Does it Really Pay to Bunch People Together?

Figure 6:3

Figure 6:5

he motive for using vehicles with bigger cabins is, as stated, to increase passenger-hauling capacity on the beam. Thus, we already have all timeslots filled; the beam cars travelling as close together as permitted, considering their speed. Small cars which stop along this beam have this stop as their destination, and are in no hurry to get out on the beam again. If they leave empty, they can usually wait until the traffic situation eases up a bit. Big cars are more likely to stop in order to exchange passengers, and then get going again, as soon as possible. So, in order for them to get back out on the beam within a reasonable amount of time, there has to be a reduction of other traffic so that there are empty timeslots every now and then. It is a bit like getting out on the highway when traffic is heavy. If you force your car out, cars behind you will have to slow down in order to create the necessary safety distance between yours and their vehicles. Thus, on the beam, we either have to slow down other traffic to let the departing car out, or we create empty timeslots. Creating empty timeslots is the preferred way of handling the situation in an automatically controlled traffic system. Either way, we just have to reduce traffic capacity on the beam to accomodate these stops. This is illustrated in figure 6:5 above. View A shows the situation where all slots are filled with beamcars. If we now have to let a beam bus out on the beam, a bus which has to stop at all the stops numbered 1 through 4, to either let off or take on passengers, we get the chronological scenario shown in the other views. In view B, Node A has to block two timeslots from being used by other cars, so that the bus can re-enter the beam from stop number 1. In view C, Node A has to block two more timeslots, so that the beam bus can re-enter the beam once again, from stop number 2, and so on. We thus find that: The higher the number of vehicles that have to stop along the way, the more empty timeslots will have to be created. The more passengers there are in the vehicles, the greater is the likelyhood that they will have to stop along the way. The more passengers there are in the vehicles, the more often they will have to stop along the way, requiring more empty timeslots. Solitary empty timeslots will not suffice, for safety reasons. They need to come in bunches of two or three, meaning that a heavy vehicle will take the place of two or three small vehicles, with typically 6-8 passengers.

In this manner, big vehicles "steal" traffic capacity. So; how should one best allow for this? Well, in automatically controlled traffic systems, there are two alternatives: The computers can calculate with statistical averages; where and how often the big vehicles will stop, and how long the stop will take, and generate a suitable number och timeslots by holding back other traffic. The computers could collect data from all travellers in these vehicles on-the-fly and calculate which vehicles will stop where, and when, and estimate how long the stop will be, and allocate empty timeslots for this need. This option will save timeslots, but since it cannot be calculated exactly when a vehicle is ready to leave, a safety time-margin would have to be added, meaning that the departing vehicle would have to wait a few extra seconds. As a simple summing up; letīs say a big vehicle takes 16 passengers. It will take the place of 1.5 small vehicles (since itīs heavier and requires a slightly longer safety distance). It will make 4 stops along the way, requiring 2 empty timeslots (as in figure 6:5) or maybe even 3 timeslots to get going each time, at departure time. So, when reaching its final destination, taking longer time than small, direct taxi-style vehicles would have taken, it will have "stolen" the traffic capacity of 1.5 plus 4 times 2 = 9.5 small vehicles, or 1.5 plus 4 times 3 = 13.5 small vehicles. Those 10 or so small vehicles could have conveyed up to 10 times 4 = 40 passengers directly to their destinations! Naturally, it is not quite that simple. Neither big nor small vehicles are likely to have all seats occupied at all times, nor even most of the time. The small vehicles which were excluded here (because of reserved timeslots) would more likely be carrying just 1-2 passengers, making about 10-20 travellers in total. But the big vehicle which was the cause of their exclusion? Probably not more than 10 passengers, most of the way, if its capacity is for 16 passengers or thereabout. The big vehicle would (maybe) be filled to capacity before departure, but passengers getting off along the way are not likely to be replaced in full by other passengers. The reason is of course that these vehicles are used to get people home from work att rush hour. In the morning rush, we would have the opposite situation, of big vehicles running with mostly empty seats most of the way, in order to accomodate those travellers that are waiting at stops along the way. One can thus see that, capacity-wise, big vehicles would have to be really big (maybe carrying 32 passengers!) in order to be motivated at all. Conclusion; Beamcars that have to stop along the way are seriously detrimental to beam network capacity!

