Construction of a New Flat Force Sensor Using the Resonant Frequency Shift by Axial Force

Self Cite

We describe an acceleration sensor composed of four vibration bars, with a detection mechanism in which the resonant frequencies of the four bars are brought close together. The bars are connected mechanically at the center, and a cross-shaped layout is used such that for any load direction, the sizes of the loads on the vibration bars mutually oppose each other. Using this structure, acceleration can be easily calculated by differential detection of the oscillation amplitude signals of each of the four vibration bars. The body of the sensor is made of stainless steel (SUS304). The volume of the experimental sample is about 76 ×76 ×8 mm3, and the resonance frequency and quality factor are about 1041 Hz and 87, respectively. The sensor characteristics are measured using the gravitational field, and the acceleration is changed by rotating the sensor around the axis along the length of the vibrator.

Section: ------------------------------------------------------------mentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Construction of Two-Axis Acceleration Sensor Using a Cross-Coupled Vibrator

Terada

Uetsuji

Sugawara

2012

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“…Then, the structures of one-and two-axis acceleration sensors were proposed, and investigated experimentally. [1][2][3][4][5][6][7][8] But, the characteristics of the two-axis sensor shoud be improved on the point that an signal from the other axis is detected. 9) As this reason, it is clarified that mass of the sensor rotates by acceleration in the plane.…”

Section: Introductionmentioning

confidence: 99%

Improvement of Characteristics of Frequency-Change-Type Two-Axis Acceleration Sensor

Sugawara¹,

Kajiwara²

2012

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The characteristics of a frequency-change-type two-axis acceleration sensor must be improved on the point that an undesirable signal from the other axis direction is detected. The signal is caused by the rotation of mass in the sensor. Two methods for improving the characteristics are proposed here and investigated by finite-element analysis. First, the center of gravity in the sensor was moved to realize a linear motion of mass. As a result, the signal became very small from 5.1 to 0.4%, but the volume of the sensor increased by 28%. Next, the other method of adjusting the dimensions of a bent-type support bar was proposed to realize a linear motion of mass. The rotation was not observed when the signal was decreased to almost zero. The method is very useful from the standpoint of realizing the same volume as the sensor of the prototype.

“…To develop such a sensor, the authors have studied an acceleration sensor that utilizes the phenomenon that the resonance frequency of a bending vibrator changes by the axial force. [1][2][3][4][5][6][7][8][9][10][11] As one example of these sensors the sensor using a coupled bending vibrator was also proposed. 12) However, the characteristics of this vibrator were not clarified sufficiently.…”

Section: Introductionmentioning

confidence: 99%

“…1(a) shows the vibration mode of the bending vibrator. 2) Displacements at both ends of the vibrator are designed so as to become very small. Fig.…”

Section: Introductionmentioning

confidence: 99%

Analysis of Characteristics of Coupled Bending Vibrators Used as a Force Sensor

Sugawara

Terada

Takahashi

2012

Self Cite

The characteristics of the coupled bending vibrator that linearly connects the two bending vibrators are analyzed by the finite-element method, and then the characteristics of the coupled bending vibrator used as a force sensor are investigated. The coupled bending vibrator is applied to an acceleration sensor as a force sensor. The vibration mode in which the two vibrators of the coupled vibrator are out of phase is used here and is very stable because it does not couple with other vibration modes. When the axial force is applied, the amplitude of one vibrator of the coupled vibrator decreases with increase in compressive force. The amplitude of the other vibrator also decreases when the force is applied in the opposite direction. Therefore, the coupled vibrator is used as a force sensor that can estimate the axial force as a change in the amplitude of the vibrator.