Wireless Strain Monitoring Research Articles

Passive Wireless Strain Monitoring of Actual Tire using Tuning Circuit and Spectral Features

To improve the reliability of automobile tires and anti-lock braking system (ABS), smart tires that measure strain of tires are increasingly demanded. The high stiffness of an embedded sensor like a strain gage, however, causes debonding of sensors from tire rubber. In a previous study, the authors proposed a tire strain monitoring method that adopts the tire itself as a sensor with a tuning circuit.Since the deformation of a rectangular specimen used, however, is different from that of an actual tire, the tuning frequency does not change linearly with the strain change of an actual tire. In the present study, the monitoring system with a tuning circuit is applied to an actual radial tire using spectral features of peak spectrum and quality factor as well as tuning frequency to improve the accuracy of strain estimation. As a result, the method is experimentally proved to be effective for the passive wireless strain monitoring of actual radial tires.

Wireless strain monitoring of tires using electrical capacitance changes with an oscillating circuit

In-service strain monitoring of automobile tires is quite effective to improve reliability of tires and design tools. Conventional strain gages have high stiffness and require lead wires. For those reasons, they are cumbersome for strain measurement of tires. Therefore, a new low cost wireless sensor is required for tires. The present study proposes and experimentally investigates a new wireless strain measurement system using the electric capacitance change of steel-wire reinforced tires. A small CR oscillating circuit is embedded in the tire. Thereby, tire deformation engenders a capacitance change of the tire, which comprises steel wire and rubber. In turn, these changes in capacitance alter the oscillating frequency of the oscillating circuit. Measurement of the oscillating circuit frequency indicates the tire strain wirelessly. A rectangular specimen cut from a truck tire is adopted as a specimen for this study. Finally, feasibility of the proposed system is examined using a commercially available passenger car tire through performing static compression and a dynamic rotation test. Experimental results prove that the method is effective for wireless strain monitoring of tires.

タイヤの電気容量と電磁誘導変化を用いたひずみ無線パッシブモニタリング

Strain monitoring of automobile tires in-service is quite effective for improving the reliability of tires and ABS (Anti-lock Braking System). In a previous study, the authors proposed a new wireless strain monitoring method which is adopted in the tire itself as a sensor with an oscillator circuit. This method is simple and useful, but it requires a battery to activate the oscillator circuit. In the present study, a new passive wireless strain measurement system utilizing capacitance change of tires is proposed and experimentally investigated. The system consists of external antennas and strain sensor with an inductance-capacitance (LC) resonant circuit. The wireless system utilizes electromagnetic coupling between two inductors of the antenna and the sensor. This method enables us to use a part of an actual tire as a capacitor of the LC circuit. Deformation of the tire causes a resonant frequency change of the sensor. This resonant frequency change is measured as a change in the phase angle of the antenna by using electromagnetic induction. Tensile tests are performed and the phase angles are simultaneously measured. As a result, the method is experimentally shown to be effective as a passive wireless strain monitoring of tires.

スマートタイヤ用無線パッシブひずみモニタリング(OS1-4 機器・金属,OS1 構造ヘルスモニタリング)

スマートタイヤ用無線パッシブひずみモニタリング(OS1-4 機器・金属,OS1 構造ヘルスモニタリング)

タイヤの電気容量変化と発振回路を用いたひずみ無線モニタリング

The strain monitoring of automobile tires in-service is quite effective to improve reliability of tires and design tools. The conventional strain gages are cumbersome for the strain measurement of the tires because of their high stiffness and lead wire requirement. In the present study, a new strain measurement system utilize electric capacitance change of steel wire reinforced, low cost wireless sensor built-in tires is proposed and experimentally investigated. A small oscillating circuit in which the capacitor is composed with the rubber and the wire is embedded in the tire, then deformation of the tire causes change of the capacitance makes change of frequency. Measurement of the frequency enables us a remote measuring of the strain of the tire. A rectangular specimen cut from a truck tire is adopted as a specimen. Using the commercially available tire in which sensor embedded, dynamic test is performed and frequency change of the oscillating circuit is measured during the test. As a result, the method is experimentally proved to be effective for the wireless strain monitoring of tires.

タイヤの電気容量と同調周波数変化を用いたひずみ無線パッシブモニタリング(モニタリング,OS.6 折り紙・針金/スマートストラクチャ)

Safety of automobiles is increasingly demanded. To prevent burst of tires, smart tires are currently under development The embedded sensor enables highly precise measurement of road surface friction, and the precise friction measurements make more efficient anti-blocking-system (ABS). In a previous study, the authors proposed a new wireless strain monitoring method that adopts the tire itself as a sensor, with an oscillator circuit. This method is very simple and useful, but it requires a battery to activate the oscillator circuit. In the present study, the previous method for wireless tire monitoring is improved to produce a passive wireless sensor. The capacitance change of tire causes changes of the tuning frequency. This change of the tuned radio wave enables us to measure the applied strain of the specimen wirelessly, without any power supply from outside. This new passive wireless method is applied to a specimen and the static applied strain is measured.

