Publicação
Piezoresistive sensing systems for predictive maintenance of automobile bumpers
| Resumo: | Road safety remains a major global concern as the number of vehicles continues to rise. This increase leads to a higher risk of traffic accidents, often resulting in serious human, financial, and structural consequences. While automotive engineering has made significant progress in enhancing crashworthiness improving how vehicles absorb and dissipate impact energy one key challenge persists: detecting hidden internal damage after a collision. Such damage may not be visible externally but can weaken the vehicle’s structural integrity over time, posing safety risks. Addressing this issue requires the development of intelligent systems capable of monitoring structural health in real time. These systems are essential for enabling predictive maintenance and enhancing vehicle safety. In this context, the current study, part of the Be.Neutral project, focuses on designing and testing a novel bumper monitoring system using piezoresistive sensors made from laser-induced graphene (LIG) on polyimide (PI) substrates. These materials were selected for their flexibility, thermal stability, and environmental durability. The sensors detect mechanical strain by converting it into measurable changes in electrical resistance, enabling continuous monitoring of structural integrity. To assess sensor performance, mechanical tests were conducted using a universal testing machine. Two approaches were used for electrical characterization: a high precision potentiostat and a Wheatstone bridge circuit connected to an Arduino, supporting real-time, multi-channel data collection. The sensors achieved consistent quality, with an average sheet resistance of 4.54 ± 0.29 Ω/sq. They could detect strain as low as 0.01%, with optimal performance at 0.5% strain, showing a mean gauge factor of 4.11 ± 1.47. Environmental testing confirmed their robustness under different temperature and humidity conditions. These findings highlight the promise of LIG-based sensors for smart, lightweight, and scalable vehicle monitoring systems, contributing to safer and more sustainable transportation. |
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| Autores principais: | Alves, David Alexandre Figueiredo |
| Assunto: | Road Safety Piezoresistive Laser-induced graphene Polyimide Strain Wheatstone bridge Gauge factor. |
| Ano: | 2025 |
| País: | Portugal |
| Tipo de documento: | dissertação de mestrado |
| Tipo de acesso: | acesso embargado |
| Instituição associada: | Universidade Nova de Lisboa |
| Idioma: | inglês |
| Origem: | Repositório Institucional da UNL |
| Resumo: | Road safety remains a major global concern as the number of vehicles continues to rise. This increase leads to a higher risk of traffic accidents, often resulting in serious human, financial, and structural consequences. While automotive engineering has made significant progress in enhancing crashworthiness improving how vehicles absorb and dissipate impact energy one key challenge persists: detecting hidden internal damage after a collision. Such damage may not be visible externally but can weaken the vehicle’s structural integrity over time, posing safety risks. Addressing this issue requires the development of intelligent systems capable of monitoring structural health in real time. These systems are essential for enabling predictive maintenance and enhancing vehicle safety. In this context, the current study, part of the Be.Neutral project, focuses on designing and testing a novel bumper monitoring system using piezoresistive sensors made from laser-induced graphene (LIG) on polyimide (PI) substrates. These materials were selected for their flexibility, thermal stability, and environmental durability. The sensors detect mechanical strain by converting it into measurable changes in electrical resistance, enabling continuous monitoring of structural integrity. To assess sensor performance, mechanical tests were conducted using a universal testing machine. Two approaches were used for electrical characterization: a high precision potentiostat and a Wheatstone bridge circuit connected to an Arduino, supporting real-time, multi-channel data collection. The sensors achieved consistent quality, with an average sheet resistance of 4.54 ± 0.29 Ω/sq. They could detect strain as low as 0.01%, with optimal performance at 0.5% strain, showing a mean gauge factor of 4.11 ± 1.47. Environmental testing confirmed their robustness under different temperature and humidity conditions. These findings highlight the promise of LIG-based sensors for smart, lightweight, and scalable vehicle monitoring systems, contributing to safer and more sustainable transportation. |
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