Sky-Cycle-Ways, Elevated bike lanes

This is the outline for a proposal for a new kind of elevated cycle way. The sky cycle way is an elevated cycle network which reduces time for travel for cyclists. This network turns any city into a flat Amsterdam or Cambridge. I believe this is the lowest cost for installation for any personal rapid transit system. By expanding on the understanding of the design and construction of monorails and other elevated transportation methods.

The problem

You can define the problem in many ways. You might look at this as a long term environmental problem. Can America afford the long term dependence upon oil ? Something which will inevitably run out ? Oil has become the key factor in the structure of cities such as Los Angels and Atlanta ( too name two). If all the alternatives to oil cost more then how is America expected to make a transition to this future economy ?

Alternatively look at the air quality of a City like Atlanta (here for PDF),In 1990 tons of nitrogen dioxide where dumped into the atmosphere by the vehicles per day. The current official target is to reduce this to 225 tons by 2004 and at the same time make Atlanta more mobile. If Atlanta means to grow this means having more people making more journeys and at the same time keeping the charge to the economy of Atlanta to the same or lesser value.

If you believe the concept of Air Quality is irrelevant then perhaps you should answer how America can afford to waste millions of dollars being stuck in traffic ? When you get to your destination can you afford the cost of the parking ?

Some new solutions

Historically the solution to transit was the introduction of so called Mass Transit. This involves pulling people together in buses, trains or Trams, this gain in by the economies of scale are frequently at cost to the convenience of the individual - they have to travel to the bus stop/station and board vehicles at fixed schedules times. Even High Occupancy Vehicle(HOV) or car pooling has had a comparatively poor uptake ( Atlanta's HOV lanes are relatively free).

One of the most recent developments has been the concept of Personal Rapid Transit. ( see http://faculty.washington.edu/jbs/itrans/ for a definitive list on PRT and http://www.atsltd.co.uk/ or http://www.SkyTran.net/ for an assortment of alternative proposals ). The basic notion is to make a train as personal as a car. You dial a 2 or 4 seater vehicle, it arrives and takes you directly to your destination. One possible summation of PRT transportation system is.

  • Considerable time can be saved if the train does not stop from the start to the end of a trip.
  • Journey times can be reduced by automatic steering, this can me no stopping at junctions or the ability to use the faster reactions of the computer to run vehicles closer together.
  • The introduction of a elevated ( or lowered ) system is in effect potentially doubling the number of streets available for movement in a city without doubling the size of the city.
  • Monorail solutions don't shadow the street as badly as full elevated rain ( think about Chicago near the loop).
  • Personal Rapid Transit (PRT) systems don't use massive trains so reducing the size of the track and so lowering the installation costs compared to an elevated route.
  • Any raised system has less expense over ground rights.
  • Any raised system can be run with out blocking the current road network - unlike a ground based light rail system or introduction of large numbers of busses.

I'm not going to jump into a critique of PRT systems - I think if skillfully introduced they gain from the same kinds of networking benefits the Internet or the phone system does. By having a larger network the potential trips grows at the square of the number of stations. PRT systems also have the possibility of lowering costs, buy removing the need to have 'accompanied' cargo. If every shop and supply center could be linked by an automated cargo transportation system then potentially the delivery of objects would drop.

If I might I would like to look beyond the basic needs of transportation and add in an extra component. Another problem which is growing across American and is quite prevalent in Atlanta is obesity. Obesity according to the Surgeon General quickly becoming the number one killer in America. If you look at the Center For Disease Control statistics, heart disease is the number on killer on the loose in Atlanta and Georgia.

Principally one of the problems with any mass transit system is that the less dense the area gets the harder it is for public transport to provide a decent level of service. Brian Richards suggests a cut off point beneath which it is impossible to provide a bus service. In the case of light rail systems like MARTA, the problem is getting people to the stations from the region around the station. One solution park and ride means getting the car out to ride to the station, while this expands the area which fan 'feed' a train station. It also means that the car is being used at the worst part of it's pollution cycle - during the first 5 minutes on when the cold engine is at it's most in efficient.

