How to make a trolley pause?

[8ntruck]

I've got a Polar Express trolley that I want to add into my Polar Express layout.  I'd like it to pause at either end of its track.

Anybody got any thoughts about how to make this happen? 

My initial idea involves a switch of some sort on the bumper at the end of the track, a timing circuit, and a relay.

Thanks in advance.

[lionelsoni]

What reverses it now?

[EIS2]

I had a circular track and used the 153IR controller to pause the trolley.

https://www.youtube.com/watch?v=_73maZWe07A

Earl

[8ntruck]

Bob - Good question.  I haven't had the trolly out of the box until last night.

The new trolley looks like it has an electronic reversing unit.  Will need to take the top of the car off to be sure. 

Both bumpers are spring loaded and return to the extended position, making me think that they trip a switch to cycle the reverse unit. 

This opens up the possibility of adding some sort of time delay on board the trolley.  Some sort of R-C circuit?  There is probably a timing chip out there somewhere that would work, too?

Got to remember that I'm a mechanical engineer who knows just enough about electronics to be dangerous.......

[lionelsoni]

Here's an idea that might work:  Put a stop block, that is, an isolated piece of center rail, at each end of the trolley's track.  Put a control rail, that is, an isolated piece of outside rail somewhere on your Polar Express loop, connected to a relay which switches on both stop blocks whenever the train passes that point.

The trolley will run to the end of its track, stop on the stop block, then start up again when the train reaches the control rail, and run to the other end of its track and stop.  Then, the next time the train reaches the control rail, the trolley will start up again and return to the first location.

Each time the trolley starts up it will be in the same direction that it was traveling before it stopped, until it hits the bumper.  By adjusting the bumper position close to where the trolley stops, you may be able to minimize that little unwanted motion.  If the pause is long enough, the trolley's electronic reverser may actually go to its default direction, which will be correct for at least one end of the track.

It's also possible that the reversing unit also responds to track-voltage interruptions, just like a two-position e-unit.  In that case, it should start up in the reverse direction, which would be ideal.  If it ever gets out of sync, the bumpers should correct it. 

[BigAl 956]

A lionel 132 start/stop station or signal would probably work.

[8ntruck]

Good ideas all.

I've already got low voltage DC on the layout, so that makes Bob's relay idea easy - DC relays are easier to find than AC relays.  I don't really have a place for a stop station or signal that Al speaks of, but the guts from one of those would certainly work, and could be hidden inside the scenery.

I'll keep you updated on my progress.  The next show for the layout is the 2nd Saturday in December.  I'm wanting to get it done by then.