Wireless strain monitoring using electrical capacitance change of tire:part II—passive

In-service strain monitoring of tires of automobiles is quite effective for improvingthe reliability of tires and design tools. In a previous study, the authors proposeda new wireless strain monitoring method that adopts the tire itself as a sensor,with an oscillator circuit. In the method, steel wires are employed as electrodes tomeasure electrical capacitance changes of tires. A specimen cut from acommercial tire is connected to an oscillator circuit, and the oscillationfrequency changes with the capacitance changes of the tire. This method isvery simple and useful, but it requires a battery to activate the oscillatorcircuit. In the present study, a new passive strain measurement systemutilizing electrical capacitance changes of steel-wire-reinforced tires isproposed and experimentally investigated. The passive wireless strainmonitoring method makes use of the specimen cut from the tire as acondenser of a passive filter circuit. Deformation of the tire causes capacitancechanges of the tire comprised of steel wire and rubber; the change of thecapacitance causes a change of the filtering frequency of a radio wave.Measurement of the frequency of a radio wave passed through the filtercircuit enables us to measure the strain of the tire wirelessly. A rectangularspecimen cut from a commercially available tire is adopted as a specimen.Tension testing is performed and the change of the filtering frequencyis measured during the test. As a result, the method is experimentallyproved to be effective for the passive wireless strain monitoring of tires.

Wireless strain monitoring usingelectrical capacitance change of tire: part I—with oscillating circuit

Strain monitoring of tires of automobiles in service is quite effective to improvethe reliability of tires and design tools. Since conventional strain gages have highstiffness and require lead wires, the conventional strain gages are cumbersomefor the strain measurement of tires. Sensors of micro-electro-mechanicalsystems are also usually of high stiffness themselves, and those are notapplied to tires. The background requires a new low cost wireless sensor fortires. In the present study, a new strain measurement system utilizing theelectric capacitance change of steel wire reinforced tires is proposed andexperimentally investigated. A small oscillating circuit is embedded inthe tire; deformation of the tire induces a capacitance change of the tirecomprising steel wire and rubber; the change of the capacitance makes a changein oscillating frequency of the oscillating circuit. Measurement of thefrequency of the oscillating circuit enables us to measure the strain of the tirewirelessly. A rectangular specimen cut from a commercially available tire isadopted as a specimen. A tension test is performed and the frequency of theoscillating circuit is measured during the test. As a result, the method isexperimentally proved to be effective for the wireless strain monitoring of tires.

1322 タイヤの無線ひずみモニタリングシステム

1322 タイヤの無線ひずみモニタリングシステム

660 タイヤ構造の電気容量変化を利用した無線ひずみモニタリング

Strain monitoring of tires of automobiles in-service is quite effective to improve reliability of tires and design tools. In the previous study, authors have proposed a new wireless strain monitoring method that adopts a tire itself as a sensor with an oscillator circuit. In the present study, a new passive strain measurement system utilize electric capacitance change of steel wire reinforced tires is proposed and experimentally investigated. The passive wireless strain monitoring method makes use of the specimen cut from the tire as a condenser of a passive filter circuit. Deformation of the tire brings capacitance change of the tire comprises steel wire and rubber; the change of the capacitance makes the change of filtering frequency of radio wave. Measurement of the frequency of radio wave passed through the filter circuit enables us to measure the strain of the tire wirelessly. A rectangular specimen cut from a commercially available tire is adopted as a specimen. Tension test is performed and the change of filtering capacity is measured during the test. As a result, the method is experimentally proved to be effective for the passive wireless strain monitoring of tires.

K-2328 複合材料のインピーダンス変化を利用したひずみのワイヤレスモニタリング(J03-6 ヘルスモニタリング)(J03 知的材料・構造システム)

Strain monitoring for composite materials in-service is quite effective to improve structural reliability of composite materials. Recently, it is demanded to monitor strain of tire structure in service. The MEMS is one of the solutions for the wireless monitoring. However, the MEMS has high stiffness and has problem for attachment for flexible structures such as rubber tires. In the present study, therefore, a new technology using impedance change of composite materials for strain monitoring system. The present study, show the applicability of strain measurements with the electric impedance change due to deformation of composite materials experimentally.