Sky Cycle network

I would like to propose that a solution which has not received enough consideration is that of a integrated cycle network which has a component which consists of a raised cycle ride ways. This elevated cycle path functions like a freeway/highway/motorway for cars. My argument is that raised cycle paths have the the visual impact of a monorail. The argument is that over head cycle ways should be considered Personal Transit System which uses bicycles as the 'carriage'.

The central logic behind a fully cycle network is to produce the cheapest possible raised transportation network. With monorails the way to do this is to reduce the amount of metal or concrete in the air. The less material in the air, the further legs can be spaced, and the more insubstantial each leg becomes. The less matter in the air the less right to light issues ( read costs ) are incurred to the project.

There have been some suggestions for a mixing of suspended bicycle ( http://faculty.washington.edu/jbs/itrans/skybike.htm ), I would like to go one stage further and suggest a fully raised cycle network. This is fine ( I could imagine a really nice network like this for a theme park it would be great). For an urban commuter context I would argue that keeping the bikes attached to the tracks looses the natural efficiency gained by having a form of transport available to get you to the station.The logic behind this is to gain a larger buffer around the stations which can extend the collection area for the network.

Secondly one of the advances of PRT are that smaller vehicles generate less nose and intrusion. In both cases it is necessary to reduce the weight of the vehicle in relationship to the weight of the passengers. One of the few cases where the vehicle weight is less than that of the passenger is the case of the bicycle. This should push the system to be it's most efficient and there for most cost effective way of moving people from the road network. Remember I am not suggesting we remove all cars from and Atlanta and replacing them with bikes, if I was then the elevated component would not be needed. Instead I am suggesting we can reduce travel times for those relatively close to their work locations ( within 5 to 10 miles ). This removes people from the roads completely and so frees up space to so help reduce congestion for those who live further out. Notice like a monorail,PRT or the underground MARTA system this does not involve interrupting the road network or have any other service which is competing

Ok that's cycle network as Personal Rapid Transit system. Now lets look at the whole thing from the traditional cycle network. When surveys are done the list of reasons people don't cycle to work is something like

  1. Danger - Cycling on the streets competing with cars is perceived to be a dangerous affair.
  2. Exposure - Cycling in the open exposes the passengers to wind, rain and the heat of the hot sun.
  3. Work Load - Cycle networks are much more popular in relatively flat cities like Amsterdam, or Cambridge. Hilly cities have problems.

Danger is the first and most pressing problem. If you think this is a concern then ask your self one question. Are you happy letting children ride on the streets ? I think the test for a design safety must be are you happy children cycling ?

In fact there are situations when people are happy cycling, when they are using a segregated cycle road. Fitting a segregated cycle network back into a city is a very difficult thing to do. If it is done then the cycle routes are chosen and a available basis rather then the kinds of engineering methods used by planners for roads. Like a light rail network working at at grade network into an existing city plan means interrupting both the road and the light rail network to the detriment of both.

For the same logic that drives the a metro system underground or above ground ( in the case of a Monorail). I propose we must make available in addition to a well integrated, separated cycle network.

A raised cycle network, the logic is similar to the existence of a freeway network for cars. While a cycle network will work at a different scale, the underlying logic is the same, introduce long runs of uninterrupted motion. This reduces two things, firstly like any PRT, reducing stops between the origin and destination reduces travel time or increases average speed. Secondly which is an added benefit to a cycle network, not stopping and starting means the amount of energy necessary to go from origin to destination is reduced.

 

 

 

 

notes

info on oil running out.

http://www.eia.doe.gov/pub/oil_gas/petroleum/presentations/2000/long_term_supply/sld012.htm

http://www.railroadingamerica.com/ ( anti rail lobby )