Touch Mode Research Articles

Optimal design parameter estimation and analytical investigation of MEMS quadruple touch mode capacitive pressure sensor

Purpose Touch mode capacitive pressure sensors (TMCPS) offer superior sensitivity and linearity in comparison to normal mode CPS and have therefore seen substantial improvements in modeling and construction. This study aims to develop a sensor that is highly robust, with near-linear output characteristics, increased sensitivity and superior overload protection, making it an ideal choice for deployment in harsh industrial environments. Design/methodology/approach The proposed sensor design uses a substrate with a multi-step notch, introducing a new quadruple TMCPS and uses a small deflection model for mathematical analysis. Addition of a multi-step notch to traditional touch mode capacitive sensors results in quadruple touch regions which further enhances its operational range performance. Findings The simulation of diaphragm deflection in response to pressure is carried out by using COMSOL Multiphysics, whereas MATLAB is used for analytical simulations pertaining to variations in capacitance and capacitive sensitivity. Comparing with earlier models, there is a noticeable enhancement in capacitance, experiencing a fivefold increase. The achieved value stands at 50.1 pF, reflecting improved sensitivity for applied pressure ranging from 0 to 2 MPa. Originality/value In existing literature to improve the performance of the single TMCPS, a double-sided TMCPS has been developed. To enhance sensor performance, a substrate with a multi-step notch is proposed. The notch creates four touch regions with varying gap depths, resulting in increased capacitance and capacitive sensitivity.

MEMS capacitive pressure sensor: analysis, theoretical modeling, simulation and performance comparison of the effect of a conical notch

Abstract Micro-Electro-Mechanical Systems (MEMS) pressure sensors are widely used in various applications due to their high sensitivity, low power consumption, and compactness. This work involves the design and simulation of a MEMS-based Touch Mode Capacitive Pressure Sensor (TMCPS). The proposed sensor is based on a substrate with an integrated conical notch featuring a circular diaphragm, aiming to enhance the key performance parameters of the sensor. The integration of a conical notch in the substrate increases the touch area between the diaphragm and substrate compared to the literature, ensuring increased capacitance and capacitive sensitivity. In this work the mathematical analysis of deflection of a circular diaphragm employing thin plate theory, capacitance, and capacitive sensitivity, along with step-by-step explanations, is provided. The results are obtained from MATLAB simulations. The deflection of the diaphragm is validated through Finite Element Analysis (FEA) using COMSOL Multiphysics. The proposed work demonstrates a significant improvement in sensor sensitivity compared to the existing literature.

A Circular Touch Mode Capacitive Rainfall Sensor: Analytical Solution and Numerical Design and Calibration

A circular capacitive rainfall sensor can operate from non-touch mode to touch mode; that is, under the action of enough rainwater, its movable electrode plate can form a circular contact area with its fixed electrode plate. Therefore, the weight of rainwater is borne by only its movable electrode plate in non-touch mode operation but by both its movable and fixed electrode plates in touch mode operation, and the total capacitance of its touch mode operation is much larger than that of its non-touch mode operation. Essential to its numerical design and calibration is the ability to predict the deflection shape of its moveable electrode plate to determine its total capacitance. This requires the analytical solution to the fluid–structure interaction problem of its movable electrode plate under rainwater. In our previous work, only the analytical solution for the fluid–structure interaction problem before its movable electrode plate touches its fixed electrode plate was obtained, and how to numerically design and calibrate a circular non-touch mode capacitive rainfall sensor was illustrated. In this paper, the analytical solution for the fluid–structure interaction problem after its movable electrode plate touches its fixed electrode plate is obtained, and how to numerically design and calibrate a circular touch mode capacitive rainfall sensor is illustrated for the first time. The numerical results show that the total capacitance and rainwater volume when the circular capacitive rainfall sensor operates in touch mode is indeed much larger than that when the same circular capacitive rainfall sensor operates in non-touch mode, and that the average increase in the maximum membrane stress per unit rainwater volume when the circular capacitive rainfall sensor operates in touch mode can be about 20 times smaller than that when the same circular capacitive rainfall sensor operates in non-touch mode. This is where the circular touch mode capacitive rainfall sensor excels.

Human-animal entanglements in bushmeat trading in Sierra Leone: An ethnographic assessment of a potential zoonotic interface.

