Thursday, January 26, 2023

An automated point to point system

It's been a long time since I've posted here and a long time since there has been a chance to set up and run the AsiaNrail layout.  The last setup we had was at the Narrow Gauge Convention in Sacramento back in the fall of 2019.  During all this time with the pandemic my energy has been directed toward my American Prototype home layout.  But AsiaNrail now does have an exhibit scheduled for April, more on that in a future post.

Having something on the schedule has motivated me to get the modules out and get them ready.  There is one project that I have been thinking about for a long time and thought now would be the time.

The AsiaNrail layout always has several stub end branch lines and often there are not enough operators to have them running along with a continuous running loop.  I thought it would be great to have something that could automatically do a point to point run on one or two of the branch lines.  My experience with the Azatrax IR train detection products on my home layout lead to to try out their point to point controller. 

First step after I got the controller was to try it out on a temporary Unitrack setup.  The control circuit itself is the green circuit board to the left of the track.  I made some temporary holders for the IR sensors from wood scraps.  I had this running two different trains that would alternately go out from one of two spurs, go to the end of the single line and stop for about 10 seconds before returning.  The controller took care of the turnout and also has an adjustable momentum feature built into it. 

Being satisfied with the results of the test setup, I went about making this into a setup that could work on a modular layout.  The Hot Springs Junction module would be the base and would have the IR sensors permanently installed under the tracks next to the station platforms.  In this mode the detection is caused when the IR signal is reflected off the bottom of a train.  The sensors would be behind the platforms at the station so would be almost totally hidden when viewed from the side.  The overhead view below shows these sensors pointed out in green.


The sensors at the remote end will need to be on whatever module is at the end of the run.  I made up a fixture from brass to hold the sensors at the end of a 25 foot long cable.  In this photo it is shown in it's storage box along with other layout electrical hardware.

















The controller board was mounted in a plastic box with a clear lid so the indicator LED's could be seen.  This will hang on the leg cross brace under the module.  In this photo the lid has not been installed yet.  Connections to this control box are for power, the remote sensor and the main cable connection to the module.

















This small test layout using the Hot Springs Junction module and the two small single track modules was used to further test and experiment with this control system.  Because the turnouts on the Hot Springs Junction module were not wired as power routing, I was not able to make make this setup work the same way as the Unitrack test setup.  In the interest of having something ready for this next show, for now this is going to run just the one train point to point.  Later, when I have more time I will redesign and wire things to use the full function of the controller.