3 rd International Conference on Machine Control & Guidance Proceedings, 202-210, Stuttgart, Germany, March 27-29, 2012 Modular Imaging Total Stations – Sensor Fusion for high precision alignment Stefan Hauth, Martin Schlüter, Florian Thiery i3mainz - Institute for Spatial Information and Surveying Technology, Fachhochschule Mainz - University of Applied Sciences, Mainz Abstract Initialized in 2009, the Institute for Spatial Information and Surveying Technology (i3mainz), Mainz University of Applied Sciences, forces research towards modular concepts for imaging total stations. On the one hand, this research is driven by the successful setup of high precision imaging motor theodolites in the near past, on the other hand it is pushed by the actual introduction of integrated imaging total stations to the positioning market by the manufacturers Leica Geosystems, Sokkia, Pentax, Topcon and Trimble. Modular concepts for imaging total stations are manufacturer independent to a large extent and consist of a particular combination of accessory hardware, software and algorithmic procedures. The hardware part consists mainly of an interchangeable eyepiece adapter offering opportunities for digital imaging. An easy assembly and disassembly in the field is possible allowing the user to switch between the classical and the imaging use of a robotic total station. The software part primarily has to ensure hardware control, but several level of algorithmic support might be added and have to be distinguished. Algorithmic procedures allow reaching several levels of calibration concerning the geometry of the external digital camera and the total station. Here the resulting resolution capacity of our sensor fusion and also the accuracy of the system are presented based on examples. We deliver insight in our recent developments and quality characteristics. The sensor fusion between camera and polar measuring system allows detecting and measuring different types of targets with high precision. MoDiTa is used to calibrate inclination sensors and to control the long-term stability of laser and tripods. Keywords Imaging total station, sensor fusion, image processing 1 INTRODUCTION The combination of polar measurement systems using modern digital industrial cameras keeps growing in the area of measurement technology. Some commercial producers of polar measurement systems like Pentax, Trimble, Topcon or Leica Geosystems now offer this combination as an integrated system, cf. HAUTH/SCHLÜTER (2010). In addition to the aforementioned manufacturers, research institutes also develop solutions and applications of modular imaging total stations, which carry a camera in front of the eyepiece. A prototype of a theodolite combined with a digital camera, developed at the i3mainz, shows the successful use of technical precision measuring SCHLÜTER ET AL. (2009). The MoDiTa – Modulares DigitalkameraTachymeter (modular imaging total station) of i3mainz is a consistent continuation of the previously mentioned theodolite combined with a digital camera on a modular base, which is examined in the BMBF-funded (Federal Ministry of Education and Research) research project "Modulare DigitalkameraTachymeter". WASMEIER 2009 from the University of Technology München presents the prototype IATS2 based on total station Leica Geosystems TCRA1201. IATS2 replaces the reticule with a CMOS-chip and removes the eyepiece. The camera is fix integrated in the total station and complicates an adaptation for different applications or the changing back to a “classic” total station. An advantage is the good compactness of the system. BÜRKI 2010 from the Institute of Geodesy and Photogrammetry at the Swiss Federal Institute of Technology in Zürich shows with the system DAEDALUS a combination between digital camera and total station, too. This replaces the eyepiece with a CCD-chip and requires no additional optical