VARIOUS TYPES OF INSTRUMENTS USED IN SURVEYING

1. Cosmolabe.

The cosmolabe was an ancient astronomical instrument resembling

the astrolabe, formerly used for measuring the angles between heavenly bodies. It is

also called pantacosm.

2. Dioptra.

The dioptra was a sighting tube or, alternatively, a rod with a sight at both

ends, attached to a stand. If fitted with protractors, it could be used to measure angles.

3. Theodolite.

A theodolite is a precision instrument for measuring angles in the horizontal

and vertical planes. Theodolites are used mainly for surveying applications, and have

been adapted for specialized purposes in fields like meteorology and rocket launch

technology.

4. Tacheometer.

A tachymeter or tacheometer is a type of theodolite used for rapid

measurements and determines, electronically or electro-optically, the distance to

target. The principles of action are similar to those of rangefinders.

5. Subtense bar.

This is a rigid rod, usually of a material insensitive to change in temperature

such as invar, of fixed length (typically two metres). The subtense bar is mounted on

a tripod over the station to which the distance is desired.

6. Graphometer.

The graphometer, semicircle or semicircumferentor is a surveying

instrument used for angle measurements.

7. Total station.

A total station or TST (total station theodolite) is an electronic/optical

instrument used in modern surveying and building construction. The total station is

an electronic theodolite (transit) integrated with an electronic distance meter (EDM)

to read slope distances from the instrument to a particular point.

8. Alidade.

An alidade or a turning board is a device that allows one to sight a distant

object and use the line of sight to perform a task.

9. Plane table.

A plane table is a device used in surveying and related disciplines to provide a

solid and level surface on which to make field drawings, charts and maps. The early

use of the name plain table reflected its simplicity and plainness rather than its

flatness.

10. Dumpy level.

A dumpy level, builder's auto level, leveling instrument, or automatic level is

an optical instrument used to establish or verify points in the same horizontal plane.

It is used in surveying and building with a vertical staff to measure height differences

and to transfer, measure and set heights.

11. Tape.

It is a common measuring tool.

12. Prismatic compass.

Prismatic compass is a navigation and surveying instrument which is

extensively used for determining course, waypoints (an endpoint of the leg of a

course) and direction, and for calculating bearings of survey lines and included angles

between them.