Servo controlled semaphores

ge_rik

ge_rik

British narrow gauge (esp. Southwold and W&LLR)
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Following-on from GregH`s thread about semaphore signal bounce, I have now been able to apply his excellent Picaxe program to controlling the first four of my semaphore signals. Sorry about the video, it is mildly more interesting than watching paint dry, but it is only a minute and a half long.......
[youtube]http://www.youtube.com/watch?v=D32Wacc-kg0[/youtube]

For those with an interest in things technical. The servo is mounted below the signal and connects with the balance arm though a bell crank (this will be painted black)
1-IMG_7051.JPG

The servos are then connected to the output from a Picaxe 14M2 Project board. It`s not essential to have the board but as I was experimenting I thought it would be handy
1-IMG_7056.JPG

The Picaxe chip is energised by four outputs from one of those cheap receivers. This is a slightly more sophisticated version which can be modified to provide momentary, latched or self cancelling outputs on the relays. I`ve got another four on order which provide only momentary outputs but which are half the price. I wanted the more expensive version initially so I could play around with the different types of output. Many thanks to whomsoever on here who alerted us to these wonderful little gadgets.
1-IMG_7055.JPG

And here`s the transmitter. Four channels which is perfect as each of my stations has four signals (two starters and two homes) - so one keyfob per station.
1-IMG_7052.JPG

Still got a way to go - providing a power supply for each station (which will also light the LEDs in the lamps) - and figuring out how to site the signals with the servos in pits beneath which will somehow not get filled with rainwater - a bridge I`ll cross when I reach it - ho ho.

Thanks again to GregH for his Picaxe program and his help with sorting out the electronics. His program is far more realistic than some of my signals suggest - I`ve still got some tweaking to do on the linkages to show the programming off to best advantage.

Rik
 
Costings btw

Transmitter/receiver = £5.69
Picaxe 14M2 chip = £2.04
Picaxe Project Board = £3.59
4 x servos = £9.07
Bits and bobs = £0.20
Total = £20.59

Of course you could save on the Picaxe Project board as it's not essential

Rik
 
ROSS said:
a large waterproof box with accordion style bellows glands filled with grease for the actuating arm from the box might do.

SEE below for model sizes..... should be ok for the job.

http://www.ebay.co.uk/sch/i.html?_trksid=p2050601.m570.l2632.R2.TR2.TRC1.A0.H0.XRUBBER+BELLOWS&_nkw=rubber+bellows&_sacat=2562&_from=R40
Click to expand...
That's useful info - thanks Ross

Rik
 
Thanks Jon - only 15 more signals still to do...... :)
I may try some with servos above ground - to see how intrusive they are.

Rik
 
I was thinking of mounting the servo just behind the post, but above ground.

Either with the servo`s `big` side flat on the ground and then creating a false ground level across the top of the servo, which would be around rail height.
flat3.JPG


Or mounting the servo upright on it`s long edge and covering it with a small `signal cupboard` like the one in the pic. I have used that cover, made from styrene, on the same `blue` micro servo that controls my level crossing boom gate and it`s been outside for a few years now.
standing3.JPG

But I thought you were planning on taking the signals inside when not in use, so would it matter if the in-ground box filled with water?
 
Servo crossing, now I know how to do my one.

Rik, you have very kindly given costs, but where do you source the Picax and Transmitter/Reciever. from?
JonD
 
fantastic, loved the bounces.. best paint ever! :o
 
dunnyrail said:
Servo crossing, now I know how to do my one.

Rik, you have very kindly given costs, but where do you source the Picax and Transmitter/Reciever. from?
JonD
Click to expand...

Hi Jon
Picaxe etc from - http://www.picaxe.com/Hardware
Rx from - http://www.ebay.co.uk/itm/310811226450

Rik
 
gregh said:
I was thinking of mounting the servo just behind the post, but above ground.

Either with the servo's 'big' side flat on the ground and then creating a false ground level across the top of the servo, which would be around rail

Or mounting the servo upright on it's long edge and covering it with a small 'signal cupboard' like the one in the pic. I have used that cover, made from styrene, on the same 'blue' micro servo that controls my level crossing boom gate and it's been outside for a few years now.