There is something fundamentally wrong with timetables: they create stress! People who rely on public transport to get around constantly have to keep an eye on the clock. If they miss a bus or a train, they will have to wait for the next bus or train, going the same route. Waiting alternates with stressful moments, where you have to rush to make it in time the the busstop or train station. Everywhere around public transport stops one can see people run around like ants, sometimes tripping over each other. There was never anything like this before urban transports were invented. Up until about 100 years ago, people lived their leisurely life, not paying much attention to the clock. Life might have been poor and laborious, but it was never harried. And one need not be a physician to realize that todayīs urban harried lifestyle is not good for the human body. Ants might be created to dash about, but not humans. Compare ordinary subway stations with, for instance, Londonīs Docklands Light Railway, where cars keep coming like on a conveyor belt. You donīt see people running to those stations; they know they wonīt have to wait more than a couple a minutes before the next, driverless, car arrives to the platform. The transport alternative that we, at SwedeTrack System, are proposing on these webpages does away with this lifestyle. Life in urban areas can become so much different when transports are always available, everywhere, with no need for the travellers to check any timetables. Not only can we create silent, exhaust-free cities, but also cities where people can take it easy, and move about at their own leisure. Now, wouldnīt that be something worth striving for?

Planning for Economy and Capacity he question we want to answer here is "does it really pay, capacity wise, to bunch people together, rather than letting them ride in small vehicles?" We need to look primarily at 4 criteria: Usage versus investment in beams, beam supports and other stationary equipment. Usage versus investment in beam vehicles. Public appeal. If travellers shy away, the beam network becomes a not-so-good investment as it could have been. From the operatorīs point of view. Letīs look at each of these in turn. Usage versus investment in stationary equipment Figure 6:8 Figure 6:8 above shows estimated investment costs (in millions of $US) for beams, supports and other fixed equipment. Massproduction reduces cost per length in the manufacturing and also in the assembly process, out in the field. As a rule of thumb, costs are reduced between 15% and 20% for each doubling of the serial length. We have calculated for these two percentages, and compared costs between 3 sizes of beams. The starting points are costs for short networks for demonstrations purposes, and for short runs, such as between a city and an airport. As can be expected, the lightest beams come cheapest, but the difference between all these costs gets progressively smaller for larger production series. The reason is, of course, that total costs can be divided into material costs and production costs. While production costs per unit decreases for long manufacturing series, material cost per unit stays about the same. For long series, material costs thus become a progressively larger part of the unit cost. Percentage-wise, the extra material that goes into sturdier beams and supports is small, and therefore the curves for the three beam-categories tend to approach each other for longer production series. The best conclusion from this is probably that one should not build sturdier beams than are called for. Wherever one can make do with small vehicles, one should not invest in larger beams than needed, unless the network gets so huge that mass-production cost-reductions make the cost-difference between small and large beams of minor importance. One should reserve large beams for trunk lines and industrial areas. The general aim is, of course, to have as much traffic on the beams as they can handle. This is an argument for few beams and heavy vehicles. But, as noted further down, it is also important to, in time, arrive at a fine-meshed network, in order to attract travellers. This means that much traffic can be re-routed along more or less parallell beams. As a consequence, the number of beams between two arbitrary points will ultimately be so many that they can provide the necessary capacity, using only small vehicles. Thus, with sensible planning, the need for large vehicles should be marginal. An Economical Example Letīs look at some figures and see where we arrive. From the diagram in figure 6:8 we can get some approximate figures for relative cost: Length Heaviest beam Lightest beam Quotient 64 9.0 2.5 3.6 128 7.5 2.0 3.75 256 6.0 1.5 4.0 512 5.0 1.0 5.0 So; it would be relatively fair to say that the heaviest beam would be about 4 times as expensive as the lightest, for reasonably extensive networks. It should be pointed out that we are not concerned with expenses for station platforms here, as FlyWay do not need any. Itīs clear that sidings at stations will cost a lot, but that wonīt affect the 1/4 ratio in this example. Clearly, then, for a limited amount of money, One could get about 4 times as much lean beams for smal beamcars, than heavy beams for big beambuses.

