Information processing device

1 . An information processing device comprising a processor configured to:

acquire original data collected and prepared over a predetermined period using a sensor mounted on a vehicle;

extract data to be used to calculate a damage rate of an electric oil pump from the original data; and

execute a search process including:

a first step of calculating, for each of a plurality of feature quantities included in the original data, a relative frequency distribution in the original data,

a second step of setting a plurality of time windows for cutting out data for a part of a period of the original data such that a period obtained by totaling periods of all the time windows is shorter than the predetermined period,

a third step of cutting out data from the original data using the time windows,

a fourth step of calculating, for each of the plurality of feature quantities, a relative frequency distribution in extracted data obtained by combining the data cut out using the time windows, and

a fifth step of calculating an error between the relative frequency distribution in the original data and the relative frequency distribution in the extracted data, wherein

the original data includes data on a rotational speed of the electric oil pump as the plurality of feature quantities; and

the processor is further configured to extract the extracted data whose error is equal to or less than a threshold by executing the search process that repeatedly makes trials to execute the second step to the fifth step while changing settings of the time windows after executing the first step.

2 . The information processing device according to claim 1 , wherein:

the processor is further configured to execute clustering that is machine learning to classify data in sections obtained by dividing the original data for each certain period into a predetermined number of clusters; and

the processor is further configured to set the time windows in the second step such that a difference between a ratio of each cluster in the extracted data and a ratio of each cluster in an entirety of the original data is equal to or less than a threshold.

3 . The information processing device according to claim 1 , wherein the processor is further configured to terminate the search process in a case where one piece of the extracted data whose error is equal to or less than the threshold is successfully extracted, and calculate the damage rate using the extracted data whose error is equal to or less than the threshold.

4 . The information processing device according to claim 1 , wherein:

the plurality of feature quantities further includes data on a temperature of the electric oil pump and a discharge pressure of the electric oil pump; and

the processor is further configured to calculate the damage rate based on at least one of the rotational speed, the discharge pressure of the electric oil pump, and the temperature of the electric oil pump.

5 . The information processing device according to claim 4 , wherein the processor is further configured to calculate the damage rate using the extracted data whose error is equal to or less than the threshold, and make a notification that occurrence of a failure has been predicted in a case where the damage rate is equal to or more than a predetermined value.

6 . The information processing device according to claim 1 , wherein

the plurality of time windows are randomly set for each trial of the search process by randomly determining:

(i) the number of the plurality of time windows;

(ii) a start time of each of the plurality of time windows; and

(iii) an end time of each of the plurality of time windows.

7 . The information processing device according to claim 1 , wherein

the plurality of time windows are set in the second step such that none of the time windows overlap with each other.