41 to 50 of 62 Results
Mar 6, 2011
Sherrit, Stewart; Bao, Xiaoqi; Badescu, Mircea; Chang, Zensheu; Geiyer, Daniel; Allen, Phillip; Ostlund, Patrick; Bar-Cohen, Yoseph, 2011, "Planar rotary motor using ultrasonic horns", https://hdl.handle.net/2014/41977, 18th Annual Symposium on Smart Structures and Materials & Nondestructive Evaluation and Health Monitoring, San Diego, CA, March 6-10, 2011., JPL Open Repository
One of the first piezoelectric motor designs with significant rotational speeds was outlined by Barth. This device used extensional piezoelectric elements to produce a time varying force at a distance r from the center of a centrally supported disk. These extensional actuators pr... |
Mar 7, 2010
Bao, Xiaoqi; Bar-Cohen, Yoseph; Scott, James; Sherrit, Stewart; Widholm, Scott; Badescu, Mircea, 2010, "Ultrasonic/sonic drill for high temperature application", https://hdl.handle.net/2014/44789, 12th SPIE Conference - Electroactive Polymer Actuators and Devices(EAPAD), San Diego, California, March 7-11, 2010, JPL Open Repository
Venus is one of the many significant scientific targets for NASA. New rock sampling tools with the ability to be operated at high temperatures of the order of 460°C are required for surface in-situ sampling/analysis missions. Piezoelectric materials such as LiNbO₃ crystals and Bi... |
Mar 7, 2010
Badescu, Mircea; Bao, Xiaoqi; Bar-Cohen, Yoseph; Chang, Zensheu; Kerenyi, Kornel; Lih, Shyh-Shiuh; Sherrit, Stewart; Trease, Brian P.; Widholm, Scott, 2010, "Direct measurement sensor of the boundary shear stress in fluid flow", https://hdl.handle.net/2014/44792, 12th SPIE Conference - Electroactive Polymer Actuators and Devices(EAPAD), San Diego, California, March 7-11, 2010, JPL Open Repository
The flow fields and boundary erosion that are associated with scour at bridge piers are very complex. Direct measurement of the boundary shear stress and boundary pressure fluctuations in experimental scour research has always been a challenge and high spatial resolution and fide... |
Mar 8, 2009
Bao, Xiaoqi; Scott, James; Boudreau, Kate; Bar-Cohen, Yoseph; Sherrit, Stewart; Badescu, Mircea, 2009, "High temperature piezoelectric drill", https://hdl.handle.net/2014/44652, 2009 SPIE Conference on Smart Structures and Materials, San Diego, California, March 8-12, 2009, JPL Open Repository
The current NASA Decadal mission planning effort has identified Venus as a significant scientific target for a surface in-situ sampling/analyzing mission. The Venus environment represents several extremes including high temperature (460°C), high pressure (~9 MPa), and potentially... |
Mar 8, 2009
Bao, Xiaoqi; Bar-Cohen, Yoseph; Sherrit, Stewart; Badescu, Mircea; Louyeh, Sahar, 2009, "Transport powder and liquid samples by surface acoustic waves", https://hdl.handle.net/2014/44651, 2009 SPIE Conference on Smart Structures and Materials, San Diego, California, March 8-12, 2009, JPL Open Repository
Sample transport is an important requirement for In-situ analysis of samples in NASA planetary exploration missions. Tests have shown that powders or liquid drops on a surface can be transported by surface acoustic waves (SAW) that are generated on the surface using interdigital... |
Mar 9, 2008
Bao, Xiaoqi; Biederman, Will; Sherrit, Stewart; Badescu, Mircea; Bar-Cohen, Yoseph; Jones, Christopher; Aldrich, Jack; Chang, Zensheu, 2008, "High-power piezoelectric acoustic-electric power feedthru for metal walls", https://hdl.handle.net/2014/44817, 2008 SPIE Conference on Smart Structures and Materials, San Diego, California, March 9-13, 2008, JPL Open Repository
Piezoelectric acoustic-electric power feed-through devices transfer electric power wirelessly through a solid wall by using acoustic waves. This approach allows for the removal of holes through structures. The technology is applicable to power supply for electric equipment inside... |
Mar 3, 2008
Sherrit, Stewart; Jones, Christopher; Aldrich, Jack; Blodget, Chad; Bao, Xiaoqi; Badescu, Mircea; Bar-Cohen, Yoseph, 2008, "Characterization of piezoelectric stacks for space applications", https://hdl.handle.net/2014/41749, ASCE American Society of Civil Engineers, Earth and Science 2008, Long Beach, California, March 03, 2008., JPL Open Repository
Future NASA missions are increasingly seeking to actuate mechanisms to precision levels in the nanometer range and below. Co-fired multilayer piezoelectric stacks offer the required actuation precision that is needed for such mechanisms. To obtain performance statistics and deter... |
Jun 27, 2006
Bar-Cohen, Yoseph; Sherrit, Stewart; Bao, Xiaoqi; Badescu, Mircea; Aldrich, Jack; Chang, Zensheu, 2006, "Ultrasonic/sonic driller/corer (USDC) as a subsurface sampler and sensors platform for planetary exploration applications", https://hdl.handle.net/2014/39725, 4th International Planetary Probe Workshop, Pasadena, California, June 27-30, 2006., JPL Open Repository
The search for existing or past life in the Universe is one of the most important objectives of NASA’s mission. For this purpose, effective instruments that can sample and conduct in-situ astrobiology analysis are being developed. In support of this objective, a series of novel m... |
Mar 13, 2006
Bao, Xiaoqi; Bar-Cohen, Yoseph; Chang, Zensheu; Sherrit, Stewart; Badescu, Mircea, 2006, "Rock Sampling using the Ultrasonic/Sonic Driller/Corer (USDC) for in-situ planetary exploration", https://hdl.handle.net/2014/38924, 35th Annual Ultrasonic Industry Association (UIA) Symposium, San Diego, California, March 13-14, 2006, JPL Open Repository
No abstract provided |
Feb 27, 2006
Sherrit, Stewart; Doty, Benjamin; Badescu, Mircea; Bao, Xiaoqi; Bar-Cohen, Yoseph; Aldrich, Jack; Chang, Zensheu, 2006, "Studies of acoustic-electric feed-throughs for power transmission through structures.", https://hdl.handle.net/2014/38890, Smart Structures and Materials Symposium, San Diego, California, February 27, 2006., JPL Open Repository
There are numerous engineering design problems where the use of wires to transfer power and communicate data thru the walls of a structure is prohibitive or significantly difficult that it may require a complex design. Using physical feedthroughs in such systems may make them sus... |
