, torque, load, displacement, humidity, and temperature to be used as the application demands. Were currently working with Bell Helicopter and Sikorsky to develop wireless SHM systems for use on Navy helicopters. There are also large potential markets for military and commercial ground vehicles, ships, and heavy equipment.

Keywords:
Sensor, Sensor, corrosion, Wireless, Energy Harvesting, CBM, Scavenging, SHM

A major barrier to the widespread adoption of wireless sensors for structural health monitoring is the requirement to power the network of wireless nodes. Batteries have a limited lifespan, adding significant size, weight, and costs to the wireless sensor network,and may represent a long term environmental problem. Battery maintenance can be eliminated by harvesting energy from the environment. For many structures, strain and vibration energy are prevalent during operation, and these energies can be exploited to allow the realization of maintenance free wireless sensor networks. The design of an optimized energy harvesting system for sensing requires a comprehensive knowledge of the strain and/or vibration energies available in the operational environment. Furthermore, the sensing requirements must be well defined,including the sensor types and number of channels, their burst sample rates, duty cycles, and wireless data communications rates & range. The objective of this proposal is to miniaturize a vibro-mechanical energy harvester for the purpose of powering a dedicated wireless sensor hub. The sensor hub shall be capable of supporting a wired multidrop sensor network, including corrosion, strain, pressure, and vibration sensors.

Keywords:
Gearbox, Wireless Sensor, Vibration Energy Harvester, Magnetic , Piezoelectric,