A Dynamic Bus Guide Based on
Real-Time Bus Locations
A Demonstration Plan

Ikuko Shigihara, Akiko Arai, Osamu Saitou, Yuji Kuwahara and Masaru Kamada
Graduate School of Science and Engineering
Ibaraki UniversityHitachi, Japan{13nd302s, 13nd301y}@hcs.ibaraki.ac.jp, {o-saitou, kuwahara, m.kamada}@mx.ibaraki.ac.jp

Abstract—Motorization liberated our life from timetables ofthe public transportation. As the cars became more affordable,
the buses became more unpopular and less frequent. Too manycars flooding on the streets caused heavy traffic jam, which madethe buses even more unpopular for their arrival got almostunpredictable. Now the bus transportation in small cities has
only sparse and unreliable timetables. That forms a negative
spiral for our community to keep losing efficiency in both fueland time. Even though we cannot operate buses punctually to a
fixed timetable, we can still operate them precisely relative to a
dynamic timetable that is based on the location of buses actuallyrunning in real time. This dynamic timetable will be a first step
toward regaining popularity for the buses and breaking thenegative spiral. This paper presents our project of implementing
a dynamic timetable of buses in a small city in Japan. Each bus
carries an Android tablet with GPS and 3G wireless connections.
The tablets transmit the bus positions to a server. The servershows the real-time bus locations on a map and also predicted
future locations. Passengers can check this dynamic timetable toplan their travel.
Keywords—Bus location; web service; GPSI.

INTRODUCTION

Motorization liberated our life from timetables of the public
transportation. As the cars became more affordable, the buses
became more unpopular and less frequent. Too many cars
flooding on the streets caused heavy traffic jam, which madethe buses even more unpopular for their arrival got almost
unpredictable. Now the bus transportation in small cities has
only sparse and unreliable timetables. That forms a negative
spiral for our community to keep losing efficiency in both fueland time.
Even though we cannot operate buses punctually to a fixed
timetable, we can still operate them precisely relative to a
dynamic timetable that is based on the location of buses
actually running in real time. This dynamic timetable will be afirst step toward regaining popularity for the buses andbreaking the negative spiral.
This paper presents our project of implementing a dynamic
timetable of community bus system in a small city in Japan.
Each bus carries an Android tablet with GPS and 3G wirelessconnections. The tablets transmit the bus positions to a server.
The server shows the real-time bus locations on a map and also
predicted future locations. Passengers can check this dynamic
timetable to plan their travel.
II.

EXISTING INFORMATION SYSTEMS FOR PUBLIC
TRANSPORTATION NETWORKS

A. Train route finder
Web-based services [1-3] to find train routes have been
popularly used for planning travel by trains from a station toanother. They suggest routes optimized for traveling time, fare,and number of transfer connections. The routes and travel plans
with the time for transfers taken into account are sought on thebasis of train timetables of the day. The resulting travel plans
are very useful under the assumption that all the concerned
trains are punctually operated.
Those services have been expanding their coverage oftransportations to include major bus routes. To buses, however,the punctuality assumption is hardly applicable.
B. Bus location service
A traditional information service for bus arrival anddeparture is based on detection of buses passing by at the busstops. An electronic signboard is built at each stop that has aradio receiver to communicate with a transmitter mounted on
the bus by short-range radio communications. At stops aheadof the bus, it is displayed how much the forthcoming bus isrunning behind the schedule. This system has been in service
since 1978 in Tokyo.
Recent services utilize the GPS measurement of bus
locations and the mobile digital communications to collect thelocation data to the central server. It has become possible tomonitor long-distance buses and airport shuttle buses that have
only sparse stops.
C. Dynamic bus timetable service
Tottori Bus Net [4] developed by Tottori university is aleading project in bus information service. It started as a bus
location service to monitor visually buses running currently.

Now the real-time bus locations are being used to calculate theplans for traveling by a bus after another toward the destination.
D. Dynamic scheduling of on-demand busesOn-demand bus system is a solution for very rural areas
where regular operation of buses is financially unsustainable.
A very intelligent system has been developed for re-schedulingthe route of running bus as new demands are coming in [5].
III.

DYMAMIC BUS GUIDE APPLIED TO COMMUNITY BUS

A. Problems with community bus service
In small cities not very urban or very rural, there is adifferent category of bus service called community bus. Thecommunity bus service is operated regularly but is different
from ordinary bus network in its mission. It aims at providinginexpensive and convenient transportation for shopping andmedical care to mainly elderly people within a limited area. It
is optimized not for traveling time but for covering the resident
area densely in space and frequently in time.

