Image-based Target Detection and Tracking Using Image-assisted Robotic Total Stations
Volker SCHWIEGER, Otto LERKE et al
University of Stuttgart Volker Schwieger 84040 Institute of Engineering Geodesy (IIGS)
Robotic total stations are modern geodetic multi-sensor systems measuring horizontal and vertical angles as well as distances using time-of-flight methods, thus delivering 3Dcoordinates for static as well as moving objects. Automatic target detection (by rough and fine pointing techniques) and tracking are standard techniques if the objects are signalized with
reflectors and the total station is motorized. Nowadays these instruments are additionally
equipped with one or two cameras to generate images mainly for documentation purposes.
This paves the way to detect and track objects that are not signalized by reflectors. Photogrammetric
techniques such as SURF (Speeded-up Robust Feature) or SIFT (Scale Invariant
Feature Transform) are applied for the detection of special, recognizable object features in the images. The pixel coordinates of these features result in vertical and horizontal angles if the
parallaxes between the camera optical center and the total station origin are known or
calibrated. If the features are extracted in a sequence of images the movement of any object can be tracked automatically. For the position determination reflectorless distance measurement from the total station to the object is required additionally. Until now this was realized only for static objects. In this contribution an example of a kinematic application is also shown. The quality of these tracking procedures may be verified by an instrument of higher accuracy. This has been done using a laser tracker.
Event: FIG WW 2019 Hanoi
Only personal, non-commercial use of this document is allowed.