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Clarke, Tim 
  
  
Figure 7. Drilling trials 
9. VERIFICATION OF PERFORMANCE 
The performance of the system is in the process of being tested. There are four aspects to this work: (a) Target error 
estimation using simulation to predict the error map for the system which varies considerably throughout the measurement 
volume. (b) Error propagation from targets through to the component tolerances. (c) Direct testing using known rotations 
and translations to compare measured to reference. (d) Direct testing using a length artifact (figure 8 & 9). The work being 
conducted for this last section is part of a wider program of research to develop a consistent method for photogrammetric 
systems and Laser Trackers based upon the ISO 10360-2 standard. 
  
  
  
    
  
  
  
  
  
Figure 8. Three length artifact measurement location Figure 9. Four length artifact measurement locations 
aligned with the x axis aligned with the y axis. 
10. FUTURE WORK 
The work described in this paper is now reaching the stage where it will be rigorously tested and analysed. By pulling 
together all elements from image processing to 6DOF calculations it is expected that verifiable performance will be 
obtained. Whether this system capability together with the advantages and disadvantages of the methodology are 
appropriate for it to be applied to the application for which it is has been developed is not ultimately important. It is 
expected, however, that by being able to demonstrate capability rigorously in one instance it will be possible to apply the 
techniques in other applications. 
  
International Archives of Photogrammetry and Remote Sensing. Vol. XXXIII, Part B5. Amsterdam 2000. 141