'Bushmeat' markets are often portrayed as chaotic spaces where exotic wild animals are sold. They are hypothesized to be important sites for zoonotic disease transmission, given the prolonged and intense nature of the cross-species encounters that occur within them. Whilst such markets have received some attention from researchers, rich qualitative descriptions of everyday practices in these markets are rare. Depictions of wild animal markets as sites for potential viral amplification often rely on exoticizing assumptions and narratives rather than actual evidence, and in some cases are based more on ideology than on science. We provide an in-depth ethnographic account of two bushmeat markets in Bo, Sierra Leone. Our analysis goes beyond common assumptions that zoonotic risk is located solely in the knowledge and behaviours of traders. Our account sheds light on the modes of touch, closeness and contact that shape this hypothesised zoonotic interface, outlining the possible risks to different people who use and spend time in the market. We found that inadequate infrastructure and sanitation facilities created risks of zoonotic disease transmission for diverse actors including traders, customers, children, and the wider public. Butchering and trading practices frequently resulted in people directly and indirectly encountering animal fluids. We also discuss how public health management of these markets focused on individual behaviours rather than on improving conditions. Urgent sanitary reform and infrastructure upgrades in these sites that support the economic needs of traders could encourage voluntary compliance with biosafety measures amongst traders seeking to balance responsibilities to family and public health. Our study reveals the value of moving beyond exoticized narratives about bushmeat markets to yield situated insights for reducing risk at this interface.

An Improved Theory for Designing and Numerically Calibrating Circular Touch Mode Capacitive Pressure Sensors

The design, especially the numerical calibration, of a circular touch mode capacitive pressure sensor is highly dependent on the accuracy of the analytical solution of the contact problem between the circular conductive membrane and the rigid plate of the sensor. In this paper, the plate/membrane contact problem is reformulated using a more accurate in-plane equilibrium equation, and a new and more accurate analytical solution is presented. On this basis, the design and numerical calibration theory for circular touch mode capacitive pressure sensors has been greatly improved and perfected. The analytical relationships of pressure and capacitance are numerically calculated using the new and previous analytical solutions, and the gradually increasing difference between the two numerical calculation results with the gradual increase in the applied pressure is graphically shown. How to use analytical solutions and analytical relationships to design and numerically calibrate a circular touch mode capacitive pressure sensor with a specified pressure detecting range is illustrated in detail. The effect of changing design parameters on capacitance–pressure analytical relationships is comprehensively investigated; thus, the direction of changing design parameters to meet the required or desired range of pressure or capacitance is clarified.

Touch-text answer for human-robot interaction via supervised adversarial learning

In daily life, touch modality plays an important role in conveying human intentions and emotions. To further improve touch-based human-robot interaction, robots need to infer human emotions from touch signals and respond accordingly. Therefore, it is a major challenge to correlate the emotional state of touch gestures with text responses. At present, there are few researches on touch-text dialogue, and robots cannot respond to human tactile gestures with appropriate text, so touch-text-based human-robot interaction is not yet possible. To solve these problems, we first built a touch-text dialogue (TTD) corpus based on six basic emotions through experiments, which contains 1109 touch-text sample pairs. And then, we designed a supervised adversarial learning for touch-text answer (SATTA) model to realize the touch-text based human-robot interaction. The SATTA model correlates the data of text mode with that of touch mode by reducing the emotion discrimination loss in the public space and the feature difference between the sample pairs of two modes. At the same time, the feature representation is mapped into the label space to reduce the classification loss of samples. The experiment in the TTD corpus validates the proposed method.

Design and Implementation of Health and Risk Level Assessment for Socially Disadvantaged Patients

The platform developed in this study provides users with mental and physical health status monitoring services. Recently, it has been difficult for people with various respiratory diseases and mental health conditions to receive regular examinations/observation from specialized medical institutions. Therefore, in this study, because the need for the continuous health status measurement/monitoring of subjects was recognized, a device for constantly monitoring trends and changes in blood oxygen saturation was developed to ensure safety. Oxygen saturation below 90 indicates an emergency. In addition, we conducted a hypothesis test for analyzing the relationship between sensor data and depression and anxiety. The sensor data used in the research were location, gyroscope metrics, touch, data usage, and sleep mode from a smartphone. Correlation analysis and multiple regression analysis were conducted to analyze the relationship between the collected sensor data and depression and anxiety. As a result of the research, it was found that among the general characteristics, income, location, sleep duration, and gyroscope were found to have a negative effect on depression and anxiety, whereas touch was shown to have a positive (+) effect. It was confirmed that sensor data measured over runtime can be used as information that can explain users’ depression and anxiety.

