Development of pressure sensors for smart textiles (original) (raw)

A Comparative Characterization of Smart Textile Pressure Sensors

2019 41st Annual International Conference of the IEEE Engineering in Medicine and Biology Society (EMBC), 2019

This research study investigates the impact of various insulating textile materials on the performance of smart textile pressure sensors made of conductive threads and piezo resistive material. We designed four sets of identical textile-based pressure sensors – each of them integrating a different insulating textile substrate material. Each of these sensors underwent a series of tests that linearly increased and decreased a uniform pressure perpendicular to the surface of the sensors. The controlled change of the integration layer altered the characteristics of the pressure sensors including both the sensitivity and pressure ranges. Our experiments highlighted that the manufacturing design technique of textile material has a significant impact on the sensor; with evidence of reproducibility values directly relating to fabric dimensional stability and elasticity.

Flexible piezoresistive pressure sensors for smart textiles

IOP Conference Series: Materials Science and Engineering, 2018

This paper presents the development of polymer integration in e polyethylene film with commer connection, as shown in Figure 1. The electrode elements should also be flexible. In this work, plated conductive fab variation of electrical resistance when subjected to pressure when pressure increases Flexible 1. Introduction This paper presents the development of polymer integration in e polyethylene film with commer The sensor construction comprises the transducing element as well as two electrodes for electrical connection, as shown in Figure 1. The electrode elements should also be flexible. In this work, plated conductive fab variation of electrical resistance when subjected to pressure when pressure increases Flexible ntroduction This paper presents the development of polymer integration in e polyethylene film with commer The sensor construction comprises the transducing element as well as two electrodes for electrical connection, as shown in Figure 1. The electrode elements should also be flexible. In this work, plated conductive fab variation of electrical resistance when subjected to pressure when pressure increases Flexible ntroduction This paper presents the development of polymer integration in e polyethylene film with commer The sensor construction comprises the transducing element as well as two electrodes for electrical connection, as shown in Figure 1. The electrode elements should also be flexible. In this work, plated conductive fab variation of electrical resistance when subjected to pressure when pressure increases Flexible p ntroduction This paper presents the development of polymer integration in e polyethylene film with commer The sensor construction comprises the transducing element as well as two electrodes for electrical connection, as shown in Figure 1. The electrode elements should also be flexible. In this work, plated conductive fab variation of electrical resistance when subjected to pressure when pressure increases piezoresistive

Impact of Fabric Properties on Textile Pressure Sensors Performance

Sensors

In recent years, wearable technologies have attracted great attention in physical and chemical sensing applications. Wearable pressure sensors with high sensitivity in low pressure range (<10 kPa) allow touch detection for human-computer interaction and the development of artificial hands for handling objects. Conversely, pressure sensors that perform in a high pressure range (up to 100 kPa), can be used to monitor the foot pressure distribution, the hand stress during movements of heavy weights or to evaluate the cyclist’s pressure pattern on a bicycle saddle. Recently, we developed a fully textile pressure sensor based on a conductive polymer, with simple fabrication and scalable features. In this paper, we intend to provide an extensive description on how the mechanical properties of several fabrics and different piezoresistive ink formulation may have an impact in the sensor’s response during a dynamic operation mode. These results highlight the complexity of the system due t...

Conductive Fiber-Based Ultrasensitive Textile Pressure Sensor for Wearable Electronics

Advanced materials (Deerfield Beach, Fla.), 2015

A flexible and sensitive textile-based pressure sensor is developed using highly conductive fibers coated with dielectric rubber materials. The pressure sensor exhibits superior sensitivity, very fast response time, and high stability compared with previous textile-based pressure sensors. By using a weaving method, the pressure sensor can be applied to make smart gloves and clothes which can control machines wirelessly as human-machine interfaces.

Design, fabrication and metrological evaluation of wearable pressure sensors

Pressure sensors are valuable transducers that are necessary in a huge number of medical application. However, the state of the art of compact and lightweight pressure sensors with the capability of measuring the contact pressure between two surfaces (contact pressure sensors) is very poor. In this work, several types of wearable contact pressure sensors are fabricated using different conductive textile materials and piezo-resistive films. The fabricated sensors differ in size, the textile conductor used and/or the number of layers of the sandwiched piezo-resistive film. The intention is to study, through the obtaining of their calibration curves, their metrological properties (repeatability, sensitivity and range) and determine which physical characteristics improve their ability for measuring contact pressures. It has been found that it is possible to obtain wearable contact pressure sensors through the proposed fabrication process with satisfactory repeatability, range and sensitivity; and that some of these properties can be improved by the physical characteristics of the sensors.

