motorized wigwag

[peteski]

I also contemplated animating that signal and I agree that it will be very difficult. Something that DKS could pull off!

ArKayPee: In case you're wondering, DKS is David K. Smith, a member of this forum who has done some amazing N scale animations like working excavator, functional ceiling fan in a barber shop or animated and illuminated (in scale) barber pole sign.  He is still around but not modeling due to personal problems.

[alhoop]

This says it is N scale, so it's been done.

That's mine - built for my great-grandson. I also built the funicular shown on YouTube - he especially
likes to run it up and down. Anything to keep him interested in trains -models or otherwise.
Too much trouble to illuminate and flash the center light - I'll leave that to others.
Ps - after watching videos of working Wig-Wags , all in California, most don't have lights
flashing or otherwise. So I think I'll continue to go lightless but will probably add sound
and post a new video.
Al

[peteski]

That's mine - built for my great-grandson.
Al

Very clever Al!  Nice job!

[ArKayPee]

Hey alhoop - well done sir! A rotating fulcrum thingy, super clever. All it would take is a very slow motor rotating the shaft up thru the pole. How did you get it to always stop with the wigwag pointing to 6'oclock?

BTW, how does one give 'respect'?

[peteski]

Hey alhoop - well done sir! A rotating fulcrum thingy, super clever. All it would take is a very slow motor rotating the shaft up thru the pole. How did you get it to always stop with the wigwag pointing to 6'oclock?

BTW, how does one give 'respect'?

There are lots of gearhead motors available in various online surplus electronic shops. Here are couple examples:
http://www.goldmine-elec-products.com/products.asp?dept=1300
http://www.allelectronics.com/make-a-store/category/400400/motors/dc-gear-motors/1.html

As far as stopping in the same location, there could be a cam and a micro-switch added to the rotating shaft under the layout (and some additional logic to always stop the motor in the same location).  Or an optical sensor instead of the micro-switch.

Respect is added by up-voting the post (the small up-arrow in the right corner of the post).

[alhoop]

There are lots of gearhead motors available in various online surplus electronic shops.

As far as stopping in the same location, there could be a cam and a micro-switch added to the rotating shaft under the layout (and some additional logic to always stop the motor in the same location).  Or an optical sensor instead of the micro-switch.

The circuitry that stops the wigwag signal in the down position
consists of the nc contacts on relay RL1, diodes D5 (zener) and D6
(isolation), switch S1 and associated wiring. When the signal is no
longer activated RL1 is deenergized sending +12v that is reduced
by Diode D5 and D6 to about 2 vdc which is fed  to motor M1 causing
it to rotate in such a slow manner that switch S1 will break the
circuit stopping the motor. See notes on Fig 2. Notice in photo 8
that the set screw on the motor coupler serves as a cam that
activates S1.
PS -  sound added and IR circuitry improved - thanks peteski.
That Picaxe has a future duty - stopping a TomyTec bus at the
crossing if the wig-wag is active.

Al

[peteski]

Looks like you have it all figured out perfectly!

I assume that in addition to two current-sensing occupancy detectors the Dx and Qx are for optical occupancy sensing. But with 12V supply and 150 ohm resistor, the Dx LED will conduct around 67mA. That seems a bit high for a standard (IR?) LED.

[alhoop]

Looks like you have it all figured out perfectly!

I assume that in addition to two current-sensing occupancy detectors the Dx and Qx are for optical occupancy sensing. But with 12V supply and 150 ohm resistor, the Dx LED will conduct around 67mA. That seems a bit high for a standard (IR?) LED.

Actual current 70 ma but Peteski is right, most standard IR leds are rated at 50 ma max. TI TIL31B's are still available.
TI datasheet for the TIL31B rates it at 200ma @ 25 deg C derated linearly down to 0ma @ 150 deg C.
I'm also using two of the TIL31b's in a speed checker/axle counter (ala "TrainBoss" from BoulderCreekEngineering)
and they draw 70 ma each and dont' get warm to the touch. The TIL31b has a metal case that probably helps dissapate
the heat generated. Case temperature on the TIL31B rises 1.3 degrees F above ambient after 30 minuites of operation
wheras the temperature of a 7805 regulator driven by 12 volts rises 14 degrees F  in the same time.The 7805 is feeding just
one TIL31b and two Picaxe chips at the time. Measured with a digital infrared  thermometer that reads 94 degrees F skin temperature.

