SBIR-STTR Award

There exists a large need in the fluid mechanics community for waterproof micro shear stress sensors. The United Micromachines MEMS hot-film shear-stress sensor with underlying vacuum cavity is the only proven laboratory prototype micro shear stress sensor. In addtion, these sensors can be fabricated on a flexible substrate that can conform to curved test surfaces. With additional effort, the sensor technology can be advanced to the point where the sensor will be a commercially viable product. One of these efforts must be directed in the direction of waterproofing, which will allow the sensors to be used both underwater and in wet (ie raining or very humid) conditions. Initially, United Micromachines will concentrate on developing and testing waterproof coatings for use on the already developed sensor. The testing will concentrate on the waterproofness and pressure effect on sensor performance. In Phase II, United Micromachines will develop the packaging and electronics integration schemes necessary for acceptance by the fluid mechanics community.

There exists a large need in the fluid mechanics community for waterproof, conformal micro shear stress sensors. In Phase I, UM successfully fabricated and tested such sensors. The Phase II effort will integrate waterproof pressure, temperature, and shear stress sensors on the same flexible substrate. In addition, in an effort to produce a generic plug-and-play MEMS flow system, improvements will be made in the electronic control circuitry and the packaging. Finally, extensive validation tests, including both wide-ranging calibration and operation under harsh environmental conditions, will be carried out.

Benefits:
The combined sensor system will give fluid mechanists a full understanding of surface flows. By improving packaging and electronics to the point that the sensing element evolves into a sensor system, UM will produce a flow instrument usable by any scientist or engineer. Aerospace companies such as Boeing and Lockheed Martin, commercial companies such as Kanomax and Schlumberger, government labs such as NASA Langley and NASA Lewis, and military labs such as the Naval Surface Warfare-IHD have all either purchased or are preparing to purchase our MEMS shear stress sensors. The applications range from studying basic physics to studying practical external and internal flows on any sort of moving vehicle.

Keywords:
Mems Hot Film Shear Stress Sensor Waterproof