| Title: |
Development, Classification and Biomedical Applications of Nano Composite Piezoresponsive Foam |
| Authors: |
Merrell, Aaron Jake |
| Source: |
Theses and Dissertations |
| Publisher Information: |
BYU ScholarsArchive |
| Publication Year: |
2018 |
| Collection: |
Brigham Young University (BYU): ScholarsArchive |
| Subject Terms: |
triboelectric; special detection; piezoresponsive; self-sensing foam; football helmet; impact detection; impact energy; impact velocity; acceleration; energy absorption; Engineering; Mechanical Engineering |
| Description: |
This dissertation focuses on the development of and applications for Nano-Composite Piezoresponsive Foam (NCPF). This self-sensing foam sensor technology was discovered through research in a sister technology, High Deflection Strain Gauges (HDSG), and was subsequently developed with some of the same base materials. Both technologies use nano and micro conductive additives to provide electrically responsive properties to materials which otherwise are insulative. NCPF sensors differ from HDSGs in that they provide a dual electrical response to dynamic and static loading, which is measured through an internally generated charge, or a change in resistance. This dissertation focuses on the development of the dynamic or piezoresponsive aspect of the NCPF sensors which tends to have more consistent electrical response over a larger number of cycles. The primary development goal was to produce a sensor that was accurate, while providing a consistent, repeatable response over multiple impacts. The hypothesized electric generation is attributed to a triboelectric interaction between the conductive additives and the polyurethane foam matrix. This hypothesis was validated by examining different conductive additives with varying loading levels and specific surface areas while accounting for other design considerations such as the electrode used to harvest the response. The results of this analysis support the triboelectric model and point to carbon or nickel-based additives for optimal performance. The NCPF response measured by digital signal acquisition devices is directly dependent upon its input impedance. Increased input capacitance has a negative effect on the signal, however, higher input resistance has a positive linear correlation to voltage. Other considerations that affect the electrical response include the temperature and humidity in which the sensor is used and result in a scaled electrical response.NCPF sensors are ideally suited for use in systems which benefit from impact energy attenuation while measuring ... |
| Document Type: |
text |
| File Description: |
application/pdf |
| Language: |
unknown |
| Relation: |
https://scholarsarchive.byu.edu/etd/7338; https://scholarsarchive.byu.edu/context/etd/article/8338/viewcontent/etd9898.pdf |
| Availability: |
https://scholarsarchive.byu.edu/etd/7338; https://scholarsarchive.byu.edu/context/etd/article/8338/viewcontent/etd9898.pdf |
| Accession Number: |
edsbas.EAF6B290 |
| Database: |
BASE |