Research on a capacitive MEMS pressure sensor based on through glass via

AbstractThe paper reports the fabrication and characterization of a capacitive Microelectro Mechanical Systems pressure sensor based on through glass vias (TGV), which had a large dynamic range by operating in touch mode. The substrate with TGV offers the advantage of elimination of parasitic capacitances owing to the superior insulation property of glass. The fabrication process was introduced. In particular, anodic bonding was applied in high vacuum to realize the hermetic package to obtain large operating range and high sensitivity. The performance of the sensor with a sensitive diaphragm of 700 μm × 1400 μm was characterized in the pressure range from −80 to 180 kPa. The sensitivity was determined as 0.072 pF/kPa over the range of 160 kPa with a good linearity of 97%.

Means of expressing perception in the writer’s idiostyle: Mikhail Prishvin

M.M. Prishvin's idiostyle includes a universal component + a national-cultural component + an individual perception. M. Prishvin's picture of the world is, first of all, dynamic, filled with various sounds (sound and hearing are conveyed by verbs, verb forms, onomatopoeic words) and colored. The modes of taste, smell and touch are very important, but not paramount. Of course, such conclusions are made only on the basis of the analysis of one work of the writer, much in such studies depends on the plot and, of course, on the volume of the analyzed material.

Design and Simulation of PDMS and PMMA Based Touch Mode Capacitive Pressure Sensor: A Comparative Study

Aims: In this research work, a design method and a comparative of a touch mode capacitive pressure sensor (TMCPS) using poly-dimethyl-siloxane (PDMS) and poly-methyl methacrylate (PMMA) is the done. A novel method is proposed to linear the output characteristics of the sensor because planer type capacitive sensors are non-linear.
 Study Design: This method uses a mechanical coupler to convert the deflection of the diaphragm into a linear displacement that helps to linear the output characteristics. The mathematical model of the sensor is designed and simulated the 3D model to validate the mathematically calculated values.
 Place and Duration of Study: This study is done in the Department of Electronics and Communication Engineering, Rajiv Gandhi University, Arunachal Pradesh at COMSOL Simulation Laboratory during 2021 to 2023.
 Methodology: The mechanical and electrostatic components of the sensor are represented mathematically model in two separate parts. For this study, a square diaphragm was used since it exhibits greater deflection than circular or rectangular diaphragms. In order to validate the model equation, a 3D model of a sensor is created in the COMSOL Multiphysics simulator and simulated. For the pressure range of 0.1 [MPa] to 10.1 [MPa], the identical 3D model of the sensor construction with a square diaphragm thickness of 20 µm is simulated for PDMS and PMMA. The different elements influencing the sensor's sensitivity are discovered, and the effects of the materials PDMS and PMMA on the output characteristic are discussed.
 Results: The simulated and calculated sensitivity of the sensors based on PDMS are 0.03685 [fF/MPa] and 0.03467 [fF/MPa] respectively. And the simulated and calculated sensitivity of the sensors based on PMMA are 0.03929 [fF/MPa] and 0.03748 [fF/MPa] respectively. It is observed that the PDMS based TMCPS has more sensitivity then the PMMA based TMCPS.
 Conclusion: The PMMA based TMCPS has higher sensitivity than the PDMS based TMCPS. The various parameters that affect the sensitivity of the sensor are diaphragm shape, size, Poisson’s ratio and Young’s modulus, area covered by the dielectric material, dielectric constant of the polymers dielectric and surface are of the electrode plate.
 Future Scope: Future research for TMCPS can be conducted using composite polymer dielectric materials and new polymer dielectric materials to improve the sensitivity. One can optimize the sensor using different tools as the mathematical model is developed.

15Theatre and Performance

Abstract It’s a cliché, of course, to open an annual review by pointing out how the texts under discussion reflect our contemporary moment. And none of the books reviewed here are modish responses to passing scholarly fads. All speak first and foremost to concerns located at the very heart of the theatre medium itself: the imaginative construction of alternative shared worlds, and the exploration of our hopes and fears around modes of interpersonal touch and intimacy. So, forgive me just one brief reflection on how it is surely no coincidence that the books that intervene most excitingly and meaningfully in the scholarly field this year are also those that speak to some of the most pressing anxieties and desires in the broader world as well, in the wake of pandemic contagion, the #MeToo movement, a cost-of-living crisis, and continued dystopic crises in both the academic industry and in national and global politics. The first section of this chapter, ‘Utopia’, reviews three monographs that discuss the intersections between theatre, concepts of utopia and utopian thinking: Siân Adiseshiah’s Utopian Drama: In Search of a Genre, Selina’s Busby’s Applied Theatre: A Pedagogy of Utopia and Ryan Claycomb’s In the Lurch: Verbatim Theater and the Crisis of Democratic Deliberation. The second section, ‘Touch and Intimacy’, reviews two books that cast an eye on questions of touch and intimacy onstage, from a contemporary practice-based and historical scholarly perspective respectively: Supporting Staged Intimacy: A Practical Guide for Theatre Creatives, Managers, and Crew, co-authored by Alexis Black and Tina M. Newhauser, and Alex MacConochie’s Staging Touch in Shakespeare’s England.

