OVERVIEW OF ROMDAS
The ROMDAS system is illustrated below:
It is possible to use ROMDAS for:
ROMDAS allows the use of a laptop or notebook IBM compatible PC
to record the following data during a survey:
The first three data items above are recorded through electronic
pulses which are sent to the ROMDAS.
The basic ROMDAS hardwareconsists
The hardware interface connects to a sensor on the roughness meter
and to the distance/speed sensor. During the survey, the interface
monitors both the distance/speed and the roughness meter. Every
0.1 s, the PC interrogates the interface and records the data.
At the end of the survey the data are stored in dBASE-III compatible
The only permanent fixture in the vehicle is the distance/speed
sensor. It is therefore practical to move ROMDAS between vehicles
as long as they are fitted with a distance/speed sensor and harness.
Since ROMDAS uses a portable computer as the data logger, the
computer may also be used for other activities in between surveys.
A response-type roughness meter can be added to measure road roughness.
ROMDAS will convert raw roughness data into calibrated roughnesses
through user-supplied equations. If equations are available for
different speeds, ROMDAS will apply the appropriate equation given
the vehicle speed at the time of the measurement. This removes
the constraint of trying to operate the vehicle at a single survey
speed under all conditions. If the only requirement is a simple
roughness survey, ROMDAS can be run by the driver alone, eliminating
the need for an additional operator.
Travel time and congestion surveys can be conducted using ROMDAS.
These will give the travel time, distances travelled and acceleration
on a second-by-second basis. The system has been specifically
designed to collect data for use in the World Bank's HDM-4 congestion
A 'Transverse Profile Logger' is available which can be used to
measure the pavement transverse profile elevations using ultrasonics
and to establish the rut depth. This instrument stores raw elevation
data which are downloaded to the PC after the survey to calculate
the rut depth under a user-definable straight edge. The transverse
profile distortion is used to estimate potential causes of rutting.
A video recorder can be used to record data on the pavement right-of-way
or the surface. This is connected to the computer video port through
a character overlay device which superimposes the survey chainage
and other basic data on the tape.
LPCD Longitudinal Profile Calibration Device is an instrument used to accurately measure the road profile