EEE ee“ 
2.4. Traffic Accident and Photogrammetry 
Unless specially demanded otherwise, all 
stereo-compilation: is carried out at a 
scale. of .1:200 with: contouring being 
optional. The extent of police work in the 
country can be imagined from the 1986 
statistics. That.year,.of the 579,190 
accidents, around 50 %(288,213 accidents) 
occurred in the areas equipped with ster- 
eo-camera. The participation of police 
wars with stereo-camera were 169,931 in 
number and a total of 52,647 photo-pairs 
were taken of which actually 20,487 scenes 
were mapped with numbering 38.9% off total 
pairs. These plotted maps are used for the 
use of various courts. There were invaria- 
bly submitted with field measurement of 
various types as deemed necessary for 
disposal of cases. The photogrammetric 
operations of the police in Japan, al- 
though initially discouraged by the legal 
profession, now seem to enjoy considerable 
support from the judiciary department. 
Japan is divided into 47 administrative 
divisions (like states in the U.S.)known 
prefectures. The total police force in the 
country is around 220,000 of whom approxi- 
mately 2,600 are engaged in photogrammet- 
ric work. Of these, about 200 are photo- 
grammetrie operators, mostly eivilians, 
with roughly 30 percent being uniformed 
police officers. 
2.5 Analysis Results of Mapping 
Normally mapping at accident sites at a 
Scale of 1:200 is standard, differ on a 
case by case basis regarding special jobs, 
especially for the mapping case for air- 
plane explosion, train collision sites and 
explosion sites of chemical factories. The 
mapping accuracy is closely related to the 
photo-taking conditions, operating instru- 
ments and operator's skill. In general, 
mapping accuracy is normally +0.2mm on the 
map within the range of 4 to 20 times of 
base length, that means, +4cm in actual 
length at a scale of 1:200. In case of an 
analytical measuring system, accuracy of 
reading on the: plate if +5um for PAMS 
and +lum for PHOCAS. Accuracy is related 
to: the control point position and: their 
arrangement, especially mark itself is a 
big cause of errors. The police Agency 
made up the marks so that they can be seen 
and measured easily. 
2.6 Conclusion and Remarks 
Ten years have passed already since the 
national project has started. There are 
big differences in use depending on the 
prefecture, some are very active and a few 
prefectures are dull because of knowledge 
in photogrammetry and training and also 
camera and plotting machines are very 
expensive and take time to master. The 
regular operations take around 0.1% of the 
total police budget every year in the 
country. Some cost samples are ¥3.0 mil- 
lion for one stereometric camera with 
accessories; ¥4.0 million for one special 
vehicles; and ¥6,000 for 12 glass plates. 
    
   
   
    
    
    
   
     
     
    
   
    
   
   
    
   
    
   
   
    
   
     
   
   
    
     
    
   
  
  
  
   
   
  
   
     
   
  
  
  
   
    
   
    
    
   
  
  
   
   
  
  
  
   
   
   
   
   
    
The experience that the police in Japan 
have had, resulted in the raising of the 
scientific manager power among the police. 
But in actual works, there are several 
problems proposed by each prefecture as 
shown in followings: 
(1) Deterioration of the camera and 
plotting machines. 
(2) Lack of good technicians for photo- 
taking and plotting 
(3) Price increase for necessary materi- 
als 
(4) Photo-taking trouble at snow and 
raining areas 
(5) Careless usage of cameras on the road 
by policeman 
(6) Traffic troubles in the down-town 
area during photographing because of a 
shortage of policemen 
froThere will be more multiplied applying 
way increased to solve the trouble related 
to the police. The PAMS and PHOCAS is 
ready on the market and more than 10 
instruments are used for police work in 
JAPAN. 
ACKNOWLEDGEMENT 
FOR the paper of measurement of Hiroshima 
cenotaph,Chap.1, the author would like to 
express the heartiest thank for the valu- 
able support by Mr. Fujioka,Oobayashi gumi 
DY Associate Prof. Suga and his 
student,Hiroshima Institute of Technology 
and the on-site guidance and advice given 
by Dr. Tanaka,Remote Sensing Technology 
Center. 
For the paper of Closé-Range Photogramm- 
etry for traffic accident sites, the 
author are very indebted to Mr. Shiota and 
Mr.Akiba, Traffic Bureau,the National 
Police Agency and would like to thank to 
Mr. Saito, Asahi Optical Co. The author 
would like to acknowledge he valuable 
support and advice rendered by Prof. 
Ghosh,Laval University,Canada. 
  
Photo. 2. PAMS (Photogrammetric Analytical Measurement System) 
  
é $ 
b *a 
Photo. 3. Specially designed Stereometric Camera 
(Asahi Pentax PAMS 645)