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HIGH RESOLUTION DATA ACQUISITON TO OBSERVE MOVING OBJECTS
Jürgen Dold, Leica AG, CH - 5035 Unterentfelden, Switzerland
Jürgen Peipe, Universität der Bundeswehr München, D - 85577 Neubiberg
Commission V, Working Group 3
KEY WORDS: Dynamic, Inspection, Monitoring, Digital Industrial Photogrammetry, Digital Motography
ABSTRACT
Due to their on-line and real-time capabilities digital photogrammetric close range systems are well suited to the task
of object tracking and motion analysis. In this paper, test measurements of a moving object using high resolution
digital cameras (2K x 2K, 3K x 2K pixel) are described. On-line and off-line data processing is performed by the
digital photogrammetric system V-STARS. The results of the photogrammetric technique and a 3-D laser tracker are
compared.
KURZFASSUNG
Digitale Systeme der Nahbereichsphotogrammetrie sind wegen ihrer Möglichkeiten zur on-line und real-time
Messung gut geeignet für die Objektverfolgung und Bewegungsanalyse. In diesem Bericht werden Testmessungen
an einem bewegten Objekt mit Hilfe hochauflösender digitaler Kameras (2K x 2K bzw. 3K x 2K Bildelemente)
beschrieben. Die on-line bzw. off-line Auswertung der Bilddaten wird im digitalen photogrammetrischen System
V-STARS durchgeführt. Die Ergebnisse des photogrammetrischen Verfahrens werden mit denen eines Laser-
Trackers verglichen.
1. INTRODUCTION applied to increase the achievable accuracy of object
motion reconstruction. On-line 3-D point determination
3-D object tracking and motion estimation have been is carried out with Kodak Megaplus 4.2 cameras and
effectively applied in areas such as biomechanics, the Leica V-STARS/M2 digital photogrammetric
sports sciences, material testing, medicine, hydro- measurement system. Kodak DCS 460 cameras are
mechanics, robotics, monitoring and quality control in used in an off-line approach. The object is signalized
industry. A variety of measurement equipment and with active or passive markers (LED's or retroreflective
methods have been used, including servo controlled targets, respectively) and recorded by the cameras with
theodolites, interferometry, photogrammetry etc.. open shutter. During object motion, light points or light
traces are generated in single images.
Digital photogrammetric close range systems allow for
on-line or even real-time data acquisition and pro- It is aimed to present different high resolution photo-
cessing. Therefore, a great number of motion grammetric methods suitable to different motion
measurement tasks can be solved, e.g. particle tracking analysis tasks and to give results of a performance test
for the evaluation of fluid motion, robot guidance and using the same moving object. In addition, the photo-
monitoring, determination of human movement, control grammetric systems are compared with the outcome of
of systems for autonomous driving, observation of a Leica SMART 310 3-D Laser Tracker.
moving objects in an assembly line (see e.g. the
sections "Motion estimation and tracking" and "Image 2. TEST SETUP
sequence analysis" in Baltsavias (1995); Gruen, 1992;
Maas, 1994). Standard CCD cameras providing 25 or A system for the measurement of kinematic processes
30 frames per second and up to 750 x 580 pixels are should be able to record more or less continuously
mainly used to acquire the digital image data. Higher information from which 3-D coordinates can be derived.
video rate but lower resolution is obtainable with high Depending on the task, it can be neccessary to track
speed video cameras. only a single point but also multiple points. Besides, the
measurement systems described in the following
In this paper, motion recording performed with high ^ sections provide very different data acquisition rates.
resolution digital data acquisition devices is discussed. The laser tracker is able to record 1000 single points
Cameras providing a 2K x 2K or 3K x 2K sensor are per second (point after point), whilst the digital photo-
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International Archives of Photogrammetry and Remote Sensing. Vol. XXXI, Part B5. Vienna 1996
