Positioning

The main task of kinematic surveying is the determination of the trajectory

Trajectory Determination

The trajectory consists of three dimensional positions and the related orientation angles and is determined after completion of the survey run in a post-processing procedure. The IMU depicts the movement of the sensor platform in space in dynamic accurate terms. For the estimation of the trajectory robust Kalman filters are used. These filters process all sensor data in a dynamic model with the help of optimal estimation procedures.

A trajectory of constant accuracy without gaps is the basis for succesful georeferencing and orientation of the survey sensor data. The desired accuracy is achieved with an inertial measuring unit as core component in combination with subsequent robust filtering of the measurements. Such a high positioning accuracy can be achieved also in areas where poor or even no GPS positions are available.

Depending on the performance of the used IMU, trajectory accuracies better than 0,5 m in position and height can be obtained for a 3 minute GPS observation gap.