The Randall Museum in San Francisco hosts a large HO-scale model model railroad. Created by the Golden Gate Model Railroad Club starting in 1961, the layout was donated to the Museum in 2015. Since then I have started automatizing trains running on the layout. I am also the model railroad maintainer. This blog describes various updates on the Randall project and I maintain a separate blog for all my electronics not directly related to Randall.
2023-11-25 - Trolley Automation Experiment
Category RandallI’m currently experimenting with the preliminary design for the Trolley automation:
The main focus here is the Software Defined Blocks project which uses an ESP32 with sensors to emulate block activations for a train model railroad. I’m using this new automation as a test bed to experiment with that and different sensors.
Although the software part is progressing smoothly, the automation part is not, c.f. results from the automation first test.
After fiddling with it quite a bit, I got something that seemed to work. I left my prototype ESP32/sensor there to try it during the next day’s automation.
It failed apparently mostly immediately. I’m checking the logs to figure out why.
There are a few other logistic challenges that are independent from the sensor/software itself.
For example I have a handful of cameras to monitor the automated trains. One purpose is for me to check visually where the trains are when things are not working properly. I realize I have no camera that properly monitors the trolley. I have two of them vaguely pointed in that direction yet unfortunately the trolley line is hidden by a large pillar on one and by the window frame on the other. Thus this automation will require one more monitoring camera. I did not expect that, yet it’s a bit part of the automation work -- monitoring is half the work.
Another challenge is with the trolley engine itself. The engine selection is this orange trolley seen above. The model is Atlantic City #6885 from Bowser streetcar and it is a very good facsimilé of the SF Muni Milan 1815, part of the San Francisco Heritage Streetcar Fleet. This is a DCC model. It has a good sound and runs well.
However, #6885 is certainly a finicky DCC engine though -- folks who tried to run it on the layout keep reporting it tends to “not stop”. And that’s right: when running, it seems to ignore any “speed 0” stop command. However it is possible to easily stop it by switching the direction to the opposite, and then stopping it after a couple seconds. Go figure. Thus I coded that in the automation script it seems to mostly work.
On today’s run, the trolley completed the automation route just fine 5 or 6 times, then failed. I’m not on site and the cameras cannot unfortunately show me where it is, yet logs from the automation computer make it clear the trolley left and never reversed back to its original position. It’s possible that it hit some kind of dirty track or something as simple as that.
That’s on par with my other automation work -- each one of them took quite some time to set up and get to some decent reliability. There’s no magic bullet here. It takes work, and I fully expect this specific automation will take work to fine tune properly, independently of whatever sensor technology I use.