But I thought you were planning on taking the signals inside when not in use, so would it matter if the in-ground box filled with water?
Click to expand...

Some great ideas, Greg - and also saves the extra bell crank.

Yes, I will be taking them inside when not in use, but the wiring will have to remain in situ - and I'd have to suck out the water from the pits unless I had some sort of drainage system... so I'm open to ideas

Rik
 
Forgot to mention at the start of the thread - with this approach, it costs only around 5ukp per signal to have them remotely controlled in what, thanks to Greg's programming, looks to be a quite realistic way. If you were using colour light signals then of course you wouldn't need the Picaxe or servos - the LEDs could be wired up directly to the rx.

I've just seen an 8 channel rx and tx on ebay for around 12ukp and there seems to be a 12 channel rx/tx for around 15ukp though I' not sure if it's infra red. So if you wanted to cut costs even more, you could run all manner of remotely controlled gadgets from one of these rxs. The relays on the rx can handle up to 240v and are wired separately from ach other so could handle different voltages on each circuit - though I'd not want to muck about with mains in the garden myself

Rik
 
I don’t mean to hijack Rik’s thread and all his great work, so apologies to start. But this is just my idea for A possible method mounting the servo.  It has a direct linkage from the servo arm to the signal arm to reduce ‘sloppiness’ in the linkages. (and make it easier to build – I lashed up this test in an hour and it worked first time – amazing for my lack of mechanical skills.)

In this mock-up below, the micro servo (I think it is the same as Rik is using – 11x22x22mm) is glued flat behind the mast and a piece of copper wire runs up to the arm. The distance from the servo pivot to where the wire attaches ‘A’ must be the same as the distance from the signal arm pivot to the hole in the arm where the operating wire attaches.  (ie no mechanical advantage).  (the white wires are for the signal lamp which can be powered from the servo 5V)
IMG_9840.JPG

IMG_9841.JPG

Note how I had to cut a bit of the black styrene base out to allow for the servo arm to go ‘low enough’. So maybe mount the servo on a couple mm thick styrene to raise it.

To cover the servo and protect from rain, you could cover it with any sort of ‘platform’ you like. This is a bit of plastic dampcourse that just slips on.  Note it covers the servo where the arm comes out from direct rain. I have used this method previously and it seems to be OK with these servos with plastic gears. Of course I liberally apply Vaseline around the servo arm ‘entry’.
As the servo is only 11mm high, this platform is below rail level.  For a permanent arrangement, I’d make a styrene box with sides.

IMG_9838.JPG

and here’s a short video:
[youtube]http://www.youtube.com/watch?v=gctFrYoEduk&feature=youtu.be[/youtube]

 
Elegant in its simplicity, Greg. It does more justice to your Picaxe program than my system which introduces too much opportunity for slack and sloppiness to arise in the linkages. In my next batch, I'm going to try mounting the servo at the base of the post.

Rik
 
I`ve just finished installing my first batch of four signals at Beeston Market station. The electronics are mounted in an airtight food container
1-IMG_7237.JPG

which is connected to a 12v lead acid battery to provide power for the electronics, the servos and the flickering LEDs for the signal lamps (from those cheapo tea-lights). All tucked away beneath the station.
1-IMG_7253.JPG

The servos are mounted beneath the signals and connect to the balance arm via a linkage (which unfortunately introduces some sloppiness in the system).
1-IMG_7250.JPG

However, I`m quite pleased with the effect. Only another fifteen signals to go. A parcel containing the other keyfobs and receivers arrived today from China so the incentive is there to finish the job.
[youtube]http://www.youtube.com/watch?v=QzMfeNCkgAw[/youtube]

Rik

 
Rik

Love the semaphores just to add a little something out of the box how do you keep the remote battery charged?

I have been thinking of doing a similar remote battery for my next big layout (in 5 years time when I retire and work doesn't get in the road) and trickle charging it using a solar panel like this one.

http://www.jaycar.com.au/productView.asp?ID=ZM9050

Just a thought I am putting out there.
 
The scenes in the twilight when the Railcar departed were absolutely magical ;D and yes the signals looked great too in the rest of your film
 
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