Abnormal sound detection apparatus and detection method

A method for detecting abnormal sound of a test object, comprising the steps of:

• recording as reference data having phase and amplitude in each of multiple frequency bands reference sounds of types not previously recorded as abnormal sounds in the test object similar to the test object;
• acquiring test sound data having phase and amplitude in the multiple frequency bands from test sounds generated by the test object;
• acquiring sound feature data by comparing the test sound data with reference sound data in frequency bands the same as the multiple frequency bands and by changing amplitude of the test sound data based on amplitude of the reference sound data while maintaining phase of the test sound data;
• and
• detecting abnormal sound based on the acquired sound feature data.

An apparatus for detecting abnormal sound of a test object, comprising:

• an electronic control unit constituted of a microcomputer equipped with at least one processor and at least one memory coupled to the processor;
• wherein the processor is configured to:
• record as reference data having phase and amplitude in each of multiple frequency bands reference sounds of types not previously recorded as abnormal sounds in the test object similar to the test object;
• acquire test sound data having phase and amplitude in the multiple frequency bands from test sounds generated by the test object;
• acquire sound feature data by comparing the test sound data with reference sound data in frequency bands the same as the multiple frequency bands and by changing amplitude of the test sound data based on amplitude of the reference sound data while maintaining phase of the test sound data;
• and
• detect abnormal sound based on the acquired sound feature data.