[ILUG-Social] Official Dublin BUS GPS info

[Paul Holt]

I asked Dublin bus about their GPS plans, and they send me this standard
response page, which I have reformatted for your convenience.

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Real Time Passenger Information System

What is RTPI ?

	Traffic congestion in cities makes it difficult for public 
	transport operators to deliver services according to 
	schedules. Disruptions to schedules have a negative impact 
	on the quality of service provided to the customer. This is 
	a universal problem, experienced in every major city. One 
	solution being deployed in many cities is the provision of 
	electronic information displays at bus stops, which give 
	the customer an estimate of the waiting time for the next 
	bus. These systems, commonly referred to as Real Time 
	Passenger Information (RTPI) systems, use a variety of 
	technologies to track the location of buses in real time 
	and use this information to generate predictions of the bus 
	arrivals at stops along the route.

Q-time

	Q-time is the RTPI system currently being implemented by 
	Dublin Bus. This is a pilot scheme operating on bus routes 
	in the west of the city. The purpose of the pilot scheme is 
	to evaluate RTPI in one sector of the network prior to 
	implementing a citywide RTPI scheme under the NDP.

What routes is Q-time operating on?

	The initial phase of Q-time has been implemented on the 
	Lucan QBC. Electronic displays are installed at key bus 
	stops on the QBC. The second phase will be installed on the 
	North Clondalkin and South Clondalkin QBCs during the 
	summer of 2001. Initially it is planned to have ten 
	displays on the Lucan QBC and fifteen on the Clondalkin 
	QBCs. 

Benefit to the customer

	The customer benefits from the elimination of the 
	uncertainty regarding the waiting time for the next bus. 
	The bus stop is equipped with an electronic display unit. 
	The information displayed indicates the route number, the 
	destination and the predicted number of minutes for the bus 
	to arrive at that stop. This information is updated every 
	thirty seconds.

How Q-time works

o	each bus, using the GPS satellite navigation system, 
	determines its precise location and transmits this to the 
	control centre every thirty seconds
o	the central computer compares the actual location of the 
	bus, at a given time, with its scheduled location
o	the central computer calculates the time for the bus to 
	reach all subsequent stops along the route, bearing in mind 
	the current bus speed and any deviations from the schedule
o	the central computer, transmits to the relevant display 
	units, predicted arrival times for the bus

The main components of the system are:

o	an on-bus computer with GPS receiver on each bus
o	central computer system, based at the depot
o	electronic display units at designated stops
o	a VHF radio system to manage communications between the 
	central computer and the buses and display units. 

The Q-time system was developed by a French company, GTMH.



Paul Holt