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Silicon piezoresistive pressure sensor dies are mounted on a ceramic substrate where the signal conditioning electronics are implemented in thick film technology. In this paper some of these techniques, e.g. special attachment and bonding requirements, methods for temperature compensation, the principles of parameter adjustment, and encapsulation, are presented. For illustration two examples are described. The first is a multipoint monitoring system with 720 measuring points in a test mattress. The second example is a family of industrial pressure transducers.

Carbon nanotube (CNT) thread ' s piezoresisitive strain sensing properties of gauge factor, linearity, hysteresis, consistency, temperature stability, and bandwidth were evaluated. This evaluation was motivated by little information in literature combined with the need to understand these properties for commercial use. The paper aims to discuss these issues.

The study here analyzes as-spun CNT thread built into unidirectional glass fiber composites and mounted onto aluminium beams with epoxy to evaluate strain sensing properties. The analyses utilize known sensor parameter definitions to quantify sensor performance.

CNT thread can provide reliable and robust strain measurements for composite and metallic structures. The strain sensor performance meets or exceeds other strain sensors in performance.

CNT thread ' s piezoresistive effect is not well understood in terms of Poisson ' s ratio and nanotube contact. More research needs to be carried out to better understand this relationship and optimize the sensor thread.

CNT thread can be utilized as a robust strain sensor for composite and metallic structures. It can also be built into composite materials for embedded strain and damage monitoring. By monitoring composite materials with the sensor thread, reliability will significantly increase. In turn, this will lower safety factors and revolutionize inspection methods for composite materials.

This paper is the first to comprehensively evaluate key strain sensing properties of CNT thread. With all this strain sensor information in one spot, this should help expedite the use of this technology in other research and industry.

This paper describes the stages in the construction of sensors implemented in thick film technology. The use of CAD facilities greatly reduces the time required for development, and automatic design rule checking minimises errors. Steps in the fabrication from layout to finished mask(s) are detailed and specific examples given. Strain gauges using piezoresistive properties of thick film resistor inks with various sheet resistivities (Du Pont HS80 series) printed on insulated stainless steel substrates were examined under strains ranging from 0 to ±1000 microstrain. Results show gauge factors to be dependent on the ink's sheet resistivity and range from 2 to 12. The temperature coefficients of resistance were determined over temperatures of +20°C to +140°C, revealing good tracking and reproducibility.

Inspired by the development of eco-friendly flexible electronics, this paper aims to present a series of paper-based electronics drawn by pencils, which can be used as favorable sensing elements in daily life.

Pencil traces are deposited on the porous surface of Xerox paper by the mechanical exfoliation during writing process, which can be used as basic components to construct functional electronics for daily sensing applications. By changing pencil grade, the obtained traces can work as conductive wires, electrodes, resistors and piezoresistive gauges.

The experimental results confirm their practical applications in sensing several daily activities, including finger motion, touching and the temperature of water in paper cup. Moreover, the used electronics can be easily handled and recycled.

The shortage in functionality, reliability and performance consistency induced by manual operation is an evident challenge, which makes the pencil-on-paper devices more suitable to work as a temporary solution to satisfying the demands from emergency circumstances.

The pencil-on-paper devices, motivated by the electroconductibility and piezoresistivity of pencil trace, can be explored as sensing prototypes in detecting daily activities. Meantime, their advances in easy accessibility, rapid fabrication, low cost and eco-fitness endow them excellent capacity of meeting the “on-site, real-time” demands.

The purpose of this study is to find a new design that can increase the sensitivity of the sensor without sacrificing the linearity. A novel and very efficient method for increasing the sensitivity of MEMS pressure sensor has been proposed for the first time. Rather than perforation, we propose patterned thinning of the diaphragm so that specific regions on it are thinner. This method allows the diaphragm to deflect more in response with regard to the pressure. The best excavation depth has been calculated and a pressure sensor with an optimal pattern for thinned regions has been designed. Compared to the perforated diaphragm with the same pattern, larger output voltage is achieved for the proposed sensor. Unlike the perforations that have to be near the edges of the diaphragm, it is possible for the thin regions to be placed around the center of the diaphragm. This significantly increases the sensitivity of the sensor. In our designation, we have reached a 60 per cent thinning (of the diaphragm area) while perforations larger than 40 per cent degrade the operation of the sensor. The proposed method is applicable to other MEMS sensors and actuators and improves their ultimate performance.

