Three-point Problem

The position of latest plane table station on the map could be correctly located with the help of three well described points on ground whose positions are already plotted on map. Like a procedure is known as three-point problem. It is obvious in which locating the position of table through this procedure is more accurate. Therefore, it is more include and complex.

Now let there are three ground stations A, B and C those positions are marked as a, b and c on the plan map and let those stations are visible from new table station O. It is needed to plot the position of O on map as o. This can be achieved through any of the following methods:

(a)       Mechanical

(b)       Graphical

(c)       Trial and Error