This document summarizes research conducted to develop a system to improve traffic flows on Dutch highways. The system aims to reduce traffic jams by 30-40% by advising drivers on speeds to maintain through a smartphone app. The app collects GPS and speed data from vehicles and downloads advised speed profiles from a backend server based on real-time traffic conditions. The system architecture involves communication between the app and onboard vehicle units via USB, and between onboard units and roadside units using WiFi for cases where 3G coverage is weak. The backend server performs big data analysis on vehicle data to determine optimal speeds to advise.

1. Abstract — 30 to 40% of traffic jams are happening on
highways in the Netherlands due to sudden braking and
changing speeds [1]. These root causes are preventable if cars
are driven maintaining a stable speed with little brakes. In
order to drive without brakes, knowing in advance about traffic
conditions up ahead will help eliminate braking. In the other
words, you get notifications on decreasing or increasing your
speed by an internet connected application (app). The app
sends your current GPS coordinate [6] and speed to the server
and downloads the data on how the traffic around you behaves.
On that basis, the app continuously gives you speed advice for
your car. The system ensures that you can anticipate faster in
traffic and thus, drive more evenly. This work is a summary of
the research carried on for developing the system to improve
traffic flows on Dutch highways.
Keywords — on-board unit, speed profile, wifi-p, roadside unit,
roadside LAN, GPS, speed
I. INTRODUCTION
VAST of cars are raising up along with the development
of the population of a country. Although the Netherlands
is one of the smallest European country [2], the number of cars
per family is as many as the number of motorbikes per family
in Vietnam. The people often travel to work by car with a long
distance of more than 100 kilometers, which is considered very
normal in the Netherlands [3].
As a result, highway traffic jams are happening during peak
hours. According to the statistics of the research of the Dutch
Ministry of Infrastructure and Environment [1], traffic jams can
be reduced 30 to 40% if the chauffeurs brake less and change
driving lanes not regularly.
To prevent those actions, a research was carried out to develop
a system to give an optimal speed to the chauffeurs driving on
the roads through a smartphone. For achieving this, we first
need to get the current GPS coordinate [6], driving speed,
driving acceleration, previous brake moments, and driving
lanes of the cars. Then, the data will be gathered on the server,
called Back-office, analyzed and calculated in real-time to
provide back to the cars with an advised speed. The system
overview is given in Figure 1, which contains a number of
different communication protocols to support the data exchange
Submitted on: September 07, 2015. This work was carried on by the employees
of Sioux companies in the Netherlands and Vietnam; and was supported by the
Dutch Ministry of Infrastructure and Environment.
between the car and the Back-office server side:
 App to Back-office via 3G
 App to on-board car unit via USB
 On-board car unit to roadside via Wifi-P
Figure 1 - System Architecture
These protocols will be described in the following chapters.
II. APP TO BACK OFFICE VIA 3G
The app retrieves the current coordinate and speed from the
integrated GPS module in the phone. Per predefined interval,
the app will send these information together with the maximum
speed of the car (based on the configuration by the user) toward
the back-office server, which is session-less [9]; while the
session is on the phone.
Figure 2 - A speed profile
A speed profile, which contains minimum and maximum speed
of the driving lane and the advised speed, is returned from the
server. Figure 2 shows an example of providing different speeds
on different positions of the vehicle on the road.
Speed
[km/h]
Position [m]
PDEng. Huy Nguyen, MSc. Robert Hendriksen, BSc. AnhKhoa Nguyen, BSc. Henk Aarts, MSc. Frank Kusters & MSc. Quang Tran
IMPROVING HIGHWAY TRAFFIC FLOWS USING
SMART TECHNOLOGIES
A

