| 摘要 |
PROBLEM TO BE SOLVED: To provide knocking estimating technique robust against noise.SOLUTION: A knocking estimating device 1 includes a vibration sensor 5 (vibration detecting means) for detecting vibration of a cylinder block 4 and generating a vibration signal S, a sampling part 10 (sampling means) for sampling the vibration signal S based on engine speed, a frequency characteristic calculating part 11 (frequency characteristic calculating means) for calculating a frequency characteristic of the vibration signal S by Fourier-transforming the sampled vibration signal S, a period characteristic calculating part 12 (period characteristic calculating means) for calculating a period characteristic of the frequency characteristic by Fourier-transforming the frequency characteristic calculated by the frequency characteristic calculating part 11, and a knocking occurrence state estimating part 13 (knocking occurrence state estimating means) for estimating an occurrence state of knocking based on the period characteristic calculated by the period characteristic calculating part 12. |