Guess I should add this:
Note: the light these LEDs emit is completely invisible to the human eye, so do not look directly into them as they can still cause eye damage, even if you can't see the light!

Thanks to all for the replies.
Al

[alhoop]

Or just DKS 

Nah, Peteski, Max and others on here could do it. Peteski could be close to DKS in miniature work.
Al

[alhoop]

Here is a 'low' wig-wag using the two in Richmond,CA as example.
Would probably be possible to power the center light.
Target needs to be about 15% larger and counter weight should
be added to lower part of actuating arm.
 I decided to go with a single high mounted Wig-Wag to protect
both highway approaches to a RR crossing.

[jmlaboda - RIP]

Here is a 'low' wig-wag using the two in Richmond,CA as example.  Would probably be possible to power the center light.

I remember seeing one of these only once in my 12 years in California... was with my Dad and really thought it was an interesting signal.  Don't know how many were actually built and used but they were an interesting Wig-wag.

I love the Showcase Miniatures Wig-wag, even if it isn't powered.  Have kicked around a few ideas but have never really looked that closely into powering one myself.  Seems like you might be able to attach the "banjo" to a rod that would run through the motor housing where it would be bent at a right angle towards the post, with a second rod being fitted with a loop placed over the first and ran down to under a layout in a narrow metal tube right behind the post to a mechanism that would rotate, with a third rod being used on it to help transfer the movement.  While some of what has been shared (detection circuits and the like are far above my head at least I have some idea of how to make it just a little better...

[peteski]

Nah, Peteski, Max and others on here could do it. Peteski could be close to DKS in miniature work.

Why thank you Al!   While I'm capable of really miniature work, DKS' work is full of clever ideas which make me think "why didn't I think of this elegant solution".  Actually that is my thought about how you animated the WigWag - very clever - I'm pretty sure that if I ever animate one of these I'll use a method based on your design.

Actual current 70 ma but Peteski is right, most standard IR leds are rated at 50 ma max. TI TIL31B's are still available.
TI datasheet for the TIL31B rates it at 200ma @ 25 deg C derated linearly down to 0ma @ 150 deg C.
I'm also using two of the TIL31b's in a speed checker/axle counter (ala "TrainBoss" from BoulderCreekEngineering)
and they draw 70 ma each and dont' get warm to the touch. The TIL31b has a metal case that probably helps dissapate
the heat generated. Case temperature on the TIL31B rises 1.3 degrees F above ambient after 30 minuites of operation
wheras the temperature of a 7805 regulator driven by 12 volts rises 14 degrees F  in the same time.The 7805 is feeding just
one TIL31b and two Picaxe chips at the time. Measured with a digital infrared  thermometer that reads 94 degrees F skin temperature.

I'm curious as to why you have to use such high-power IR LEDs for detection?  I have no problems using standard plastic-case 3mm or 5mm IR LEDs at distances of 1-2 feet.  Powered at 20mA. They have to be properly aimed at the detector of course, but that is not very difficult.

[sirenwerks]

There are lots of gearhead motors available in various online surplus electronic shops. Here are couple examples:
http://www.goldmine-elec-products.com/products.asp?dept=1300
http://www.allelectronics.com/make-a-store/category/400400/motors/dc-gear-motors/1.html

As far as stopping in the same location, there could be a cam and a micro-switch added to the rotating shaft under the layout (and some additional logic to always stop the motor in the same location).  Or an optical sensor instead of the micro-switch.

Respect is added by up-voting the post (the small up-arrow in the right corner of the post).

As much as I love this stuff, this is what I read... "Wah wah, wa wa wa, wah wah wa wa..." (Insert Charlie Brown adult sound here)

[alhoop]

..................  I have no problems using standard plastic-case 3mm or 5mm IR LEDs at distances of 1-2 feet.  Powered at 20mA. They have to be properly aimed at the detector of course, but that is not very difficult.

peteski
That is a broad statement - what do you consider detection? a low of < 0.2v?
What is your IR transistor load resistor? How is it connected common emitter -driving an opamp etc?
Bread board my circuit with just the IR diode and IR transistor and let me know at what distances you get a true low   ie <0.2 volts
at various diode currents.

Al

[bdennis]

I have seen a N scale Wig-Wag that was made by a local friend. I am going to his layout tonight so will take some video and pictures and post them.