Our Solution

Abstract

The fuel in the rocket tanks used by NASA operates best at extremely cold temperatures. This cold temperature must be maintained as the rocket lifts off the launch pad and flies through space. A specially-designed thermal blanket uses an aluminum material to keep the fuel tanks cold and protect them from outside heat sources. This blanket, referred to as multilayer insulation (MLI), must maintain very low pressures. When too much gas leaks into the MLI, the fuel gets hotter and does not run effectively. We are designing a pressure sensor that can fit inside of the blanket and measure very low pressures. The sensor is less than a millimeter thick (roughly 1/25th of an inch). It can measure pressure from 10-3 torr to 10-8 torr, which is comparable to the pressure range an object orbiting the earth will experience. This range is considered to be a high vacuum and low pressure. Additionally, the sensor must minimize power consumption and complexity, and it must be able to operate at very low temperatures. Traditional pressure sensors, such as a tire pressure gauge, do not meet these requirements. Our selected design, the cold- cathode gauge, determines the pressure by measuring the amount of charged particles. It begins with a power source that emits electrons, which are negatively charged particles. If there is any pressure in the MLI, the electrons strike the gas molecules, ionizing a percentage of the molecules and providing a measured current. The amount of current then correlates to the pressure in the MLI. Although cold-cathode gauges already exist on the market, we are modifying the design to fit in an extremely small space. Our stakeholders include NASA - Marhsall Space Flight Center and Dr. Guo of the FAMU-FSU College of Engineering.