Triangulation (surveying)

Triangulation in surveying is when we use three points to figure out the position and distance of an unknown point. Imagine playing a game of "hot and cold" with a friend who has hidden a toy somewhere in the room. You start by standing in one corner of the room and your friend tells you that you're "cold." You take a few steps and your friend says you're "warm." You keep moving around until your friend says you're "hot," and you know you're close to the toy.

This is kind of like triangulation in surveying. Instead of trying to find a toy, surveyors use three known points to help them locate an unknown point. They start by measuring the distance and angles between the three known points, and then use math to figure out the position of the unknown point.

Think about playing a game of "Marco Polo" in a swimming pool. You close your eyes and call out "Marco," and your friends respond "Polo." You know they are somewhere around you, but you're not exactly sure where. So, you move around a little and call out "Marco" again. This time, your friends respond "Polo" from a different direction, and you start to get a sense of where they are. You keep calling out "Marco" and moving around until you finally tag one of your friends.

In surveying, we use instruments like theodolites and total stations to measure the angles and distances between the known points. This is kind of like calling out "Marco" in the pool. By measuring from multiple locations and calculating the angles, we can narrow down the possible locations of the unknown point, just like you were able to narrow down the location of your friend in the pool.

Triangulation can be used for all sorts of surveying projects, from mapping out a piece of land to creating detailed 3D models of a building. With just three points and some careful measurements, surveyors can locate an unknown point with amazing accuracy.