I embrace the “in vehicle” switching philosophy, which is found in designs by J. Edward Anderson and others. I can see little logic for moving the track, as is the case for ordinary trains. This design, however, has generally involved a “bi-stable” guide wheel positioner, wherein one steering guide wheel always remains engaged. This prevents a situation where the vehicle is neither directed left nor right, and so crashes into the middle of splitting tracks. The problem, however, is that if the vehicle is going at high speed, maybe with no turns in sight, the small steering guide wheels end up racing for no reason. An obvious remedy for this is to have the engaging “fin” within the track be discontinuous. That way, one wheel set will still be in the engaged position, for safety, but it will not have any running surface to engage to with, at least when on the straightaway. There is no needless spinning.
In the picture above the running surfaces for the steering guide wheels are shown in blue. Because of expansion and noise, the running surfaces should be finger-jointed and rubber mounted, so making them discontinuous and tapering them into and out of contact position is not a problem. (This detail is not shown)
This results in a different problem, however, also exacerbated by higher speeds. The steering wheels, if not engaged, cease spinning. Then, upon re-engagement, they would have to go from zero to thousands of RPMs in an instant, which would tend to tear them up. They must, therefore, be caused to spin prior to engagement with the running surface, and preferably at exactly the correct speed.
There may be some motor and controller out there what would work, but my guess is that it would be very, very expensive, and way over-built. These wheels need only spin. They don’t actually need to drive anything, even thought the monster shaft size would be consistent with delivering the power of a midsize motorcycle. I say make our own.
The “motor” shown above is a simplification. Additional electromagnets can be added. Now I don’t know a whole lot about digital electronics but I have bread-boarded some simple circuits and I know that if there is a source of pulses (such as the encoders I discuss in post 20) the frequency can be easily manipulated by simple means such as a J-K flip-flop, (a basic building block chip, available on Ebay, for example, for about 20 cents) This output can trigger a $5. solid-state relay and Voila! A simple motor. Again, I am sure someone else could come up with a much more refined design but I think the principle is sound. Maybe I should market this idea to Boeing or Airbus. Ever see how those landing wheels smoke when they hit ground?
