Measurement method and measurement apparatus

Patent metadata

Field	Value
Publication number	US-11906374-B2
Application number	US-201917015302-A
Country	US
Kind code	B2
Filing date	Feb 6, 2019
Priority date	Mar 9, 2018
Publication date	Feb 20, 2024
Grant date	Feb 20, 2024

Abstract

Provided is a measurement method including measuring, by using a piezoelectric sheet sensor in contact with a measurement object, vibration transmitted from the measurement object to the piezoelectric sheet sensor and measuring pressing force between the measurement object and the piezoelectric sheet sensor.

First claim

What is claimed is:

1. A measurement method, comprising:
measuring, by using a piezoelectric sheet sensor in contact with a measurement object, vibration transmitted from the measurement object to the piezoelectric sheet sensor; and
measuring a pressing force between the measurement object and the piezoelectric sheet sensor, wherein
in the measuring of the pressing force, the pressing force between the measurement object and the piezoelectric sheet sensor is measured based on a signal generated between a pressing force measurement electrode arranged on a first surface of a sheet-like piezoelectric body and a second electrode arranged on a second surface of the sheet-like piezoelectric body,
in the measuring of the vibration, the vibration transmitted from the measurement object to the piezoelectric sheet sensor is detected based on a signal generated between a vibration measurement electrode arranged on the first surface of the sheet-like piezoelectric body and the second electrode, and
the pressing force measurement electrode is electrically separated from the vibration measurement electrode.

2. The measurement method according to claim 1 , wherein a first period in which the vibration is measured in the measuring of the vibration is not overlapping a second period in which the pressing force is measured in the measuring of the pressing force.

3. The measurement method according to claim 1 , further comprising determining whether a magnitude of the pressing force measured in the measuring of the pressing force is a predetermined magnitude, wherein, based on the determination that the magnitude of the pressing force measured is the predetermined magnitude, the measuring of the pressing force is finished, and the measuring of the vibration is started.

4. The measurement method according to claim 1 , wherein,
in the measuring of the pressing force, the pressing force between the measurement object and the piezoelectric sheet sensor is measured based on a first signal generated between a first electrode arranged on the first surface of the sheet-like piezoelectric body and the second electrode arranged on the second surface of the sheet-like piezoelectric body, and
in the measuring of the vibration, the vibration transmitted from the measurement object to the piezoelectric sheet sensor is detected based on a second signal generated between the first electrode and the second electrode.

5. The measurement method according to claim 1 , wherein a first period in which the vibration is measured in the measuring of the vibration at least partially overlaps a second period in which the pressing force is measured in the measuring of the pressing force.

6. The measurement method according to claim 1 , further comprising controlling one or more switches, connected to the piezoelectric sheet sensor, to alternately perform the measurement of the vibration and the measurement of the pressing force.

7. The measurement method according to claim 1 , further comprising:
adjusting the pressing force between the measurement object and the piezoelectric sheet sensor, based on the measured pressing force; and
measuring the vibration transmitted from the measurement object and the piezoelectric sheet sensor subsequent to the adjustment.

8. A measurement apparatus, comprising:
a piezoelectric sheet sensor configured to come into contact with a measurement object; and
a measurement control unit configured to use the piezoelectric sheet sensor to measure vibration transmitted from the measurement object to the piezoelectric sheet sensor and a pressing force between the measurement object and the piezoelectric sheet sensor, wherein
in the measurement of the pressing force, the pressing force between the measurement object and the piezoelectric sheet sensor is measured based on a signal generated between a pressing force measurement electrode arranged on a first surface of a sheet-like piezoelectric body and a second electrode arranged on a second surface of the sheet-like piezoelectric body,
in the measurement of the vibration, the vibration transmitted from the measurement object to the piezoelectric sheet sensor is detected based on a signal generated between a vibration measurement electrode arranged on the first surface of the sheet-like piezoelectric body and the second electrode, and
the pressing force measurement electrode is electrically separated from the vibration measurement electrode.

9. The measurement apparatus according to claim 8 , wherein the measurement control unit is further configured to measure the pressing force in a first period and measure the vibration in a second period not overlapping the first period.

10. The measurement apparatus according to claim 9 , wherein
the piezoelectric sheet sensor includes the sheet-like piezoelectric body, a first electrode arranged on the first surface of the sheet-like piezoelectric body, and the second electrode arranged on the second surface of the sheet-like piezoelectric body, and
the measurement control unit is further configured to apply an alternating current voltage between the first electrode and the second electrode to detect the pressing force.

11. The measurement apparatus according to claim 10 , wherein the measurement control unit is further configured to:
measure the pressing force between the measurement object and the piezoelectric sheet sensor, based on a first signal generated between the first electrode and the second electrode; and
measure the vibration transmitted from the measurement object to the piezoelectric sheet sensor, based on a second signal generated between the first electrode and the second electrode.

12. The measurement apparatus according to claim 9 , further comprising a switch control unit configured to control one or more switches to sequentially switch the measurement of the pressing force and the measurement of the vibration.

13. The measurement apparatus according to claim 8 , wherein the measurement control unit is further configured to:
apply an alternating current signal to acquire a signal indicating a change in a resonance frequency of the piezoelectric sheet sensor; and
measure the pressing force between the measurement object and the piezoelectric sheet sensor, based on the acquired signal.

14. The measurement apparatus according to claim 8 , further comprising a pressing force control unit configured to adjust the pressing force between the measurement object and the piezoelectric sheet sensor, based on the measured pressing force.

15. The measurement apparatus according to claim 8 , further comprising a pressing force generation unit configured to generate the pressing force between the measurement object and the piezoelectric sheet sensor.

16. A piezoelectric sheet sensor, comprising:
a vibration measurement electrode and a pressing force measurement electrode arranged on a same side of a common sheet-like piezoelectric body, wherein
the vibration measurement electrode is electrically separated from the pressing force measurement electrode, and
a first period for measuring a vibration at least partially overlaps a second period for measuring pressing force.

Assignees

• Yamaha Corp

Inventors

• Miyata Tomoya

Classifications

• G01L1/167 Primary

  optical excitation or measuring of vibrations · CPC title

• G01H11/08

  using piezoelectric devices · CPC title

• G01L1/103

  optical excitation or measuring of vibrations · CPC title

• G01L1/10 Primary

  by measuring variations of frequency of stressed vibrating elements, e.g. of stressed strings (using resistance strain gauges G01L1/22) · CPC title

• A61B5/11

  Measuring movement of the entire body or parts thereof, e.g. head or hand tremor or mobility of a limb {(A61B5/1038 takes precedence; motion detection to correct for motion artifacts in physiological signals A61B5/721)} · CPC title