International Archives of Photogrammetry and Remote Sensing. Vol. XXXII, Part 5. Hakodate 1998 
REAL-TIME MEASUREMENT OF ALTITUDE DATA USING THE ACCELEROMETER 
Hidetoshi SUZUKI 
Dep. Civil Eng., Graduate school student, Chiba Institute of Technology 
2-17-1, Tsudanuma, Narashino-shi, Chiba, 275-0016 
E-mail: ins@ce.it-chiba.ac.jp 
JAPAN 
Yasuyuki SHIRAI 
Dep. Precision Eng., Associate Professor, Chiba Institute of Technology 
Atsuro TAKEMOTO 
Dep. Computer Center, Associate Professor, Chiba Institute of Technology 
Toshio KOIZUMI 
Dep. Civil Eng., Professor, Chiba Institute of Technology 
Commission V, Working Group V/2 
KEY WORDS: Inertial navigation system, Accelerometer, Altitude 
ABSTRACT 
In the determination of the position of the platform which collects image sensing information, the information on the height 
direction (altitude) is important. GPS is low in accuracy in determining altitude, though GPS is a powerful means of 
positioning the platform, and its use is difficult in the city region and the mountain region, where the electric wave does not 
reach easily. Moreover, also in the method of computing distance and an angle, respectively, using an accelerometer and 
a gyroscope for the inertial navigation system, and computing a 3-dimensional position, development is advancing(inertial 
survey). However, the accuracy of a gyroscope is low (high accuracy gyroscopes are expensive) and has caused a minus 
factor for utilization. From such a situation, the following two things were developed by this research: Altitude data is 
extracted only using an accelerometer. It is carried in vehicles etc., and altitude data is extracted. When altitude data 
extraction, such as the Mobile matching, becomes important by this, it is considered that it becomes a very effective thing. 
1. APPARATUS USED 
The accelerometer used in this research is Japan Aviation 
Electronics Industry, Ltd. JA-5VC1 accelerometer. The 
power supply of the accelerometer is Japan Aviation 
Electronics Industry, Ltd. PA-1001-11C1 accelero amplifier. 
Moreover, the 24bit A/D conversion board, which changed 
from analog data into digital data and was used in order to 
carry out calculation processing, is Interface company 
98AD24N8S-79 AZI-3108. Measurement equipment 
attaches an accelerometer in a block so that it may 
become a 3 axes rectangular cross as shown in Figuref, 
and it is attached in the stand which prevents vibration. 
2. THE PRINCIPLE OF EXTRACTION OF ALTITUDE 
DATA ONLY USING THE ACCELEROMETER 
  
What is necessary is to catch change of the acceleration of Figure 1 Measurement device 
278 
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