Comparative analysis of knitted pressure sensors

2018

Textile sensors have a wide range of applications in wearable monitoring systems due to their lightweight, elastic and flexible properties. The present paper is devoted to the comparative analysis of effects of pressure load on knitted pressure sensors of different shapes and their durability to washing. All the developed sensors are knitted using cotton yarns and copper coated acrylic yarns on a circular knitting machine. The sensor performance properties and durability have been tested experimentally. Each type of sensors was tested under quasi-static and dynamic loadings with various pressure forces. Relations between the applied pressure force and sensor sensitivity and responses were analysed. It was found that filled shape sensors are more sensitive to low pressures. Testing of the sensors under dynamic loads confirmed high repeatability of measurements and sensitivity even to small variations of the loading level. One of the most common problems of textile-based sensors that essentially restrict application of smart textiles is their care. Therefore, durability of the designed sensors to washing was been studied, as well. It was found that knit density affects sensor durability to washing. Sensors with a higher knit density showmore stable and uniform electrical resistance increase, whereas sensors with a lower knit density show unstable durability and higher variation in electrical resistance changes. Also, configuration of the sensors affects the electrical resistance changes due to washing.

Wearable pressure sensor based on solution-coated fabric for pulse detection

2022 IEEE International Conference on Flexible and Printable Sensors and Systems (FLEPS)

Wearable devices have developed significantly due to the use and development of various materials such as organic materials and carbon nanotubes, and the demand for wearables is also growing. The piezoresistive pressure sensor has been developed using conductive fabric coated with a simple solution coating process. The fabric has an open structure with the interconnected top and lower layers that can be utilized as pressure sensors and can detect physical movements. The piezoresistive pressure sensor has excellent resistance linearity in the low pressure to 10kPa range, as well as consistent resistance to strain up to 20% when stretched. The pressure sensor array can detect pressure-induced local deformation and will be expected to contribute considerably to the development of wearable devices with a simplified process.

Easy-to-Build Textile Pressure Sensor

Sensors (Basel, Switzerland), 2018

This article presents the design, construction, and evaluation of an easy-to-build textile pressure resistive sensor created from low-cost conventional anti-static sheets and conductive woven fabrics. The sensor can be built quickly using standard household tools, and its thinness makes it especially suitable for wearable applications. Five sensors constructed under such conditions were evaluated, presenting a stable and linear characteristic in the range 1 to 70 kPa. The linear response was modeled and fitted for each sensor individually for comparison purposes, confirming a low variability due to the simple manufacturing process. Besides, the recovery times of the sensors were measured for pressures in the linear range, observing, for example, an average time of 1 s between the moment in which a pressure of 8 kPa was no longer applied, and the resistance variation at the 90% of its nominal value. Finally, we evaluated the proposed sensor design on a classroom application consistin...

Performances evaluation of piezoresistive fabric sensors as function of yarn structure

2013 35th Annual International Conference of the IEEE Engineering in Medicine and Biology Society (EMBC), 2013

Abstract² This work focus on the characterization of piezoresistive fabric sensors, realized with conductive yarns that are similar in term of conductive components, but different only in term of geometry, the yarns have been realized according two different production processes while the sensors have been produced following the same process, fabric structure and same materials. The different geometry of the yarns affects dramatically conductivity and functionality of the sensors in term of sensitivity and hysteresis minimization. This result confirms that the functional components can be engineered during the different phases of the process production; to get new properties and new applications. Small changes at fibers level can be fundamental to improve the properties of the fabric sensors.

Design and Fabrication of a Capacitance Based Wearable Pressure Sensor Using E-textiles

This paper addresses the methods used for the design and fabrication of a capacitance based wearable pressure sensor fabricated using neoprene and (SAC) plated Nylon Fabric. The experimental set up for the pressure sensor is comprised of a shielded grid of sensing modules, a 555 timer based transduction circuitry, and an Arduino board measuring the frequency of signal to a corresponding pressure. The fundamental design parameters addressed during the development of the pressure sensor presented in this paper are based on size, simplicity, cost, adaptability, and scalability. The design approach adopted in this paper results in a sensor module that is less obtrusive, has a thinner and flexible profile, and its sensitivity is easily scalable for 'smart' product applications across industries associated to sports performance, ergonomics, rehabilitation, etc.