There is a growing need for actuator materials that can operate efficiently at extreme temperatures. For example: the James Webb Space Telescope (JWST) requires shape and position control actuators that operate near 30K (-243?C); while NASA?s planed Venus mission requires actuators that operate 460?C (733K). This paper discusses novel piezoelectric single crystal actuators and ultrasonic motors have been developed use in cryogenic environments as low as 20K (-253?C) and new ceramic piezoelectrics that operate at temperatures as high 500?C (773K).

Various single crystal piezoelectric actuators have been developed including stack actuators and flextensional actuators with strokes up to 250 m and resolutions of >1nm at temperatures between 20K and 300K. A wobbling mode cryomotor has also developed with a stroke of 1 to 10mm and a resolution of 20nm in the temperature range of 77K to 300K. The cryogenic actuators presented in this paper feature high precision displacement control, high force output, quick response, low power consumption, and are free of magnetic field interference. These cryogenic actuators are very promising for shape control, precision positioning and force control in various NASA, military and civilian applications such as cryogenic adaptive optics for space telescopes, interferometers in terrestrial planet finder missions, and spectrometers for remote sensing applications.

New actuator materials have also been developed specifically for high-temperature applications. This paper addresses development of this material for an ultrasonic rock drillingcoring- abrading tool to quickly sample Venus surface material for chemical analysis. The key innovation behind this device is a BiScO3-PbTiO3 based piezoelectric ceramic that has been modified to have high resistivity up to 500?C. This material was found to have very good piezoelectric properties to the depoling temperature of 420?C, and at 450?C it functioned as an electrostrictor with an induced piezoelectric coefficient of 450pC/N under a 7kV/cm DC bias.