A Disturbance Suppression Micro-Newton Force Sensor Based on Shadow Method

<div>The precision of micro-force measurement is determined by the sensitivity of force sensors and the magnitude of environmental disturbances. Damping, a process that converts vibrational energy into heat, is one of the most effective methods of suppressing disturbances. Inspired by the shadow formed at a pond when water striders walked on the water, a bionic viscoelastic-polymer micro-force (VPMF) sensor with a high damping ratio based on the shadow method was developed. In the VPMF sensor, the surface of the polymer was deformed by the contact of a cylindrical flat punch when the sensor was subjected to a normal force. A shadow with a bright edge was formed due to the refraction that parallel light went through the deformed surface. The force was in proportion to the change of the shadow diameter. The sensor optimal sensitivity was 2.15 μN/pixel and the measurement range was 0.981 mN. The damping ratio of the VPMF sensor was 0.22 on account of viscoelasticity, which could suppress disturbances effectively. The VPMF sensor could reduce the influence of disturbances by about 96.23% compared to the cantilever. The present study suggests that the VPMF sensor is hopefully applied to the reliable measurement of micro force under complex environments.</div>

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Force sensor with increased local resolution for electronic Contact Normal Force measurement in electrical connectors

2019 IEEE SENSORS ◽

10.1109/sensors43011.2019.8956630 ◽

2019 ◽

Author(s):

Felix Greiner ◽

Romol Chadda ◽

Jan-Eric Adolf ◽

Sebastian Beck ◽

Mario Kupnik

Keyword(s):

Normal Force ◽

Force Measurement ◽

Force Sensor ◽

Electrical Connectors

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New Giant Magnetostrictive Force Sensors

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.816-817.424 ◽

2013 ◽

Vol 816-817 ◽

pp. 424-428

Author(s):

Rong Ge Yan ◽

Li Hua Zhu ◽

Qing Xin Yang

Keyword(s):

Force Measurement ◽

Force Sensor ◽

Measurement Range ◽

Magnetic Flux Density ◽

Force Sensors ◽

Dynamic Force ◽

Element Analysis ◽

Giant Magnetostrictive Materials ◽

Overload Capacity ◽

Adjustable Range

Force sensors, based on the giant inverse magnetostrictive effect, have a series of outstanding properties, such as large overload capacity, which make them have more and more applications to the field of automatic control system of heavy industry, chemical industry. This paper designs new giant magnetostrictive force sensors using the rare-earth iron giant magnetostrictive materials. With the designed giant magnetostrictive force sensor, the relations between magnetic flux density in the gap and applied static stress on the sensor, the inductive voltage in the coil and time (with the dynamic stress), are calculated by finite element analysis software. The related confirmatory experiments have been conducted. The experimental results indicate that the giant magnetostrictive force sensor is fit for static and dynamic force measurement. In order to enlarge the measurement range, the designed force sensor as the basic cell is combined. This paper gives two kinds of combinations, which have the feature of adjustable range.

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Characterization of Variable-sensitivity Compact Force Sensor using Stiffness Change of Shape-memory Polymer Based on Temperature

10.21203/rs.3.rs-613679/v1 ◽

2021 ◽

Author(s):

Kazuto Takashima ◽

Jo Kobuchi ◽

Norihiro Kamamichi ◽

Kentaro Takagi ◽

Toshiharu Mukai

Keyword(s):

Transfer Function ◽

Shape Memory ◽

Force Measurement ◽

Shape Memory Polymer ◽

Viscoelastic Behavior ◽

Force Sensor ◽

Measurement Range ◽

Applied Force ◽

Soft Phase ◽

Variable Sensitivity

Abstract In the present study, we propose a variable-sensitivity force sensor using a shape-memory polymer (SMP), the stiffness of which varies according to the temperature. Since the measurement range and sensitivity can be changed, it is not necessary to replace the force sensor to match the measurement target. Shape-memory polymers are often described as two-phase structures comprising a lower-temperature “glassy” hard phase and a higher-temperature “rubbery” soft phase. The relationship between the applied force and the deformation of the SMP changes depending on the temperature. The proposed sensor consists of strain gauges bonded to an SMP bending beam and senses the applied force by measuring the strain. Therefore, the force measurement range and the sensitivity can be changed according to the temperature. In our previous study, we found that a sensor with one strain gauge and a steel plate had a small error and a large sensitivity range. Therefore, in the present study, we miniaturize this type of sensor. Moreover, in order to describe the viscoelastic behavior more accurately, we propose a transfer function using a generalized Maxwell model. We verify the proposed model experimentally and estimated the parameters by system identification. In addition, we realize miniaturization of the sensor and achieve the same performance as in our previous study. It is shown that the proposed transfer function can capture the viscoelastic behavior of the proposed SMP sensor quite well.

