US 12,146,855 B2
Internal state detector and vehicle
Taku Kondoh, Shizuoka (JP); Akihiro Chiba, Shizuoka (JP); Shota Tezuka, Shizuoka (JP); Yoji Okabe, Tokyo (JP); Osamu Saito, Tokyo (JP); and Peiwen Deng, Tokyo (JP)
Assigned to YAMAHA HATSUDOKI KABUSHIKI KAISHA, Iwata (JP); and THE UNIVERSITY OF TOKYO, Tokyo (JP)
Filed by YAMAHA HATSUDOKI KABUSHIKI KAISHA, Iwata (JP); and The University of Tokyo, Tokyo (JP)
Filed on Jul. 15, 2021, as Appl. No. 17/377,306.
Application 17/377,306 is a continuation in part of application No. PCT/JP2020/000332, filed on Jan. 8, 2020.
Claims priority of application No. 2019-004768 (JP), filed on Jan. 15, 2019.
Prior Publication US 2021/0341426 A1, Nov. 4, 2021
Int. Cl. G01N 29/04 (2006.01); G01N 29/07 (2006.01); G01N 29/24 (2006.01); G01N 29/34 (2006.01); G01N 29/44 (2006.01)
CPC G01N 29/041 (2013.01) [G01N 29/07 (2013.01); G01N 29/2437 (2013.01); G01N 29/348 (2013.01); G01N 29/4427 (2013.01); G01N 2291/011 (2013.01); G01N 2291/0231 (2013.01); G01N 2291/0258 (2013.01); G01N 2291/0289 (2013.01); G01N 2291/0423 (2013.01); G01N 2291/0427 (2013.01); G01N 2291/103 (2013.01)] 7 Claims
OG exemplary drawing
 
1. An internal state detector that detects an internal state of an object, the object being of a plate shape and including a fiber-reinforced resin, the internal state detector comprising:
an exciter that applies, to a surface of the object, ultrasonic vibrations of Lamb waves, including the ultrasonic vibrations in a selected frequency range where only a zero-order fundamental wave symmetric mode and a zero-order fundamental wave asymmetric mode of the Lamb waves appear, the selected frequency range including a plurality of frequencies;
a vibration detector that detects the ultrasonic vibrations of the Lamb waves applied by the exciter to the object and propagating in the object; and
an internal state estimation calculator that estimates the internal state of the object, based on a detection result of the vibration detector, the internal state estimation calculator being configured to
obtain a propagation time of the ultrasonic vibrations propagating in the object corresponding to each frequency of the Lamb waves, based on the detection result of the vibration detector obtained responsive to the vibration application by the exciter,
estimate the internal state of the object, based on a delay time of the propagation time relative to a reference propagation time of the object for each of the plurality of frequencies in the selected frequency range, and
output the estimated internal state, wherein
the internal state estimation calculator is configured to estimate the internal state of the object, based on a maximum time difference in delay time of the propagation time for the plurality of frequencies in the selected frequency range.