Screen goes off when car passes on dead strip

Slingshotx said:

Do you mean the whole monitor display goes black. I.e. no RC no operating system? Or does RC crash?

Can you expand on wiring? How is dead strip wired? Via Arduino or direct to pc? How have you protected pc from deadstrip? Does it only happen when a car is going fast?

From your description sounds like car generating back EMF is causing a spike somewhere. Does moving screen/pc help?

Click to expand...

Thank you for answering, the screen turn off for a second and then it come back by its own, RC does not crashes neither the PC, it continues to work.

My RC setup is via arduino and it's wired directly to the dead strip, positive enters directly to the relay and negative enters to the Arduino GND pin, there is nothing between the death strip and the relay modules because I assumed it had it's own EMF protection.


The PC is conected by a 15 meter cable over the top of the track so it is not near the
I didn't find any pattern but it happens more with anglewinder cars or car with magnet.



I'll check meanwhile with the suprresion signal ring.

Swapping out the arduino with TM may or may not fix your issue. And it's probably going to be expensive to do. If it comes to that, I'd suggest talking to Viasue (full disclosure they're my partner). He offers a dead strip solution that is arduino based. If you do that you might want to bring me into the loop. If it turns out it is the arduino, then obviously his product wouldn't work either and the two of you would have to work out a refund model which would be very unusual for him. Does TM offer a dead strip solution? What if you buy TM and have the same issues?

But before any of that I'd try troubleshooting in small steps. If you can prove its the relay that would go a long way. Try removing input power to the relay. Did that fix it? Put it back and try removing just output power. Obviously lap counting won't work, but did it fix the TV?

If it's the relay, you can buy a relay like the one TM provides and see if that fixes you. If it does great, if it doesn't then buying TM won't solve your problem and you'll be out a bunch of money.

If going small doesn't figure it out, I'd replace just the dead strip as the next small step. I've never heard of using a relay like this (very cool by the way), and there are other ways to do the same thing without a relay.

I'm not very good with interfaces so maybe everything I've said here should be ignored. But that's my two cents.
-Dave

Race Coordinator said:

Swapping out the arduino with TM may or may not fix your issue. And it's probably going to be expensive to do. If it comes to that, I'd suggest talking to Viasue (full disclosure they're my partner). He offers a dead strip solution that is arduino based. If you do that you might want to bring me into the loop. If it turns out it is the arduino, then obviously his product wouldn't work either and the two of you would have to work out a refund model which would be very unusual for him. Does TM offer a dead strip solution? What if you buy TM and have the same issues?

But before any of that I'd try troubleshooting in small steps. If you can prove its the relay that would go a long way. Try removing input power to the relay. Did that fix it? Put it back and try removing just output power. Obviously lap counting won't work, but did it fix the TV?

If it's the relay, you can buy a relay like the one TM provides and see if that fixes you. If it does great, if it doesn't then buying TM won't solve your problem and you'll be out a bunch of money.

If going small doesn't figure it out, I'd replace just the dead strip as the next small step. I've never heard of using a relay like this (very cool by the way), and there are other ways to do the same thing without a relay.

I'm not very good with interfaces so maybe everything I've said here should be ignored. But that's my two cents.
-Dave

Click to expand...

Indeed, I agree with Dave, the idea is that I constantly update and try new things with Arduino and RC, that's what I love about this.

Yesterday my partner brought his laptop and it seems that the problem stopped as far as we saw. I'm starting to believe it's my computers problem, that it's too sensible to this kind of interference because I installed the capacitors like the ones in the Scalextric cars and it just helped a little bit, but it's hard to tell. I installed them at the output and input of the relay board to the arduino. But when I changed the computer it aparently stopped. I was using a mini pc:


I'll do more testing today, we had a big race and we preffered to run with a blinking tv rather than a RC unconfigured version where we were having issues with the arduino driver, so now that I got more time I'll check and tell everyone what happened.

I believe this problem could also be solved if I used solid state relays to avoid this interference from having 2 four channel normal relays boards clicking at the same time:

Also thank you to RichD, the text was a very helpful.

The suggestion I made of the capacitor across the coil might possibly have been a bad one, if the capacitance is of a particular value it could make it worse (as it could form a tuned circuit) but if you have tried it and it helps then leave it there. But snubbing the noise to ground should help a lot. Good practice is to use a snubbing diode but it looks like this may already be present (as it should be) 0.1uf caps to ground from the noisy point in the circuit is common practice in general but I haven’t seen it with relays but could be worth trying. I would have to investigate your circuit further to offer anything more but you could do some reading about snubber circuits regarding relays and switching or just use SSR as you have just mentioned.

I am not sure of the impedance specs of whatever video transmission standard you are using but sounds like the laptop you tried has either a better video output card or just different specs that suit the application better. This is why I suggested a VGA amplifier if you have one (that is best practice if driving VGA over a longer distance, commonly called a VGA video repeater) DVI-A, DVI-D, HDMI, displayport etc probably have different performance characteristics when running longer cables which is why I suggested changing video standards if you have the bits lying around. Different cables will have different performance characteristics, you may find a better quality cable will also help. Or a different video output card as you have already found. Just trying to give you the full picture so to speak. In my line of work we commonly use various methods to send the video signals over Cat5 or Cat6 cable over long distances but this introduces new problems which is why I haven't suggested that type of method.