«fiOki
5B-3-1
Mobile Mapping Technologies for Safety Driving Assistance in ITS
Yutaka Shimogaki, Tooru Kitagawa, Yoshiki Yamano, Katunori Takahashi
AAS Research Institute, Asia Air Survey Co., Ltd.
8-10, Tamura-cho, Atsugi-shi, Kanagawa-ken, 243-0016, JAPAN
E-mail: ys.shimogaki@ari.ajiko.co.jp
KEYWORDS: Mobile Mapping System, INS/DGPS integration, ITS, Safety Driving Assistance
ABSTRACT
This paper presents mobile mapping technologies to support effectively Safety Driving Assistance in
the Intelligent Transport Systems (ITS), that acquires the road-related spatial data in advance and
combines them with the equipment mounted on the car while running. The mobile mapping system
(MMS) developed by Asia Air Survey co., ltd. consists of a measurement vehicle and a data processing
unit. The measurement vehicle equipped with.a strapdown Inertial Navigation System (INS), a
differential GPS receiver, an odometer (wheel sensor), two pairs of cameras and an industrial PC
collects position, attitude data and a sequence of terrestrial digital images while driving at regular
speeds. The data processing unit extracts the road infrastructure data from the collected data
through image processing and close-range photogrammetry. A series of field tests have been
conducted to verify the feasibility of the MMS under different conditions. The accuracy of the
Hybrid Inertial Surveying System (HISS) which is the core unit of the measurement vehicle was less
than several meters in 3D position and less than 0.02 degrees in 3D attitude in urban areas where
GPS signals are blocked by tall buildings intermittently. It was verified that the system could
measure road alignment information such as the gradient and the radius of curvature even in the
tunnel because the INS is tightly integrated with the GPS or the odometer. In this paper, after
introducing briefly the trend on ITS in Japan, an overview of the MMS and the Kalman filter model
in the HISS is described. Field tests and the results are also discussed. Finally, the role of MMS in
ITS is emphasized.
1. INTRODUCTION
In the coming new generation, the Japanese
government issued the Comprehensive Plan for
the Promotion of Intelligent Transport System
(ITS) aimed at solving safety, efficiency, and
comfort in connection with road transportation
by using advanced information technology.
Among ITS projects, AHS (Automated Highway
System) is technically the most difficult
program. This project is supported by the
communications between the road and the
vehicle. Namely by providing road-related
information from the road infrastructure to the
telecommunication equipment mounted on the
car, it gives a warning of danger to a driver and
performs automated driving finally. One of
them is the road alignment information.
The road alignment information is available
from the design plan at that time if the road
has not been improved. As a practical matter,
the condition of road changes by the repeated
maintenance work. Accordingly, to get the
information from the map is required. But, in
case of a topographical map with a scale of
1:25000, which is renewed most frequently, the
period to change is 5 years in urban area.
Therefore on the newly constructed or
improved road, it is impossible to get up-to-date
information from the map.
In order to solve this problem, we present the
mobile mapping system (MMS) to acquire the
road alignment information efficiently by
traveling the vehicle with the various sensors.
The Inertial Navigation System (INS), which is
usually used in the aerospace industry, outputs
3D attitudes of the body with respect to local
level coordinate system. When it is equipped
with the land vehicle, it provides the road
gradient from roll angle, the radius of
curvature from heading angle. And also, on
account of high rate, the continuous road
profile can be acquired at intervals of several
ten centimeters. Nevertheless, the INS has the
