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Owing to the technology growth, especially in Microsystems technology and Nanotechnology, new products will provide new ways to sense variables that are crucial for product improvement and system reliability. A big concern of the scientific community is the measurement of low level flow measurements, especially for the biomedical and/or systems on a chip approaches.Design/methodology/approach – A new flow meter concept design consists of a surface micromachined sensor having an optical high reflective mirror made of gold, which is attached to unique cantilever designs that bend due to the drag force of mass flow. The bending of the cantilevers produces the mirror to approach/depart from an optical fiber end‐tip. The reflective light to fiber is modulated using a Fabry‐Perot interferometry technique to determine the mirror separation to the fiber, which corresponds to the mass flow.Findings – The new concept design shows a big potential approach to measure low flow measurements for air, gas and liquids of low viscosity. The results of this concept, through finite element analysis, show that the material used to build the sensor, makes them excellent candidates for fabrication. The stresses of the materials and allowable (readable) bending are among the tolerances of such materials/construction‐design. The sensor is not affected by electromagnetic interference and does not require electrical currents to sense, i.e. it is perfectly suited for biomedical and low mass‐flow sensing such as lab‐on‐chip applications.Originality/value – Among all approaches to sense low flow measurements, most of them need either “big” turbine approaches (dimensions over 1 cm diameter), or the need of an electrical approach needed in the end measurement sensor. This work proposes a non‐electrical approach.

With the increasing development of the surgical robots, the opto-mechatronic technologies are more potential in the robotics system optimization. The optic signal plays an important role in opto-mechatronic systems. This paper aims to present a review of the research status on fiber-optic-based force and shape sensors in surgical robots.

Advances of fiber-optic-based force and shape sensing techniques in the past 20 years are investigated and summarized according to different surgical requirement and technical characteristics. The research status analysis and development prospects are discussed.

Compared with traditional electrical signal conduction, the phototransduction provides higher speed transmission, lower signal loss and the immunity to electromagnetic interference in robot perception. Most importantly, more and more advanced optic-based sensing technologies are applied to medical robots in the past two decades because the prominence is magnetic resonance imaging compatibility. For medical robots especially, fiber-optic sensing technologies can improve working security, manipulating accuracy and provide force and shape feedback to surgeon.

This is a new perspective. This paper mainly researches the application of optical fiber sensor according to different surgeries which is beneficial to learn the great potential of optical fiber sensor in surgical robots. By enumerating the research progress of medical robots in optimization design, multimode sensing and advanced materials, the development tendency of fiber-optic-based force and shape sensing technologies in surgical robots is prospected.

The use of fibre optic sensors is a relatively new development but the future applications are enormous

To examine the range of fibre‐optic sensors available for monitoring the integrity of buildings and civil engineering structures.

Explains the need for structural monitoring and reviews the types of fibre‐optic sensors. Concentrating on elongation and temperature sensing, shows how each technology works, which companies supply the products, and gives an overview of their technical specifications.

Fibre optics are able to provide integrated, single‐point and distributed sensor systems. The fibre is a communication channel as well as a sensor, and in some systems, carries highly multiplexed data over considerable distances to a central monitoring station. The take‐up of this technology in structural sensing is helped by appropriate packaging that assists attachment to buildings. Durability and measurement stability give a continuity of measurement that was not previously possible.

An introduction to the range of sensors applicable to structural monitoring, of general interest to scientists, but particularly to civil and constructional engineers.

This paper aims to provide details of the major optical gas sensing techniques and their applications.

Following an introduction, this paper first identifies the major gas sensing technologies and provides an overview of optical sensing techniques. The sources and impact of the gases most frequently sensed by optical methods are listed. Three non-absorption-based and nine absorption-based methods and their main applications are then described in detail. Brief concluding comments are drawn.

All manner of optical gas sensing techniques have been commercialised and while the majority are absorption-based, several other methods also play a significant role. Some optical gas sensors offer advanced capabilities such as remote monitoring, the creation of 2D and 3D distribution maps, detection of parts per trillion levels and even the visualisation of gases in real time. They play a vital role in protecting workers from hazardous gases, controlling and minimising air pollution and monitoring the atmospheric environment, as well as being used in the food, medical, process, power generation and other industries.

This paper provides a detailed insight into optical gas sensing techniques and their uses.

The rapid advances in recent years made within the field of fibre optics and opto‐electronics open up new opportunities within many areas.

