Garden Railway Forum

Now that my workbench is clear again I thought I'd check over my first loco. It hasn't been run for a year or so, the track has fallen into disrepair, and I was making a big push to finish the live diesel...



This loco has a Picaxe based automatic speed control, that is set to control the speed to a scale 10 mph. The system uses a keyfob 433 MHz set to start - stop - sound whistle. The loco has two mini/micro servos in the bunker. Reverse control is manual.

The battery longevity is great, eneloop AAA hold their charge so well.

here's a short video of the sequences:
https://www.youtube.com/watch?v=IfBONSmWGec

That's brilliant. Now mount a barcode scanner underneath and you can scan barcodes placed between the tracks so that the arduino can decide the best speed for the next piece of track or stop at a station for a given time.

thats rather impressive, how does it cope with reaction times to gradients?

Question; how do you measure the speed of the engine?

The wagon has an optical counter, counting an axles rotational speed.  When the train slows down, the regulator is opened a notch, the controller waits to see if speed picks up, if not then the regulator is opened up another notch.  When the train is above speed the regulator returns to it's running position.  Then afterwards if the train is still over speed then the regulator closes one servo step per second, until finally the train is under speed.  And, so on.

The parameters that I have used are suited to my line.  My line has quite large radius curves and gentle grades, except for the final 180 degree return curve, but that's downhill.

Here's my best video showing a circuit of my layout, with a heavy test train.

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The construction of the R/C control, automatic speed control is detailed here:

http://www.santacruzlumberco.com/MLS_PD ... Steam.pdf"

Sounds a bit like the European Rail Traffic Management System in miniature without the collision control

Cheers,
Peter in AZ

dewintondave:113419 wrote:The wagon has an optical counter, counting an axles rotational speed.  When the train slows down, the regulator is opened a notch, the controller waits to see if speed picks up, if not then the regulator is opened up another notch.  When the train is above speed the regulator returns to it's running position.  Then afterwards if the train is still over speed then the regulator closes one servo step per second, until finally the train is under speed.  And, so on.

The parameters that I have used are suited to my line.  My line has quite large radius curves and gentle grades, except for the final 180 degree return curve, but that's downhill.

Here's my best video showing a circuit of my layout, with a heavy test train.

https://www.youtube.com/watch?v=Jq4MbCBAF6Y

The construction of the R/C control, automatic speed control is detailed here:

http://www.santacruzlumberco.com/MLS_PD ... Steam.pdf"

Your link to the pdf is broken?

Boustrophedon:113431 wrote: Your link to the pdf is broken?

Oops, try this:

Cruise Control Live Steam.pdf

Best wishes,
Dave.

That is extremely interesting. I do like the idea of minimal RC control without a great big box to hold.

Wow i really like this concept, though it is way beyond the capabilities of me to be able to fit, do you know if any UK company's or individuals could fit this system to locos?
cheers
Joe

It would be great if someone commercialised this sort of thing. But, most people are happy remote controlling their locos.

Best wishes,
Dave

Following your example, I am trying to build a speed controller for the little Houston Gate diesel shunter. I am using an 8 pin H bridge motor control chip and will use PWM to control the speed of the motor. I am hoping to get it onto one PICAXE protoboard.

Boustrophedon:116157 wrote:Following your example, I am trying to build a speed controller for the little Houston Gate diesel shunter. I am using an 8 pin H bridge motor control chip and will use PWM to control  the speed of the motor. I am hoping to get it onto one PICAXE protoboard.

Excellent!

I converted our LGB shunter to battery power and have a 1 Amp PWM speed control made from a hobby kit, it's a bit of a howler. I bought a couple of PWM controllers from eBay to control my big diesels headlight. I could try one in the LGB loco to see if it's better, the rotary control does incorporate a switch.

I am now using the LGB loco as a speed limiter on live steam hauled trains!

Best wishes,
Dave

Boustrophedon:116157 wrote:Following your example, I am trying to build a speed controller for the little Houston Gate diesel shunter. I am using an 8 pin H bridge motor control chip and will use PWM to control  the speed of the motor. I am hoping to get it onto one PICAXE protoboard.

Have you seen Greg Hunter's website on using these controllers with Picaxe? - http://www.members.optusnet.com.au/satr/RC.htm

It's amazing what he's been able to fit on to one 8 pin Picaxe chip - r/c speed control and sound. Here's an example of one of his 8 pin Picaxe r/c controlled locos running on the PLR when he and his wife visited in 2014 - https://www.youtube.com/watch?v=7FzLNcwfUD4

Rik

ge_rik:116168 wrote:

Boustrophedon:116157 wrote:Following your example, I am trying to build a speed controller for the little Houston Gate diesel shunter. I am using an 8 pin H bridge motor control chip and will use PWM to control  the speed of the motor. I am hoping to get it onto one PICAXE protoboard.

Have you seen Greg Hunter's website on using these controllers with Picaxe? - http://www.members.optusnet.com.au/satr/RC.htm

It's amazing what he's been able to fit on to one 8 pin Picaxe chip - r/c speed control and sound. Here's an example of one of his 8 pin Picaxe r/c controlled locos running on the PLR when he and his wife visited in 2014 - https://www.youtube.com/watch?v=7FzLNcwfUD4

Rik

That's the sort of thing, but I will not be using a relay.