US 12,422,281 B2
Estimation device, apparatus including estimation device, estimation method, and computer-readable medium
Hidekazu Tsukiji, Tokyo (JP)
Assigned to Asahi Kasei Microdevices Corporation, Tokyo (JP)
Filed by Asahi Kasei Microdevices Corporation, Tokyo (JP)
Filed on May 30, 2023, as Appl. No. 18/325,126.
Claims priority of application No. 2022-105375 (JP), filed on Jun. 30, 2022.
Prior Publication US 2024/0006965 A1, Jan. 4, 2024
Int. Cl. G01D 5/14 (2006.01); G09F 9/30 (2006.01); H02K 11/215 (2016.01)
CPC G01D 5/145 (2013.01) [G09F 9/301 (2013.01); H02K 11/215 (2016.01)] 21 Claims
OG exemplary drawing
 
1. An estimation device in an apparatus including a first portion, a second portion, a drive mechanism configured to move the second portion with respect to the first portion along a predetermined direction within a predetermined range of movement, a plurality of magnetic sensors provided in one of the first portion and the second portion along the predetermined direction, and a magnet unit that is provided in the other of the first portion and the second portion and that is configured to provide a magnetic field which is measured by the plurality of magnetic sensors,
the estimation device being configured to estimate a position of the second portion with respect to the first portion, and comprising:
an estimation unit configured to estimate the position of the second portion with respect to the first portion at a first point in time, based on a measured value at the first point in time measured by each of the plurality of magnetic sensors, and reference information indicating a combination of a measured value of each of the plurality of magnetic sensors in accordance with the position of the second portion with respect to the first portion in the predetermined range of movement;
a collection unit configured to collect a measured value which is measured by each of the plurality of magnetic sensors, in a first period during which the drive mechanism is driven to move the second portion with respect to the first portion along the predetermined direction over the predetermined range of movement in a predetermined operation pattern; and
an update unit configured to generate new reference information based on a measured value in accordance with a time measured in the first period by each of the plurality of magnetic sensors, and update the reference information by the new reference information, wherein
the update unit is configured to correct the position of the second portion with respect to the first portion or the measured value of a predetermined first magnetic sensor, which is indicated by the new reference information, by comparing a predetermined first partial waveform in a first waveform for the first magnetic sensor among the plurality of magnetic sensors, the first waveform indicating a change of the measured value in accordance with the position of the second portion with respect to the first portion, which is indicated by the new reference information, with a predetermined second partial waveform in a second waveform for a predetermined second magnetic sensor among the plurality of magnetic sensors, the second waveform indicating the change of the measured value in accordance with the position of the second portion with respect to the first portion, which is indicated by the new reference information.