The purpose of this paper is to consider a detailed investigation of transversal magnetic (TM) nonlinear magnetooptical integrated optical sensor. The sensitivities of two sensors are presented. The first sensor composed of a dielectric thin film surrounded by a lossless, nonmagnetic, isotropic cladding exhibiting a local Kerr‐like dielectric nonlinearity, and a magnetic substrate chosen to be an iron garnet. The second sensor is formed by exchanging the cladding and the substrate media of the first sensor. The homogenous sensitivities of both sensors are calculated as a function of the waveguide thickness and the effective refractive index. The effect of nonlinearity on the sensitivities for both sensors is investigated.

The homogenous sensitivities of both sensors are calculated as a function of the waveguide thickness and the effective refractive index. The effect of nonlinearity on the sensitivities for both sensors is investigated. Numerical calculations are performed using the Maple program.

It was found that the sensitivity for the first sensor sensitivity increases with nonlinearity. While the sensitivity for the second sensor is hardly affected by the change of nonlinearity. It was also found that the thickness of the guiding layer is a critical parameter for the sensitivity of the optical sensor with the optimum thickness being just above cut‐off in case of the first structure and at the cut‐off in the case of the second structure.

A detailed investigation of TM nonlinear magnetooptical integrated optical sensor is considered. The two proposed structures are used to investigate the parameters to get the optimal sensitivity, which is an important issue is the sensor design.

The aim of this paper is to create a sensor that can measure the contact status with high‐resolution than ever.

This paper proposes a new type of optical tactile sensor that can detect surface deformation with high precision by using the principle of optical lever. A tactile sensor is constructed that utilizes the resolution of a camera to the maximum by using transparent silicone rubber as a deformable mirror surface and taking advantage of the reflection image.

It has been found that the sensor can sense the deformation by the object with 1 percent error rate in simulation. In implementation of this time, the error rate results 10 percent.

This sensor can be used with broad applications by combining with other devices. As one of future work, the zero method will be used by using active patterns and get more accurate information.

Using the transparent silicone rubbers the sensor enables very simple and low cost and high‐resolution detection method. In addition, the simplicity of our sensor results various applications. For example, the transparency makes the sensor a light pathway, so the sensor can be a contactless sensor or an interactive device.

The concept of a tactile sensing method is introduced which can utilize the resolution of a camera to the maximum possible extent and can detect surface deformation by using the principle of optical lever.

This study aims to optimize the structure of gold-sputtered U-shaped plastic fiber sensors.

A group of U-shaped Au-sputtered plastic optical fiber sensing probes with polishing angles of 45°, 90° and 135° is prepared.

The experimental results show that the spectral response and sensitivity of the sensor at 45°polishing angle is twice that of the sensor at 90°.

Due to the limitations of laboratory temperature and equipment, the overall effect has not reached the ideal, but the expected effect has been obvious. Experiments also optimize the sensor.

Optical fiber sensing has always been an indispensable part of various fields.

Sensor optimization is of great help to the progress of technology and the development of science and technology.

The authors have no conflicts of interest to disclose.

Seepage of the dam is an important safety problem, which may cause internal erosion of the structure. In the field of seepage monitoring in civil engineering, the distributed optical fiber sensing technology based on the temperature tracing method has been paid more attention due to its unique advantages of high sensitivity, good stability and high resolution. The purpose of this paper is to make a review of the existing related research, so as to facilitate the later scholars to understand and further study more systematically.

In this paper, three kinds of commonly used distributed fiber temperature measurement technologies are introduced. Based on the working principle, monitoring system, theoretical analysis, experimental research and engineering application of the fiber seepage monitoring technology, the present situation of dam seepage monitoring based on distributed fiber is reviewed in detail and their advantages and disadvantages are compared.

The thermal monitoring technology of seepage measurement depends on the accuracy of optical fiber temperature measurement (including the accuracy of the system and the rationality of the discrimination method), the correct installation of optical fiber and the quantitative analysis of temperature data. The accuracy of the current monitoring system can basically meet the existing measurement requirements, but the correct installation of optical fiber and the calibration of temperature data need to be further studied for different discrimination methods, and this field has great research value.

At present, there are many applications and research studies of optical fiber sensing in the field of structural health monitoring, and there are also reviews of related aspects. However, there is little or no review only in the field of seepage monitoring. This paper summarizes the research and application of optical fiber sensing in the field of seepage monitoring. The possibility of the gradient method to find its new prospect with the development of monitoring systems and the improvement of temperature resolution is discussed. The idea of extending the seepage monitoring method based on distributed optical fiber thermal monitoring technology to other monitoring fields is also given in the paper.