10.6.4 Total Station
Total station consists of a device to measure horizontal and vertical angles, along with capability to measure distance with help of Electromagnetic Distance Measurement (EDM) system. This allows the surveyor to measure 3D coordinates of points remotely, typically targeted by the placement of reflective prisms. It also permits recording of the data in a digital format to be later downloaded or transmitted to a central processing site. The latest total station instruments are equipped with servo-motors and automatic target recognition algorithms that reduce the need for personnel to physically record the observations. Additionally, due to the introduction of reflectorless instruments, survey prisms are no longer required at the slope surface. One advantage of using total stations to monitor surface deformation is that the measurements can provide 3D position solutions of the point of interest.