Simulated Brake Spark

The guy just sent the video link. Takes a minute to load and the page is in Chinese unless you change the language at the top right of the page.

Looks pretty good! 

https://www.bilibili.com/s/video/BV1As411u7xh

We prewar Lionel operators have lot of sparks already!

I simulated it just yesterday when I put a passenger car on incorrectly!  (please excuse the bad - and obvious -  joke!)

Actually- with all that the mfgs. HAVE already as far as features- what is left??  Brake spark might be in our future.

Generating the brake spark can be as simple and inexpensive as a flickering LED... for example from an LED candle you get at DollarTree for, uhh, $1.  Or there are many pre-built flickering/random blinking circuits used in modeling to simulate campfires, welding, etc.

More interesting is knowing WHEN to trigger or turn on the sparking.  In the example you give, the engine's electronics KNOWS WHEN it is slowing down and hence KNOWS WHEN to turn on the lighting effect.  If attempting to add this effect after-the-fact, I'd be surprised to find any engine electronics that has an output or trigger signal indicating when the engine is braking or rapidly decelerating.  For example, I know that in MTH PS2/3 you can get a brake squeal sound when rapidly decelerating....but I'm fairly certain this event is not available as an electrical trigger signal that can turn on a flickering/sparking LED circuit.

In which case I'd think you need to concoct a method to detect rapid deceleration by somehow monitoring the speed of the engine.  There are many ways to detect deceleration which can be elaborated upon if there's interest.

Simplest way I know of would probably be to do something with motor voltage.

worked on the railroad for years, never saw a brake spark. maybe something you saw in the movies. 

Rick- Most videos on YouTube are showing brakes sparking from slipping, not braking, but there are a few. I appreciate your comment from real world experience. Nothing from a movie, I just like pushing the envelope on what we can do. Spark from a pantograph and 3rd rail is in the works on my RR, so when I saw the model for sale on eBay with brake spark it got my interest.

John- that's exactly what I was thinking, something simple (or as simple as possible

Stan, I am not there yet, but wanted to see the crowds reaction and if somebody had already done it. John is on the same track as me, to keep it simple, but you bring up the crucial point as to how to trigger it. Any deeper thoughts are certainly appreciated if/when you have time. It's a project I will be looking at after the 3 or 4 right in front of me are done I have seen a handful of guys do spark/arcing from 3rd rail subways and pantographs and that is in the works currently on my RR. I have personally only seen 1 attempt at brake spark, that's why I posted. Thanks.

Wheels brake locked, sparking on the rail is a no-no too; flat spots.

How about a nice hotbox? There are cars that simulate a hotbox bearing.

Sounds andoand smoke too 

Warning: this will fast become the most annoying thing you own. About once or twice a year I fire mine up for the smoke feature; sound off.

You can find "hotbox refers", etc. on Youtube and a few old threads to see what it's all about.

@Adriatic posted:

Warning: this will fast become the most annoying thing you own. About once or twice a year I fire mine up for the smoke feature; sound off.

You can find "hotbox refers", etc. on Youtube and a few old threads to see what it's all about.

I have two of those, and one of my first mods was to add TMCC control.  That allows me to run around and randomly trigger it ones in a while for amusement, but not have it constantly triggering.  I'm going to expand the controls one of these days and add a relay to enable/disable sound by command control as well.  Since I used the ERR Mini-Commander ACC, I have extra outputs, so it's a simple addition.

I put EER Mini-Commander ACC in my Hotbox Reefers as well. I also added a small LED that sticks out a bit just under the frame that turns on when the Reefer live so I know when it is gonna squawk...or not.

I thought it might work better with a 15m to 3hr random choice timer board. "Maybe you get a hotbox or two; maybe not." 

@jockey31 posted:

..

Stan, I am not there yet, but wanted to see the crowds reaction and if somebody had already done it. John is on the same track as me, to keep it simple, but you bring up the crucial point as to how to trigger it. Any deeper thoughts are certainly appreciated if/when you have time. It's a project I will be looking at after the 3 or 4 right in front of me are done I have seen a handful of guys do spark/arcing from 3rd rail subways and pantographs and that is in the works currently on my RR. I have personally only seen 1 attempt at brake spark, that's why I posted. Thanks.

