61 to 70 of 141 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 6, 2011
Bar-Cohen, Yoseph, 2011, "Directions for development of the field of electroactive polymer (EAP)", https://hdl.handle.net/2014/45031, 2011 SPIE Smart Structures and Materials, San Diego, California, March 6-10, 2011, JPL Open Repository
In last few years, the rate of development and advances in the field of EAP has accelerated significantly and it is increasingly getting closer to the point of finding them used in commercial products. Substantial development has been reported in the understanding of their drive... |
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
Bar-Cohen, Yoseph, 2010, "Refreshable Braille displays using EAP actuators", https://hdl.handle.net/2014/44786, 12th SPIE Conference - Electroactive Polymer Actuators and Devices(EAPAD), San Diego, California, March 7-11, 2010, JPL Open Repository
Refreshable Braille can help visually impaired persons benefit from the growing advances in computer technology. The development of such displays in a full screen form is a great challenge due to the need to pack many actuators in small area without interferences. In recent years... |
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 7, 2010
Sherrit, Stewart; Trebi-Ollennu, Ashitey; Bonitz, Robert; Bar-Cohen, Yoseph; Yen, Jesse T., 2010, "Compact sensitive piezoelectric mass balance for measurement of unconsolidated materials in space", https://hdl.handle.net/2014/44788, 12th SPIE Conference - Electroactive Polymer Actuators and Devices(EAPAD), San Diego, California, March 7-11, 2010, JPL Open Repository
In many in-situ instruments information about the mass of the sample could aid in the interpretation of the data and portioning instruments might require an accurate sizing of the sample mass before dispensing the sample. In addition, on potential sample return missions a method... |
Aug 2, 2009
Bar-Cohen, Yoseph, 2009, "Humanlike robots – the upcoming revolution in robotics", https://hdl.handle.net/2014/44616, SPIE Nanoscience and Engineering Symposium, San Diego, California, August 2-3, 2009, JPL Open Repository
Humans have always sought to imitate the human appearance, functions and intelligence. Human-like robots, which for many years have been a science fiction, are increasingly becoming an engineering reality resulting from the many advances in biologically inspired technologies. The... |
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 8, 2009
Bar-Cohen, Yoseph, 2009, "Electroactive Polymer (EAP) actuators for future humanlike robots", https://hdl.handle.net/2014/44618, 2009 SPIE Conference on Smart Structures and Materials, San Diego, California, March 8-12, 2009, JPL Open Repository
Human-like robots are increasingly becoming an engineering reality thanks to recent technology advances. These robots, which are inspired greatly by science fiction, were originated from the desire to reproduce the human appearance,functions and intelligence and they may become o... |