2. III. APP TO ON-BOARD CAR UNIT VIA USB
Onboard Unit (OBU) is a Cohda Mk4 device [5]. The Cohda
Mk4 is conceptually similar to the Raspberry Pi [10]. It is a
single-board computer (ARM processor, 512 DDR RAM,
Linux, a CAN bus connector [11], Wifi-P radio [8], GPS
receiver) designed for automotive applications. The device is
mounted inside the car, which is called 'onboard unit' (OBU).
OBU facilitates more data to the phone than just GPS
coordinates and speed; in which we can see the supplied data in
Figure 3:
Figure 3 - Data outputs from Onboard Unit
The OBU not only addresses technical limitations of GPS
coverage and robustness of the integrated GPS module [12]
inside the phone but also provides other useful data such as:
lighting conditions, previous brake moments, accelerations and
driving lanes. OBU provides data to the phone via USB
connection. The app will also send these information toward the
server. This improves the calculations at the server side of not
only returning advised speed, but also advised driving lane and
the statistics of brakes on the current trip.
IV. ONBOARD CAR UNIT TO ROADSIDE VIA WIFI-P
In highway traffic scenarios, when a vehicle meets an
emergency event or behaves abnormally when confronted by
unexpected maneuver or major mechanical failure, it generates
emergency collision warning message and broadcasts it to all
vehicles within its platoon.
There are two main types of communicating message: vehicle
to vehicle (V2V) and vehicle to roadside (V2R). V2R is chosen
to apply on the high way in the Netherlands.
Roadside Unit (RSU) [7] is a computing device located on the
roadside that provides connectivity support to passing vehicles.
They are set up every certain distance on the high road in
Holland. They help all the vehicles in their range communicate
with each other via Wifi-P [8]. The mechanism is illustrated in
Figure 4 below:
Figure 4 - Roadside LAN communication
With this add-on communication, in case there is a problem
with 3G or GPRS coverage on the roads or GPS technical issue,
this communication can support to transfer the data to the
server. However, implementing roadside protocol on the roads
involves a lot of costs and effort in installations, this is therefore
only applied at high traffic roads with weak 3G signal.
V. BACK-OFFICE SERVER FOR BIG DATA
At the Back-office server, there are huge volume of data
received from different sources: the Apps and roadsides. A
multi-distributed system [13] was developed, which is called
Big Data Analyzer, contains a lot of mathematic models,
routing algorithms and real-time analytic models. Formally, it
is known as a high quality decision maker running 24/7 with a
very high reliable up-time to deliver optimal advised speeds and
driving lanes on the roads for the chauffeurs based on a lot of
real case studies on traffic jams in the Netherlands like Figure
5.
Figure 5 - Case studies on traffic jams
VI. CONCLUSIONS
Around the world, we are working on ways to make traffic
faster, safer, more comfortable and sustainable. The
Netherlands is a leader in the development of traffic
communication techniques, in which vehicles communicate
with each other and work together to reduce congestion,
increase road capacity, improve comfort for the driver and
increase the safety. The goal of the project scope is to improve
traffic flow on the highways in the Netherlands. But the
ambitions go further: with the success of the project, the

3. partners of the project want to expand the services of the
projects to support other European countries.
VII. FUTURE WORKS
The results achieved so far have been promising after finishing
the testing phase in the Netherlands for a half year. However, a
number of components in the system still can be improved. The
app was first developed for Android and it can be ported on
other platforms such as: iOS and Windows phone so it brings
more flexible for choices for the users. The advantage of the
current app development facilitates the porting process as an
easy because Xamarin [4] technology was chosen. The Big
Data Analyzer was developed with a lot of effort and attention
to calculate the data in real-time situation. Based on the testing
results, there were still unexpected cases happening. It requires
more fine-tuning and optimizing the algorithms to improve the
robustness of the system.
REFERENCES
[1] Spookfiles A58, Dutch Ministry of Infrastructure and
Environment
[2] Wikipedia, List of European countries by area. Available:
https://en.wikipedia.org/wiki/List_of_European_countries_by
_area
[3] M. Dijst, Academia Education, International comparison of
long-distance travel: United Kingdom and the Netherlands
[4] Xamarin, Building Cross Platform Applications. Available:
http://www.xamarin.com
[5] Cohda Wireless MK4 specification. Available:
http://cohdawireless.com/Portals/0/PDFs/CohdaWirelessMKX
SDK.pdf
[6] Garmin, What is GPS and how does it work? Available:
http://www8.garmin.com/aboutGPS/
[7] IGI Global, What is Roadside Unit? Available:
http://www.igi-global.com/dictionary/roadside-unit-rsu/37000
[8] EEE 1609, Family of Standards for Wireless Access in
Vehicular Environments (WAVE), U.S. Department of
Transportation, April 13, 2013.
[9] R. Zuasti, WebCodeGeeks, Developing Stateless (session-
less) web apps, October 24, 2014
[10] Raspberry Pi, A tiny computer. Available:
https://www.raspberrypi.org/
[11] CAN Bus. Available:
https://en.wikipedia.org/wiki/CAN_bus
[12] J. Artman, Small Business, Advantages and Disadvantages
of Cellphone Tracking
[13] M. Wooldridge, An Introduction to Multi-Agent Systems.
ISBN 0-471-49691-X, 2012