Usage versus investment in beam vehicles ere, it is clear that one would want as large vehicles as possible, since the cost-per-passenger of such vehicles would be the lowest. But; one also wants to maximize number of passengers multiplied by transport distances in as short a time as possible. Or, in other words, one wants: - every seat occupied - high average speed - keeping the vehicles busy as much as possible; no idle time. Small vehicles will be much easier to keep busy, they can run efficiently even at low traffic times. So, considering what we have said above, small vehicles win out on all three counts here. They are quicker and easier to fill, they accelerate faster and do not stop along the way, and they can be kept busy around the clock. However, we are just talking about investment costs here, since operating costs are not much different between big and small vehicles. And, since huge production volumes tend to narrow the cost gap between big and small vehicles (as is the case with the beams), the cost difference between big and small vehicles is not a big issue. One could easily let passengers who prefer to travel in small vehicles, pay a little extra for that privilege. The diagram in figure 6:7 indicates that there is a huge difference in carrying capacity between big and small vehicles. But this is measured as number of passengers passing by a certain point along the beam, at a certain speed. And that is not the whole picture. It applies only to trunk lines, where there are virtually no stops along the way. Figure 6:7 The diagram in figure 6:7 above makes a comparison in passenger handling capacity between 3 types of beam vehicles and also, for good measure, 3 kinds of road traffic. 1: Beambus with 32 seats. 2: Beambus with 24 seats. 3: Beambus with 16 seats. 4: Spacious beamcar with 10 seats. 5: Spacious beamcar with 6 seats. 6: Spacious beamcar with 4 seats. 7: Beamcar with 3 seats. 8: Beamcar with 2 seats. 9: Beamcar with 1 seat. 10: Road with 3 lanes. 11: Road with 2 lanes. 12: Road with 1 lane. Assumptions: - Average speed for all vehicles is 72 km./hour. - All passengers are seated. - For categories 1 through 6, 75% of seats are regarded as occupied. This is a statistically reasonable figure. - The small cars (categories 7 through 9) are individually booked, and will assumed to be fully occupied. - The road vehicles are assumed to have 1.3 riders each, corresponding to the actual situation in Western countries today. Small vehicles travel directly from start to destination, as taxicabs do. With large vehicles there is a reduced likelihood that this can be done. They have to serve a few stops along the way, and exchange passengers, thus considerably reducing their average speed. Thus, large vehicles should be reserved for use on trunk lines, where there are at least 5 kilometers between stops, as exemplified in figure 6:9. Since passengers should never have to transfer between vehicles (if they donīt want to), this means that heavy vehicles whould serve their best purposes travelling non-stop between heavily-trafficed downtown stops, and big centers in far-off suburbs. Generally speaking, they do their best performance at long-distance high-speed travel. Figure 6:9

he simplified example in figure 6:10 illustrates in a better way why small cars will dominate more and more over time, as the beam network grows. We will here assume that people are evenly distributed in the two areas A and B, and these two areas can both be a medley of residential neighborhoods and work places, so rush hour traffic would be equally heavy in both directions, along the trunk beams. Thus, a new network will consist of the trunklines (black) which can take big cars. These big cars can (presumably) handle the workload most efficiently, and earn revenue.

As time goes, and the beam network grows, there will be some extension of the big beams, which can handle heavy vehicles. But mostly, the network growth will consist of light beams (shown in blue in the illustration) which can only handle small cars. As can be seen, about 3/4 of all stops (indicated by red dots) are along the narrow beams, and with an even distrbution of travellers, about 3/4 of all travellers will use those stops which only can be served by small cars.

As the network grows and, over time, becomes finer-meshed, narrow beams and small cars will dominate he scene even more. Since travellers wonīt be changing cars during their travel (from small to big cars for travel along a trunk, and then back again to small cars), the dominating traffic on the trunkline will more and more consist of small cars. This will be a natural consequence of the fact that it will be much cheaper to expand the beam network by using narrow beams.

