288 
3. INDUSTRIAL USE AND FIELDS OF APPLICATION 
3.1 Automotive industry: Digitization of design models 
The automotive industry. offers optimum conditions for the use of the InduSURF system, as the measuring tasks 
frequently involve the digitization of design models or of complete 1:1 car bodies. In conventional measuring techniques, 
the difficulty of precise and efficient measurement increases with the size of the models. Compared with 
photogrammetry, the workload and costs involved are disproportionately high. The German VOLKSWAGEN group has 
been successfully using the Zeiss InduSURF system for several years now. This system which is based on analog UMK 
10/1318 images requires an evaluation period of approx. 10 to 15 working days for the complete digitization of half a 1:1 
model. The digital InduSURF system only needs an evaluation period of approx. 5 working days for the same model 
while digitizing roughly 10 times more points, and thus sets new standards in this field. A major advantage lies in the 
fact that the models only need to be available for the time required for preparation and image recording and can then be 
returned to the machining process after a maximum of 1 working day. This is achieved first and foremost by the 
systematic use of the large-format UMK 10/1318 as a macro-scanning camera whose - now digitized - image field may 
cover a size of up to 15414 x 11040 pixels. For smaller objects or details, digital images are recorded and processed 
with the JenScan micro-scanning camera. 
  
InduSURF Digital - Digitization of car design models 
  
Task: Digitization of the following models with a maximum, but economically justifiable point density 
Q Grand Cherokee jeep (1:1 series model), 
O future prototype (car body, 1:1 clay model), 
Q interior console (handbrake, 1:1 clay model). 
  
  
Parameters 
1:1 Clay Model of Car Body 
1:1 Clay Model of Console 
  
Sensor used 
Number of images 
Data quantity 
Defined point on the object 
Recording time 
Measurement and orientation 
Point accuracy 
UMK-SCAN, ck = 100 mm 
46 images (23 models) 
3.5 GBytes 
58 retro-targets 
6 hours 
6 hours 
Sx/z = + 0.15 mm, Sy = + 0.16 mm 
JenScan, ck = 14 mm 
38 images (19 models) 
0.5 GByte 
46 retro-targets 
4 hours 
3 hours 
Sx/z = + 0.16 mm, Sy = + 0.18 mm 
  
InduSURF SGI computer 
Point number in DEM 
Computation time 
Mean elevation error 
  
  
Indigo2, 150MHz, 128MB RAM 
480 000 points (5 mm grid) 
approx. 20 hours 
Sy = + 0.20 mm 
  
Indigo2, 150MHz, 128MB RAM 
350 000 points (1 mm grid) 
approx. 24 hours 
Sy 2 x 0.18 mm 
  
  
Table 2: Results of clay model digitization 
  
Fig. 4: 3D point cluster of jeep fender 
IASPRS, Vol. 30, Part 5W1, ISPRS Intercommission Workshop "From Pixels to Sequences", Zurich, March 22-24 1995