Fig. 1. Examples of community bus routes (yellow, pink, and bluecircuits) along with two train lines (green and red).

Figure 1 shows three examples of community bus circuitsin the target field, the city of Hitachi-Naka, along with twotrain lines. The green and red train lines share a central stationof the city. Three bus circuits in yellow, pink and blue cover
three different resident areas quite densely and share the samestop in front of the main station. The buses are supposed to beoperated regularly in circle according to the timetable. But thebuses are often delayed due to the car traffic. Because there are
only three buses for the three routes, delays may accumulate toaffect operation in the next round especially on rainy days.
In that situation, bus arrival time becomes almost random topotential passengers. Some of them ring up the city hall in
attempt to know when the bus would come or just to complain
about lazy work of the municipal officers. The officers havebeen working hard to optimize the routes and to make thetimetable as precise as possible. They had to insert relatively
long time margin between the rounds in order to absorb thedelay and prevent its propagation to the next round. Thatmakes the bus operation less frequent and the bus service lessconvenient for the passengers. There seemed to be no solutions.
Fig. 2. Transition of fixed bus timetables to dymanic ones.

B. Toward dymamic timetable for community bus service
Tottori prefecture Bus Net [4] demonstrated how useful thereal-time bus location is for shortening the time to wait for thebus. Applied to the circular community bus service, the realtime dynamic bus timetable will allow us to forget completely
about scheduled timetables if we can only let the potential
passengers know when their bus will actually come.
Figure 2 illustrates the paradigm shift from fixed timetables
to dynamic ones. In the long past, we had no information
systems so that passengers could do nothing but patiently waitfor the bus to come. Then it became possible to measure delay
by detecting the bus passing by a stop via short-range radio sothat passengers became able to know how much the bus iscurrently delayed. Now it will be possible to track the bus all
the time by GPS and to give estimated arrival time at each bus
stop in near future.

The community bus service has an advantage that its
frequent operation in a circuit gives us plenty of historical data
to be used for estimation of arrival times. We can make use ofmachine learning or data mining to predict the arrival times asshown in Fig. 3 on the basis of current and past positions of thebus and the historical data.
C. System overivew
Figure 4 illustrates the overview of our system being
implemented. The system is composed of (i) GPS-enabled
Android tablet with a bus application for the bus driver, (ii)Central server, and (iii) GPS-enabled Android tablet with apassenger application for the potential passengers.
The bus driver selects the route on the bus application andcarries the tablet on the bus. That is all the driver has to do inaddition to driving the bus and taking care of the passengers.
The bus application keeps sending the current position to thecentral server via the 3G wireless data link.
The central server collects position data from the bus
application and estimates the arrival times at forthcoming stops
on the basis of historical data collected in the past. The
traveling times between adjacent stops constitute a featurevector in conjunction with other parameters such as weather
and calendar days. Given a vector currently available from thebus, the sever finds the closest vector in the historical data thatindicates the likely traveling times in due course.

IV.

Need of dynamic timetables for the community bus services
was addressed in this paper. A demonstration plan wasdescribed with the target field taken from a small city not sorural nor urban. The dynamic timetables would make thecommunity bus services more popular and convenient.
After reaching this goal, there would arise another problemof estimating the number of passengers since elderly people
would be interested in getting seats during the travel in case thecommunity bus is so successful and crowded.

The current and estimated positions of the buses arepresented on the passenger application as well as Web
browsers on PC.
D. Demonstration plan
We are now developing the server and application software
to be applied to the community bus service in the city of
Hitachi-Naka. It is yet to be known which algorithm ofmachine learning or data mining works successfully inestimation of arrival times.

Fig. 3. Predicted arrival times.

CONCLUSIONREFERENCES
[1]
[2]
[3]
[4]
[5]

Jordan, http://www.jorudan.co.jp/english/
Ekitan, http://www.apple.com/webapps/travel/ekitan.html
Navi Time, http://www.navitime.com/
Tottori prefecure, BusNet, http://www.ikisaki.jp/
H. Yamato and K. Tsubouchi, “On-demand bus system: A new public
transportation system which corresponds to users' demand,” Systems,
Control and Information, vol. 54, no.9, pp.342-347, 2010.

Fig. 4. System overview of dynamic timetables for the community busservice.