odometer vs tachograph

odometer

noun
  • An instrument, usually embedded within the speedometer of a vehicle, that measures the distance the vehicle has traveled since production. 

  • A wheel used by surveyors, which registers distance traveled. 

tachograph

noun
  • A device that records the distance and time traveled by a vehicle (especially a truck or coach), used to check the drivers' working time. 

How often have the words odometer and tachograph occurred in a corpus of books? (source: Google Ngram Viewer )