Formulation Analysis and Follow-Up Study of Differential MEMS Touch-Mode Sensor Utilizing Capacitive Vacuum Gauge Framework for Low-Pressure Measurements

Differential capacitance diaphragm gauges have become more popular in pressure measurements as they yield superior sensitivity and lesser non-linearity for pressure differential measurements. In addition, differential capacitance diaphragm gauges do not require a high vacuum reference cavity which reduces their manufacturing complexity. Efficient analysis for modelling differential capacitance diaphragm gauges is thus increasingly becoming vital due to their innumerable use cases. The higher sensitivity of circular diaphragm for the same side length in comparison to square diaphragm makes it ideal for sensor design. In this work, a complete formulation for analysis of differential capacitive vacuum gauge with the circular diaphragm in normal and touch mode operation has been presented for the low-pressure range of (1 to 1500 pascals). A comprehensive study of sensor parameters like capacitance, diaphragm deflection, capacitive and mechanical sensitivity has been formulated to aid the choice of sensor characteristics. Computationally complex methods have been used in the past for analysis of circular diaphragms. MATLAB and COMSOL have been used to compute and simulate results.

A sensitivity enhanced touch mode capacitive pressure sensor with double cavities

A sensitivity enhanced touch mode capacitive pressure sensor with double cavities

Motion and Memory in VR: The Influence of VR Control Method on Memorization of Foreign Language Orthography

A small-scale investigation of 22 first-time VR users was conducted to determine the extent to which different control methods (“Touch Mode” and “Point Mode”) influenced participants’ ability to memorize the educational content (Hebrew orthography) in an original VR game. In Touch Mode, participants selected user interface (UI) elements by physically moving their hands (and upper bodies) toward targets in virtual space, whereas in Point Mode, participants could manipulate a virtual laser pointer with their wrists to select UI targets from a stationary position. The Point Mode control method required less time to learn on average than the Touch Mode with high-medium effect size (Cohen’s d = 0.76). Ultimately, the difference in post-test scores between Touch Mode users and Point Mode users was not statistically significant (p = .294). Thus, the increased bodily motion necessitated by Touch Mode did not have a significant influence on memory function as initially hypothesized.

Switch mode capacitive pressure sensors

Switch mode capacitive pressure sensors are proposed as a new class of microfabricated devices that transform pressure into a mechanically switching capacitance to form an analog-to-digital signal with zero power, high sensitivity, and a high signal-to-noise ratio. A pressure-sensitive gold membrane suspended over a capacitive cavity makes ohmic contact with patterned gold leads on the substrate, closing circuits to fixed on-chip capacitors outside the cavity and leading to significant step responses. This function is achieved by allocating the switch leads on the part of the counter electrode area, while the remaining area is used for touch mode analog capacitive sensing. The sensor microchip is prototyped through a novel design approach to surface micromachining that integrates micro-Tesla valves for vacuum sealing the sensor cavity, showing an unprecedented response to applied pressure. For a gauge pressure range of 0–120 mmHg, the sensor exhibits an increase of 13.21 pF with resultant switch events, each of which ranges from 2.53–3.96 pF every 12–38 mmHg, in addition to the touch mode linear capacitive increase between switches. The equivalent sensitivity is 80–240 fF/mmHg, which is 11–600× more than commercial and reported touch mode sensors operating in similar pressure ranges. The sensor is further demonstrated for wireless pressure tracking by creating a resonant tank with the sensor, showing a 32.5–101.6 kHz/mmHg sensitivity with frequency jumps led by the switch events. The developed sensor, with its promising performance, offers new application opportunities in a variety of device areas, including health care, robotics, industrial control, and environmental monitoring.

Evaluation of the visual-manual resources required to perform calling and navigation tasks in conventional mode with a portable phone and in full- touch mode with an embedded system

This study investigates the differences in a driver’s visual-manual behavior when performing secondary tasks while driving under the full-touch mode (FTM) and the conventional mode (CM). To this end, 30 participants were recruited to perform secondary tasks while driving two vehicles equipped with different HMI system interaction modes. The results show that compared to the CM, in the FTM, fewer visual-manual resources are required to perform the calling task, but for the navigation task, this requirement is higher. Additionally, in both modes, the driver exhibited self-regulation visual-manual behavior when performing secondary tasks as the driving speed increased. However, the effect of the driving speed on visual-manual behavior was greater in the FTM than in the CM. The main limitation of this study is that the effect of the difference between the two experimental vehicles on the findings was not considered, however, this does not affect the generalization of the findings.