As you say the crucial point is how to trigger it.  I find it odd that even though the engine in your video has "access" to the trigger (e.g., the brake squealing sound), the sparking continues after the train/squeal stops.   Seems they could have done better.  Also, if going through the effort, it's odd they did not randomize the sparking of the 4 brakes - they all spark in unison which detracts from the effect - in my opinion of course; yes, 4 independent LEDs means 4 independent circuits but they did seem to do a nice job with some of the other lighting effects.

Motor voltage can be a simple source of a trigger but can be problematic.  For example, it's not the applied motor voltage from the electronics that you want to measure; it's the back-emf or motor generator voltage which is a far superior indicator of motor speed.  But I'm getting ahead of myself!  When you get closer to actually experimenting with the idea, I'll be interested in continuing the dialog.

Separately, I seem to recall an OGR thread where the idea was to detect when a train is going around a curve...I think for the purpose of triggering flange squeal sound(?).  IIRC when you do the math, it might be possible to use inexpensive solid-state accelerometers to detect change in direction.  That is, an accelerometer or similar inertial sensor could also detect rapid deceleration.

Unless you're providing the motor control, I think measuring the back-EMF may be somewhat difficult, you have to time it for when the motor is not getting drive voltage.  FWIW, while the motor voltage is not an iron-clad indicator, it's a ton easier to use.  Also, if the locomotive has cruise, voltage on the motor will certainly indicate it's moving.  It really depends on the actual locomotive you're trying to add the feature to.

I agree with Stan, the four locations should be independent and random.

As for curves, the Lionel Legacy Vision Line Tank Cars from 2009 had an angle sensor to change the sounds on curves, it was a simple arrangement.  It had a hanging pendulum that swung out on curves and a sensor board under it that triggered the sound board to recognize the curves. It works great on the tank cars, I love the effect and the reaction to curves, really adds a dimension to the sound generation.

Here's some of the pieces used in the tank car.

It comes down to defining "simple".  Agreed measuring back-emf is more complicated than simply measuring applied motor voltage.  But like many things in life you get what you pay for.  And of course the objective is to detect deceleration...not  speed.  I suggest waiting until the OP gets closer to implementation when we can hear exactly the configuration, command vs. conventional, whether soldering and component-level assembly is on/off the table, Arduino on/off the table, and so on.

As for the hanging pendulum inertial sensor, this would be like those cattle cars that would trigger the cow or chicken sounds upon movement... IIRC, QSI came up with this sometime in the last century.

Clearly this would be a simple and inexpensive method to detect deceleration.  The trick would be to only detect deceleration and not acceleration.  In a cattle car trigger one expects sounds upon starting or stopping.  Likewise, if used for curve detection it doesn't matter if "turning" left or right.  So it would take some thought to "tune" the pendulum mechanism or insert an electrical filter circuit to only generate a trigger when it swings in one direction so to speak.  That's the advantage of chip accelerometers as the polarity of the voltage output indicates both the sign and magnitude so that acceleration can be ignored.

You guys are awesome! I love the enthusiasm about new ideas. I am a ways off from implementation, clearly, but the ideas are great.

To answer the posed questions;

-Control is DCS

-Soldering Yes

-Arduino (would need help)

Have a great Saturday!

Well, with DCS I don't see how back-EMF is going to work out, I'll let someone else try to get that working.  If you're measuring motor voltage, you could logically wait to trigger for the voltage to start decreasing and then trigger the effect.

I'd run the motor voltage detection using an isolated power module and power the whole system within that framework.  Probably an A/D input on that Arduino would be the ticket to detect when you were decelerating.

What triggers brake/flange squeal on my TMCC E-33 or railsounds Berk Jr tender?  

Could a sound frequency be a trigger with the aid of filtering so every sound doesn't trigger it.  (I know it could, I'm curious if a Chinese board might exist already. Like the old music detection "dancing" mood lights, with colored lights triggered by various frequencies and volume level changes varying color& intensity.)

( 🤔..RIP Dale M. 🤧)

@Adriatic posted:

What triggers brake/flange squeal on my TMCC E-33 or railsounds Berk Jr tender? 

The R2LC serial data comes over and the RS board decodes if you're braking based in the serial data stream.

@Adriatic posted:

Could a sound frequency be a trigger with the aid of filtering so every sound doesn't trigger it.

Could it?  Maybe.  However, that filter would likely change for each type of horn and/or whistle.  Also, I have serious reservations about how reliable that triggering would be.

I heard a duck and aimed "up"