Tham khảo tài liệu 'mems and microstructures in aerospace applications - robert osiander et al (eds) part 6', kỹ thuật - công nghệ, cơ khí - chế tạo máy phục vụ nhu cầu học tập, nghiên cứu và làm việc hiệu quả | Microtechnologies for Space Systems 119 FIGURE Optical micrograph of the NASA Glenn Research Center Hydrogen Sensor. The device consists of Pd alloy-based resistor and metal-oxide-semiconductor hydrogen sensors. Also incorporated on the chip are a microfabricated heater and temperature sensor for thermal control of the sensor. Source NASA Glenn WWW RT1999 5000 . low mass size and power and can be integrated with miniaturized electronics for signal processing and temperature control. The GRC sensor has also been delivered to the X-33 and X-43 projects and has been baselined for use in the water processing and oxygen generator on the International Space Station. The GRC chip contains two Pd-alloy-based hydrogen sensors. These are a resistor and a metal-oxide-semiconductor device. Also integrated within the chip are a resistive heater and a temperature sensor for controlling the thermal environment of the sensor. MEMS Variable Emittance Control Instrument This MEMS-enabled instrument described in detail elsewhere in this book contains a MEMS shutter array radiator16 that allows tunable control of the radiative properties of spacecraft skins. The project is led by NASA GSFC in partnership with The Johns Hopkins University Applied Physics Laboratory and Sandia National Laboratories. The technology is based on an array of micromachined hinged shutters that can be opened or closed using MEMS comb drives maximum operating voltage 60 V thus presenting a variable emittance surface to the outside environment for the spacecraft. Each shutter is a X mm rectangular surface. The entire shutter array contains a total of 2592 such shutters 36 chips 2006 by Taylor Francis Group LLC 120 MEMS and Microstructures in Aerospace Applications each containing 72 shutters and is assembled within a 9 X 10 X 3 cm enclosure. The instrument is scheduled to fly on a NASA NMP ST5 technology demonstration flight in May 2005. The key factors that .