Instead of perforating the diaphragm, we propose a patterned thinning scheme which improves the sensor performance.

By using thinned regions on the diaphragm rather than perforations, the sensitivity of the sensor was improved. The simulation results show that the proposed design provides larger membrane deflections and higher output voltages compared to the pressure sensors with a normal or perforated diaphragm.

The proposed MEMS piezoelectric pressure sensor for the first time takes advantage of thinned diaphragm with optimum pattern of thinned regions, larger outputs and larger sensitivity compared with the simple or perforated diaphragm pressure sensors.

To provide corporate and technical details of the US‐based Endevco Corporation. This company is a leading manufacturer of sensors and systems for measuring vibration, shock and other physical variables.Design/methodology/approach – This profile considers the Endevco company structure, technology, products, markets and applications, including historical achievements and recent developments.Findings – This paper discusses the company's use of piezoelectric ceramic and microengineered silicon technologies in a range of high performance sensors for measuring shock, acceleration, vibration and pressure.Originality/value – This provides an insight into the Endevco company structure, products, technologies and markets.

This paper aims to present the fabrication and testing of a pressure sensor integrated with Hall effect sensors and permanent magnets arranged in two configurations to measure pressure in the range of 0–1 bar. The sensor is fabricated using stainless steel (SS) and can be used in high-temperature and highly corrosive environments. The fabricated sensor is of low cost, self-packaged and the differential arrangement helps in compensating for any ambient temperature variations.

The sensor deflects of a circular diaphragm with a simple rigid mechanical structure to convert the applied pressure to a Hall voltage output. Two sensor designs are proposed with a single pair of Hall sensors and magnets and a differential configuration with two Hall sensors and magnets. Two sensor designs are designed, fabricated and tested for their input–output characteristics and the results are compared.

The fabricated sensors are calibrated for 25 cycles of ascending and descending pressure in steps of 0.1 bar. Various static characteristics like nonlinearity, hysteresis and % error are estimated for both the sensor designs and compared with the existing Hall effect based pressure sensors. The differential arrangement design was found to have better characteristics as compared to the other design from the experimental data.

This paper focuses on fabricating and testing a novel differential Hall effect based pressure sensor. The differential arrangement of the sensor aids in the compensation of ambient temperature variations and the use of SS enables the sensor in high-temperature and highly corrosive applications. The proposed sensor is low cost, simple and self-packaged, and found to have high repeatability and good linearity compared to other similar Hall effect based pressure sensors available in the literature.

This paper presents results of work aimed at characterising the zero offset stability in novel thick film strain gauges. The devices studied are z‐axis (k₃₃) load sensors fabricated on insulated stainless steel substrates and include examples of novel commercially developed force sensors. Devices loaded with compressive strains using a purpose designed test jig were found to exhibit a significant zero offset shift, which is negative up to a certain level (typically 1,000 micro strains) and then increasingly positive when strained beyond this point. Repeated cycles of loading then produced a certain level of stability until the previous maximum value of applied strain was exceeded. Temperature coefficient of resistance (TCR) measurements showed the devices to exhibit characteristics that depend significantly on the device geometry. The TCR was found to increase positively with increasing device thickness and surface area. The effect of overglazing the devices was found to decrease the TCR.

Advanced devices and fabrication methods dominated the second Eurosensors conference held in The Netherlands in November 1988. Rory Chase reports.

Reviews the benefits and potential application of tactile sensors for use with robots.

Includes the most recent advances in both the design/manufacturing of various tactile sensors and their applications in different industries. Although these types of sensors have been adopted in a considerable number of areas, the applications such as, medical, agricultural/livestock and food, grippers/manipulators design, prosthetic, and environmental studies have gained more popularity and are presented in this paper.

Robots can perform very useful and repetitive tasks in controlled environments. However, when the robots are required to handle the unstructured and changing environments, there is a need for more elaborate means to improve their performance. In this scenario, tactile sensors can play a major role. In the unstructured environments, the robots must be able to grasp objects (or tissues, in the case of medical robots) and move objects from one location to another.

In this work, the emphasis was on the most interesting and fast developing areas of the tactile sensors applications, including, medical, agriculture and food, grippers and manipulators design, prosthetic, and environmental studies.