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Characterization of variable-sensitivity force sensor using stiffness change of shape-memory polymer based on temperature

ROBOMECH Journal ◽

10.1186/s40648-021-00210-8 ◽

2021 ◽

Vol 8 (1) ◽

Author(s):

Kazuto Takashima ◽

Jo Kobuchi ◽

Norihiro Kamamichi ◽

Kentaro Takagi ◽

Toshiharu Mukai

Keyword(s):

Transfer Function ◽

Shape Memory ◽

Force Measurement ◽

Shape Memory Polymer ◽

Viscoelastic Behavior ◽

Force Sensor ◽

Measurement Range ◽

Applied Force ◽

Soft Phase ◽

Variable Sensitivity

AbstractIn the present study, we propose a variable-sensitivity force sensor using a shape-memory polymer (SMP), the stiffness of which varies according to the temperature. Since the measurement range and sensitivity can be changed, it is not necessary to replace the force sensor to match the measurement target. Shape-memory polymers are often described as two-phase structures comprising a lower-temperature “glassy” hard phase and a higher-temperature “rubbery” soft phase. The relationship between the applied force and the deformation of the SMP changes depending on the temperature. The proposed sensor consists of strain gauges bonded to an SMP bending beam and senses the applied force by measuring the strain. Therefore, the force measurement range and the sensitivity can be changed according to the temperature. In our previous study, we found that a sensor with one strain gauge and a steel plate had a small error and a large sensitivity range. Therefore, in the present study, we miniaturize this type of sensor. Moreover, in order to describe the viscoelastic behavior more accurately, we propose a transfer function using a generalized Maxwell model. We verify the proposed model experimentally and estimated the parameters by system identification. In addition, we realize miniaturization of the sensor and achieve the same performance as in our previous study. It is shown that the proposed transfer function can capture the viscoelastic behavior of the proposed SMP sensor quite well.

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VirtualCPR: Virtual Reality Mobile Application for Training in Cardiopulmonary Resuscitation Techniques

Sensors ◽

10.3390/s21072504 ◽

2021 ◽

Vol 21 (7) ◽

pp. 2504

Author(s):

Francisco Javier García Fierros ◽

Jesús Jaime Moreno Escobar ◽

Gabriel Sepúlveda Cervantes ◽

Oswaldo Morales Matamoros ◽

Ricardo Tejeida Padilla

Keyword(s):

Virtual Reality ◽

Cardiopulmonary Resuscitation ◽

Mobile Application ◽

Force Measurement ◽

Heart Diseases ◽

Medical Knowledge ◽

Public Health Problem ◽

Force Sensor ◽

Previous Training ◽

Color Indicator

Deaths due to heart diseases are a leading cause of death in Mexico. Cardiovascular diseases are considered a public health problem because they produce cardiorespiratory arrests. During an arrest, cardiac and/or respiratory activity stops. A cardiorespiratory arrest is rapidly fatal without a quick and efficient intervention. As a response to this problem, the VirtualCPR system was designed in the present work. VirtualCPR is a mobile virtual reality application to support learning and practicing of basic techniques of cardiopulmonary resuscitation (CPR) for experts or non-experts in CPR. VirtualCPR implements an interactive virtual scenario with the user, which is visible by means of employment of virtual reality lenses. User’s interactions, with our proposal, are by a portable force sensor for integration with training mannequins, whose development is based on an application for the Android platform. Furthermore, this proposal integrates medical knowledge in first aid, related to the basic CPR for adults using only the hands, as well as technological knowledge, related to development of simulations on a mobile virtual reality platform by three main processes: (i) force measurement and conversion, (ii) data transmission and (iii) simulation of a virtual scenario. An experiment by means of a multifactorial analysis of variance was designed considering four factors for a CPR session: (i) previous training in CPR, (ii) frequency of compressions, (iii) presence of auditory suggestions and (iv) presence of color indicator. Our findings point out that the more previous training in CPR a user of the VirtualCPR system has, the greater the percentage of correct compressions obtained from a virtual CPR session. Setting the rate to 100 or 150 compressions per minute, turning on or off the auditory suggestions and turning the color indicator on or off during the session have no significant effect on the results obtained by the user.

