The FlyWay Shunting

If necessity is the mother of invention, how does one account for all the unnecessary stuff that gets invented?

Shunts will be needed: at nodes; places where beams meet and separate for sidings at stops; so that stopping cars won´t be in the way of those passing thru when branching out, where parallel beams are required in order to increase traffic capacity at crossings and roundabouts at station areas and terminals for manual servicing of the interior of the beams (see further down)		This is a rather technical page, but not so heavy. It only deals with the physical part of the shunting. The routing part, which is computer-controlled, is dealth with on another page. This page is still being written!

Figure 1

From a functional point of view, we have to divide the shunts into 2 categories: Those shunts where the beamcars don´t have to reduce speed Those shunts where some reduction of speed is required. Actually, it is not as simple as stated above. Reduce from what speed?

Every single shunt will, because of its design, have a maximum allowed speed. If a certain shunt is placed on joining (or diverging) beams that do not allow high speeds (whatever our definition of "high speeds" happens to be), then the beamcar can pass thru that shunt without reducing speed. If the same shunt is placed on beams that do allow high speeds, then, of course, that shunt would belong in the other category, the one that requires beamcars to slow down. The interested reader can read more about this on the page about "Shunts and shunting".

Figure 11. I n SwedeTrack's concept, it is not the shunt itself that directs the vehicle onto the correct track when it comes to shunting node and has to choose which way to go. Nor does the shunt perform the actual switching of the car. The computer at the shunt provides the car with information regarding the best choice of route considering the traffic situation at hand and the destination information that the car has provided to the shunt's computer. But the decision as to choice of route is up to the car's on-board computer. As regards the actual shunting, there is a control side and a mechanical side. The control side involves the computerized directive to the propulsion car to switch this way or that. This means that the car always has to know: exactly where it is where it is going how it is going to get there. The details of this are treated on another page. The mechanical side of switching is briefly explained here. Consider the pictures 11 through 13. In good time before the shunt, the cars retracts the 2 wheels that are on the outside of the turn. The wheels are lifted upwards, like a male dog peeing against a tree. After the shunt, the wheels are folded out again at the "touch-down" points. As an example, let's say that a car coming from the bottom at figure 14 (which shows a birds-eye view of the shunt) is turning right. The propulsion car (i.e. the the part of the vehicle that is inside the beam) will then retract the wheels on its left side (note the left wheels in the cutaway view in figure 12) before entering the shunt, and then fold them back out at point B in figure 13 after the shunting. The upper wheel (one on each side of the car) is needed in order to keep the car upright when going through the shunt. The right upper wheel presses against the inner flange in the ceiling of the beam as the lower left wheel is lift up, and vice versa (point A in figure 13). The area B in the ceiling in figure 12 can be used for electrical cables, waveguides, etc. As can be seen in figure 14 (a cut-through view from above), the distance to the touch-down points can be quite long, if the shunt is a "smooth" one. The behavior is no different in weaving and in diverging shunts. But the shunting (sometimes) has to go fast! FlyWay cars are designed to be able to exceed 120 km./hour! The "Frog" Problem As can be seen in figure 15 (which likewise shows a cut-through view from above), there can be quite a distance between touch-down points, and the area indicated with yellow cannot be supported in any way, neither from above nor from below; half of the supporting structure has to be removed. This is called a "frog", and we have written more about the frog problem on this webpage.

Figure 12. Figure 13. Figure 14. Figure 15.