SRV-27

Forward coordinate

E = E0 + ΔE, N = N0 + ΔN. A new station from a known one.

Reading speed

CoordinatesGrid coordinates

Governing equation

E=E_0+\Delta E,\quad N=N_0+\Delta N

where

E_0: Start easting (m)
N_0: Start northing (m)
\Delta E: Departure (m)
\Delta N: Latitude (m)
E: Easting (m)
N: Northing (m)

Lecture brief

Historical brief

From chain and theodolite through Bowditch’s compass-rule (1802) to GPS PDOP, surveying is the propagation of small errors across a network. These sheets close traverses, reduce stadia and state map scale. This sheet (SRV-27 — Forward coordinate) is the form associated with Grid coordinates. Working symbols: $E_0$ , $N_0$ , $\Delta E$ , $\Delta N$ $\rightarrow$ $E$ , $N$ . The traverse update. Close the loop and Bowditch-adjust ΔE, ΔN before storing the station.

Purpose

Purpose: compute

E

N

from

E_0

N_0

\Delta E

\Delta N

in Surveying via

E=E_0+\Delta E,\quad N=N_0+\Delta N

E = E0 + ΔE, N = N0 + ΔN. A new station from a known one. Use it when a real surveying question must be answered in SI before a code check.

Live realistic example

In symbols

Live case. Given

E_0 = 50000.000\,\mathrm{m}

N_0 = 120000.000\,\mathrm{m}

\Delta E = 85.400\,\mathrm{m}

\Delta N = -32.100\,\mathrm{m}

, the governing relation

E=E_0+\Delta E,\quad N=N_0+\Delta N

yields

E = 50085.400\,\mathrm{m}

N = 119967.900\,\mathrm{m}

. A known point, a vector, a new station. Move a slider: the numbers are this situation, not a canned story.

Calculator

Inputs

Start easting E_050000 mStart northing N_0120000 mDeparture \Delta E85.4 mLatitude \Delta N-32.1 m

Outputs

Easting E50085.400 m
Northing N119967.900 m

Reading speed

Watch on YouTube

Free library

Full library

Free PDF / open book

YouTube channels

00:0 / 00:08

Narration of this film

A known point, a vector, a new station.

The traverse update. Close the loop and Bowditch-adjust ΔE, ΔN before storing the station.

Reading speed

Watch on YouTube