Design and Analysis of a Novel MEMS Touch Mode Convex Capacitive Pressure Sensor for Altimeter Applications

The wide applications of Touch Mode Capacitive Pressure Sensors (TMCPS) have led the researchers working more on its performances. TMCPS have more acceptance due to their linearity, sensitivity, and ability to withstand more pressure which make them suitable for harsh environments. This study proposes a novel convex shape substrate to further improve the response of the TMCPS. This work provides a detailed mathematical and analytical modeling which upholds the proposed design. The analysis is compared with the simulation results from the software MATLAB. The simulated results have been compared with those reported in the existing literature. The linear operation range of the sensor is stretched more on the lower side (88[Formula: see text]KPa–2[Formula: see text]MPa) and the sensitivity is improved 2.85 times in touch mode, which completely fits in for the altimeter applications. This work also includes a detailed step-by-step process to be followed during the fabrication of the sensor. Sensor system characteristics such as nonlinearity, hysteresis and temperature dependence are also calculated in this work. The presented theory and simulation analysis fully supports the superior performance of the novel convex substrate square diaphragm TMCPS.

Understanding Influence of Substrate Floor Concavity on Sensitivity and Linearity Through a Parabolic Model: Theoretical Modeling and Analysis of Performance

These microelectromechanical system (MEMS)-based touch mode capacitive pressure sensors (TMCPSs) are popular because of their linear sensor output and mechanical robustness. In this work, we propose a parabolic well substrate TMCPS with a circular diaphragm. The proposed design is modeled mathematically, analyzed, and simulated using MATLAB. The diaphragm of the sensor is modeled using a small deflection model. The sensor is intended to operate until a pressure of 2 MPa. The analysis and simulations indicate an improvement in linearity and sensitivity of the sensor output in the touch mode of operation. The analysis and modeling of the proposed design will be useful for designing TMCPS for performance improvement and understanding its behavior. An analysis of the influence of the sensor substrate’s concavity on the sensitivity and linearity of the sensor’s output is discussed in this work.

Polymer Conductive Membrane-Based Circular Capacitive Pressure Sensors from Non-Touch Mode of Operation to Touch Mode of Operation: An Analytical Solution-Based Method for Design and Numerical Calibration.

Polymer-based conductive membranes play an important role in the development of elastic deflection-based pressure sensors. In this paper, an analytical solution-based method is presented for the design and numerical calibration of polymer conductive membrane-based circular capacitive pressure sensors from non-touch mode of operation to touch mode of operation. The contact problem of a circular membrane in frictionless contact with a rigid flat plate under pressure is analytically solved, and its analytical solution is used for the design of touch mode circular capacitive pressure sensors for the first time. The analytical relationship with input pressure as independent variable and output capacitance as dependent variable is precisely derived and is used for the numerical calibrations of the analytical relationships with input capacitance as the independent variable and output pressure as the dependent variable in order to meet the capacitive pressure sensor mechanism of detecting pressure by measuring capacitance. For the first time, an example showing the design and numerical calibration of a given (given design parameters) polymer conductive membrane-based circular capacitive pressure sensor from non-touch mode of operation to touch mode of operation is provided. Then, the influence of changing several important design parameters on input capacitance–output pressure relationships is comprehensively investigated in order to clarify the desired input–output relationships when changing design parameters.

Efficient in-depth analysis and optimum design parameter estimation of MEMS capacitive pressure sensor utilizing analytical approach for square diaphragm

Capacitive pressure sensors have become more popular as compared to piezoresistive pressure sensors as they yield superior sensitivity and lesser nonlinearity. Efficient analysis for modeling capacitive pressure sensors is thus increasingly becoming more important due to their innumerable use cases. The higher sensitivity of square diaphragm for the same side length in comparison to circular diaphragm makes it ideal for sensor design. In this work, a complete formulation for analysis of capacitive pressure sensor with the square diaphragm in normal and touch mode operation has been presented as these two modes are established operating modes for these sensors. A comprehensive study of sensor parameters like capacitance, diaphragm deflection, capacitive and mechanical sensitivity has been formulated to aid the choice of sensor characteristics. This work also focuses on the method to determine core design parameters for optimal operation. Computationally complex methods have been used in the past for analysis of square diaphragms. The analytical approach presented in this research is less complex and computationally efficient, in comparison to the finite element method. MATLAB has been used to compute and simulate results.