What is the difference between a tacheometer and a theodolite?

Answer 1

A tacheometer is a type of theodolite used for rapid measurements. It determines the distance to the target electronically or electro-optically. Tacheometry is a system of rapid surveying that does not use chain or tape. There are times when measuring with a theodolite and measuring tape can be dangerous or impossible.

A theodolite is an older surveying tool. Those were just precision optical devices used to compute angles between known fixed points, and they required using trigonometry to get the final values. However, there are modern versions of theodolites called Total Stations that are more convenient to use than even a tacheometer. These will cost you about $50,000 a piece or so.

Please note that the question asks about a tacheometer (or tachymeter) which is a surveying tool, not a tachometer which measures engine speed.

Answer 2

Tacheometer is a somewhat obsolescent term for a type of distance meter or range finder, somewhat similar to a theodolite as it is precisely leveled and it used from a tripod. Tachometer ( to measure speed) is the device that indicates the shaft speed of a motor vehicle engine, and is always calibrated in Revolutions per minute- or RPM. As I mis-thought in the drummer boy song- Then he nudged her ( sound effects) followed by the R.P.M. kept time! ( sounds like a song like the Hot Rod Lincoln!