In the disclosure, a failure of a device performing work while moving is more reliably detected while the data amount of failure diagnosis data is reduced. The disclosure includes a frequency analyzing part which performs a frequency analysis on acquired data from an acceleration sensor; a maximum frequency detecting part which detects a maximum frequency from a result of the frequency analysis; and a failure diagnosis data generating part which sets a frequency twice or more of the maximum frequency as a sampling frequency, samples the acquired data from the acceleration sensor, and generates the failure diagnosis data.