Total Station Product

Overview

A total station is the core instrument of land surveying: it measures the precise angle and distance to any point a surveyor sights, and from those it computes the point's position in three dimensions. It merges a theodolite, which reads angles, with an electronic distance meter, which reads range, into one tripod-mounted device.

The surveyor looks through the Sighting Telescope & EDM, aiming its crosshair at a target or reflector. That telescope shares its optical axis with the EDM Laser Emitter and EDM Return Sensor, so wherever it points, the distance meter measures along the same line. The frame rotates on two motorized axes — the Horizontal Angle Drive for azimuth and the Vertical Angle Drive for elevation — each carrying a precise angle encoder. The whole instrument is leveled and centered over a ground mark by the Tribrach & Leveling Base. A Main Processing Board gathers the angle and distance readings and runs the survey math, presenting it on the Display & Keypad Unit; a removable Battery Pack powers a day's work, and the Tripod Mounting Interface ties it to the tripod.

How it works

Angles come from the encoders. As the operator turns the instrument, the glass Horizontal Circle Encoder and Vertical Circle Encoder are read optically to arc-second resolution, giving absolute horizontal and vertical angles to the sighted point; the motorized drives let the station auto-aim and track. A dual-axis tilt compensator corrects those readings for any residual lean left after leveling.

Distance comes from the EDM. The EDM Laser Emitter sends a modulated beam down the telescope line of sight to the target. The returned light lands on the EDM Avalanche Photodiode, and the EDM Phase Timing IC measures the phase shift between the outgoing and returning modulation; that phase, unwrapped across modulation frequencies, gives the range to millimetres. The Main Processing Board combines this slope distance with the two angles to compute the target's northing, easting, and height, then displays and logs the coordinates through the Display & Keypad Unit. Repeated point by point, the survey builds a map of the site referenced to known control.