A highly sensitive low-cost strain sensor was fabricated in this research study based on microdispensing direct write (MDDW) technique. MDDW is an additive manufacturing approach that involves direct deposition of functional material to the substrate. The devices were printed directly onto a polymeric substrate by optimizing the fabrication parameters. A composite of silver and carbon was used as active sensor material where both materials in the composite have opposite resistance temperature coefficients. The ratio of materials in the composite was selected so that the effect of temperature on the resistance of overall composite was canceled out. This resulted in achieving temperature compensation or inherent independence of the strain sensor resistance on temperature without requiring any additional sensors and components. The sensor was further encapsulated by electrospray deposition, which is also an additive manufacturing approach, to eliminate the effect of humidity as well. Electrical and morphological characterizations were performed to investigate the output response of the sensors and their physical and structural properties. An analog signal conditioning circuit was developed for seamless interfacing of the sensor with any electronic system. The sensor had an excellent gauge factor of 45 and a strain sensitivity of 45 Ω/μɛ that is higher than most of the conventional strain sensors. The sensor's response showed excellent temperature and humidity compensation reducing the relative effect of temperature on the resistance by ∼99.5% and humidity by ∼99.8%.

中文翻译：

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通过增材制造工艺制造不受温度和湿度影响的银纳米粒子碳复合材料应变传感器

本研究基于微点胶直写（MDDW）技术制造了一种高灵敏度低成本应变传感器。MDDW 是一种增材制造方法，涉及将功能材料直接沉积到基材上。通过优化制造参数，将器件直接打印到聚合物基板上。银和碳的复合材料被用作有源传感器材料，其中复合材料中的两种材料具有相反的电阻温度系数。选择复合材料中的材料比例，以抵消温度对整个复合材料电阻的影响。这导致实现温度补偿或应变传感器电阻对温度的固有独立性，而不需要任何额外的传感器和组件。该传感器通过电喷雾沉积进一步封装，这也是一种增材制造方法，以消除湿度的影响。进行电气和形态表征以研究传感器的输出响应及其物理和结构特性。开发了模拟信号调理电路，用于传感器与任何电子系统的无缝连接。该传感器具有 45 的出色应变系数和 45 Ω/μɛ 的应变灵敏度，高于大多数传统应变传感器。传感器的响应表现出出色的温度和湿度补偿，将温度对电阻的相对影响降低约 99.5%，湿度对电阻的相对影响降低约 99.8%。