Solving the Urban Transport Problem with an Automated Guided Vehicle (AGV)

by Jack Cawkwell

August, 1999

I have attempted to solve the transport problem by abstracting a set of user requirements of a passenger transport system. In doing so the focus is not on the problems of the transport system, but on what is required of it

It is well known that transport is vital to western industrial society, and the transport system faces serious problems. The burning of fossil fuels in the transport industries produces a significant proportion of the green house gases that cause global warming. Congestion in and around cities is reducing the quality of life of city dwellers, and reducing the capacity of societies to develop. The demand for transport is increasing, and expected to increase as people become more affluent. Large newly developing countries which have only recently begun to adopt the motor car and other modern transport systems, can only worsen the global pollution problems.

Previous attempts to help resolve the transport problem have partitioned the transport system into a large number of distinct problems, each of which might be solved by a particular technology. Congestion can be solved by building more roads or tracks, pollution can be solved by better engine technologies and improved efficiency, demand can be choked off by tolls and taxes. These band-aid solutions rarely solve the problem in the longer term, as the demand for transport appears insatiable. Other solutions are often big systems that require massive commitments in capital and town planning, and are often never implemented.

Many of the problems of the transport industry are caused by individual travelers making appropriate transport decisions for themselves, which collectively cause problems. The clearest example is the motor car. Once purchased, the economics of ownership make it the cheapest and most convenient form of transport for the owner, but collectively the externalities of congestion and pollution cause problems for society as a whole many of whom are car owner drivers. The user requirements are drafted to specify that the transport system provides the transport needed, but in a way that avoids the economics of ownership that spoils the social value of the private car.

The basic user requirements extracted are:

cheap -- if it is expensive travelers will not use it

environmentally effective -- a polluting system is not sustainable, and impacts quality of life

safe -- an unsafe system is not acceptable

available on demand -- ideally travelers will not wish to wait for service

point to point (rather than station to station) -- travelers may not be able to get to a station

journeys up to 10 miles (16 kilometers) -- existing modes can provide for longer journeys

computerised pricing -- to support flexible pricing to manage demand

compatibility with existing modes -- supporting not competing with existing modes

An outline design is deduced from these requirements. It is a very small taxi with one or two seats. It is an automatically guided vehicle (AGV) running on a normal road surface but with no other motorised traffic. ( For an operating example, see the Parkshuttle page). It has sufficient vision based obstacle detection capabilities for it to drive safely in otherwise pedestrian areas. The vehicle follows a simple visual track painted on the road surface. The intention is that passengers will make short journeys using the AGV, which will transport them around a small urban centre. For longer journeys the passenger will travel by AGV to a bus, or railway station, and at the far end take another AGV to the final destination. The use of computers will assist travelers in planning their route, and the system as a whole to avoid congestion and waiting. Travelers will be able to order an AGV, perhaps using a mobile phone, at any point on the visual track.

The technology to cheaply provide guidance and obstacle detection is designed, and a simple demonstration prototype has been built. I have specified a full size outline design which meets all the basic user requirements. There are other AGV systems suitable for use in this way, but I believe that the technology I have developed is significantly cheaper.

This AGV technology is easier to deploy than big light rail networks, as the only track modification needed is the visual marking of the existing road surface. This would enable small trial schemes to be experimented with at very low cost and little commitment. Schemes could be experimented with at off peak times such as weekends and nights, and returned to normal traffic at other times. In a similar way a successful small trial could be expanded rapidly by marking more road space.

In practise the AGV taxi will provide a different service in urban centres and urban fringes. In urban centres passengers will be collected and put down at stations. This is necessary to avoid the problem of AGV's stopping in busy routes to pickup and put down. At the urban fringes there will be fewer stations, and less AGV traffic, so it will be possible to pickup and put down any where on the network. It is this dual role that fixed rail systems cannot address. At the fringes of the urban centre the provision of public transport becomes sparse and expensive to provide, travellers need cars for the urban fringes, and then use them for as much of their travel as possible.


Last modified: August 18, 1999