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Static Force Measurement Using Piezoelectric Sensors

Journal of Sensors ◽

10.1155/2021/6664200 ◽

2021 ◽

Vol 2021 ◽

pp. 1-8

Author(s):

Kyungrim Kim ◽

Jinwook Kim ◽

Xiaoning Jiang ◽

Taeyang Kim

Keyword(s):

Surface Charge ◽

Piezoelectric Effect ◽

Force Measurement ◽

Piezoelectric Materials ◽

Force Sensor ◽

Piezoelectric Sensors ◽

Force Sensing ◽

Static Force ◽

Sensing Applications ◽

Direct Piezoelectric Effect

In force measurement applications, a piezoelectric force sensor is one of the most popular sensors due to its advantages of low cost, linear response, and high sensitivity. Piezoelectric sensors effectively convert dynamic forces to electrical signals by the direct piezoelectric effect, but their use has been limited in measuring static forces due to the easily neutralized surface charge. To overcome this shortcoming, several static (either pure static or quasistatic) force sensing techniques using piezoelectric materials have been developed utilizing several unique parameters rather than just the surface charge produced by an applied force. The parameters for static force measurement include the resonance frequency, electrical impedance, decay time constant, and capacitance. In this review, we discuss the detailed mechanism of these piezoelectric-type, static force sensing methods that use more than the direct piezoelectric effect. We also highlight the challenges and potentials of each method for static force sensing applications.

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Fingertip Force Measurement of GloveMAP by Using a Flexi Force Sensor

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.780.1 ◽

2015 ◽

Vol 780 ◽

pp. 1-5

Author(s):

Khairunizam Wan ◽

H.E. Nabilah ◽

Nor Farahiya ◽

M. Hazwan Ali ◽

Rashidah Suhaimi ◽

...

Keyword(s):

Force Measurement ◽

Current Trend ◽

Force Sensor ◽

Force Sensors ◽

Gaussian Filter ◽

Natural Interaction ◽

Fingertip Force ◽

Grasping Force ◽

Interface Devices ◽

A Current

Modernization of human technologies overtime results the need of more freedom technology likes the use of natural interaction to replace a current trend interface devices such as joysticks, mice, keyboards and other related output devices. Dataglove is one of the interface devices that could serve a natural interaction between user and computers. In this paper, a dataglove called GloveMAP is introduced which has the capability of measuring fingertip force. The flexible force sensors are attached to the fingers location of the glove. Several object grasping experiments are conducted and the grasping force signals are measured. A Gaussian filter is introduced to smoothen the acquired force signals.

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Evaluation of thin, flexible sensors for time-resolved grip force measurement

Proceedings of the Institution of Mechanical Engineers Part C Journal of Mechanical Engineering Science ◽

10.1243/09544062jmes700 ◽

2007 ◽

Vol 221 (12) ◽

pp. 1687-1699 ◽

Cited By ~ 42

Author(s):

E R Komi ◽

J R Roberts ◽

S J Rothberg

Keyword(s):

Shear Force ◽

Grip Force ◽

Force Measurement ◽

Real Life ◽

Force Sensor ◽

Ease Of Use ◽

Time Resolved ◽

Flexible Sensors ◽

Sensor Performance ◽

Dynamic Accuracy

Three types of thin, flexible force sensor were studied under a variety of loading conditions to determine their suitability for measuring grip force. Static accuracy, hysteresis, repeatability, and drift errors were established, the effects of shear force and surface curvature were considered, and dynamic accuracy and drift were measured. Novel tests were developed to consider dynamic accuracy and sensitivity to shear loadings. Additionally, three sensors were evaluated in a real-life gripping scenario, measuring grip force during a golf shot. Comments are made on sensor performance, ease of use, and durability.

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