Engineering topics
Publications and source records attributed to Lih, S. S..
This paper presents a set of candidate components: MEMS based large stroke (>100 microns) ultra lightweight (~0.01 gm) discrete inch worm actuator technology, and a distributed actuator technology, in the context of a novel lightweight active flexure-hinged substrate concept that uses the nanolaminate face sheet.
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This paper will discuss the development of thin-shell, nano-laminate mirror substrates that are capable of being electro-actively figured. This technology has the potential to substantially reduce the cost of space based optics by allowing replication of ultra-lightweight primary mirrors from a master precision tool.
The Ionomeric Polymer-Metal Composites (IPMC) as a type of electroactive polymers are attractive actuation materials because of their features of large electrically induced bending, mechanical flexibility, low excitation voltage, low density, and ease of fabrication.
IPMC is an electroactive polymer (EAP) that has been the subject of research and development since 1992. Its required low activation voltage and the large bending strain led to its consideration for various potential applications. However, before the benefits of IPMC can be effectively exploited for practical use, the electromechanical behavior of this group of EAP materials must be properly understood and quantified.
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This paper evaluates the precision control of struts of the micro-space shell structure.
This paper reports a study of precision actuation and control for micro-shell laminated space structures made of smart materials.
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The Leaky Lamb wave (LLW) technique is approaching a maturity level that is making it an attractive quantitative NDE tool for composites and bonded joints.
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The use of obliquely insonified ultrasonic waves has shown great promise in providing information about flaw characteristics and material properties of composite materials.
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The leaky Lamb waves (LLW) technique is approaching a maturity level that is making it attractive quantitative NDE tool for composites and bonded joints.
In recent years, a great deal of research has been exerted to developing NDE methods for the characterization of the material properties of composites as well as other space structural materials. The need for information about such parameters as the elastic properties, density, and thickness are critical to the safe design and operation of such structural materials. Ultrasonics using immersion methods has played an important role in these efforts due to its capability, cost effectiveness, and ease of use. The authors designed a series of ultrasonic oblique insonification experiments in order to develop a practical field applicable NDE method for space structures.