From the Travellersī point of view		From the Operatorīs point of view A private operator wants most of all to turn a tidy profit. A public operator wants to serve the public with good transport. Important points here are: Reaching as many prospective travellers as possible. This is best done with the lightest beams, which give more beams for the money, as we have seen above. Providing as much transport capacity as possible. This is best done with big beamcars. Attracting as many travellers as possible. This is best done with small beamcars. Charging as much per traveller as possible. This is best done with small beamcars, which can provide the best travelling comforts, such as speed and availability. Ease of administration. This is best done with small beamcars, which travel on demand, lika taxicabs. Beambuses have to be tracked more closely, to see that they travel where they should, stop where they should and are optimally used. Flexibility, to allow travellers and goods distributors to use their own vehicles. This is best done with large beams, which can take heavier loads. But on the other hand, such a network would be much more expensive to expand. A network of mixed beamsizes would be optimum. The operator, then, would prefer to have a network consisting of strong beams, capable of carrying heavy vehicles. But he would prefer to build with lean beams, since this is quicker, cheaper and less intrusive on the environment. So; the operator would have to weight pro and cons for each new phase of the networkīs expansion.
Public appeal There are 6 heavy factors that will attract travellers to a beam traffic system: Round-the-clock traffic. Can only be efficiently run by small vehicles, since, at night, not many people are out there. A network which comes close to their neighborhood. Fine-meshed networks cost money, and it is rarely motivated to build them for anything but the lightest vehicles. Privacy. Most people are prepared to pay extra to be able to ride in their own vehicle, possibly with friends and family, but not with strangers. Speed. Everybody, except sight-seers, wants to get to their destination as quickly as possible. No stops or detours along the way, please. Comfort. A well-designed transport system has sufficient seats for all travellers. Economics. When there are no drivers to pay, the fares will get lower.	Lean Transit The concept of Lean Transit is also becoming more popular. The term is inspired from the concept "Lean Production" and means that the emphasis is put on the travellerīs efficiency, rather than the effective use of the vehicles. The vehicle waits for you instead of - as is usually the case with public transport today - you have to keep track of timetables. Interested readers should study "Applying Lessons from Lean Production Theory to Transit Planning". In this report, we can read that: The main impediment to continuous flow is the tendency to batch operations. Most current transit technologies move passengers in batches, due in part to an intuited but incorrect sense of efficiency. Passengers are gathered in groups and temporarily stored at stations. Trips occur according to a preset schedule that is optimized to make the most efficient use of the equipment. Lean planners understand that this emphasis on the use of equipment rather than production flow (passenger flow in the case of transit) creates waste in the value stream as the final product (a trip) is created. In the case of transit this waste (usually wasted time) impacts the passenger immediately. I.e. from a Lean Transit point of view, it is a waste to let passengers wait at stations. They want to be travelling, not waiting. You can read more on the Advanced Transit Association website. All these considerations favor small car operation. The best way to attract travellers is by offering small, private-service vehicles, at all times. From the passengers point of view, large vehicles are almost never desired.

No big vehicles, then?

ne certainly should not rule out big vehicles completely. They do decidedly increase beam capacity, and might be needed whenever the network has insufficient capacity, such as during the expansion phase at a new location. If one makes a simple calculation, based on whatīs been said above, one could use these figures: - 0.5 secons headway between 4-passenger-vehicles, versus 1 second headway between 16-passenger vehicles. Assuming that they are full, the bigger vehicles in this example would be twice as efficient in hauling passengers. At the cost of sturdier beams and supports, etc. 32-passenger vehicles might be four times as effective. Not all seats would be filled, but, in fairness, also the small vehicles would have empty seats most of the time.

But this extra capacity would only be needed to enhance the capacity of a beam network that otherwise would not have sufficient capacity. For a growing network, this would happen during the expansion phase, before there are enough beams to provide alternative routes. But does it make sense to invest in sturdier beams and supports, and larger beamcars, rather than using these same money to instead expand the network (with parallel beams if needed) so that it does have sufficient carrying capacity for small cars to handle the traffic"?

For a "fully grown" beam network, large vehicles would only be used: On trunk lines carrying heavy traffic most of the time. During rush hour. Summing up this discussion, big vehicles might be needed: During the expansion phase, to provide needed capacity and to earn revenue for continued expansion. To haul freight To use along trunk lines, maybe only at high traffic times, to increase beam capacity. Thatīs about all that big vehicles are good for, in driver-less traffic systems.