Alternatives to MC29

Working on lights decoration for worlds robot and I need to strictly follow the non-functional decoration rules. I had been using a trio of MC29s to control my lights, but this won’t pass worlds inspection due to a certain foolish Q&A answer.

Does anyone know where I might find a (not too expensive) alternative to an MC29 that is not made by VEX?

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Ok, classic XY problem here. https://xyproblem.info Tell us what you want to do, let us help you craft a solution.

Also tell us more on why the 29 controllers cant be used on a decoration.

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I’ve used plenty of motor drivers from here, look for servo control or something that takes RC pwm input.

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No Foster, this isn’t an XY situation. I know exactly what I need, I just don’t know where to find it.

This is my method for powering the lights. An Mc29 works, I just need one that isn’t made by VEX.

Read here

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My robots lights are not connected to the robot at all, instead they are connected to a small battery. Unfortunately I cant control them mid match but it is what it is

I’m looking there, I’m not sure exactly what the controllers look like/what kind I need. Much of the electronics here look unknown to me.

And I need mid-match control for reasons, hence why I asked for help in this thread.

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I’m pretty sure the v5 port is a regular telephone cord right? You might be able to get or make an adapter with that to work with the lights. I doubt something like that already exists so it would require some DIY work.

Or rather, since you’re trying to utilize a motor controller, while I’m not certain on what the internals of a vex motor controller is like, I know it’s a pwm controller so maybe a generic pwm controller of of amazon like this https://www.amazon.com/WayinTop-Voltage-Controller-Adjustable-Control/dp/B08BJ4WQCV/ref=mp_s_a_1_8?crid=1KIQPPRTIZYA5&keywords=pwm+motor+controller&qid=1647811312&sprefix=pwm+motor+controller%2Caps%2C152&sr=8-8 might suit your purpose?
Or I found an arduino based one this could also work https://www.amazon.com/High-Power-Transistor-Driving-Controller-Electronic/dp/B07XJSRY6B/ref=mp_s_a_1_3?crid=1YRP7XD408AIR&keywords=pwm+motor+controller+arduino&qid=1647811482&sprefix=pwm+motor+conteoller+ardu%2Caps%2C236&sr=8-3

Another option that could work would be using SK9822 or APA102C LED strips instead. They could directly interface with the V5 and only need two three-wire ports to work. They are individually addressable and just take 5 volts, ground, clock, and signal. They have a separate clock line (unlike the WS2812B strips) which means they can work with the limited update speed of the VEX three-wire ports. Obviously they are harder to program, but there should be an Arduino C library that with some small tweaks could work on V5.

But if you want to stick with the lights you have, these guys should be a drop in replacement for the MC29 for this application (not sure how the MC29 handles reverse since I never used the cortex, but if the V5 just outputs a PWM signal these will do the trick quite nicely)

(Edit: missed that @Colin2114R posted another listing for these above, although the controller with the knob he posted will not work without some hacking)

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I like these adafruit boards (they make a range of them) Adafruit DRV8833 DC/Stepper Motor Driver Breakout Board : ID 3297 : $4.95 : Adafruit Industries, Unique & fun DIY electronics and kits

They are out of stock with them, but Digikey has them https://www.digikey.com/en/products/detail/adafruit-industries-llc/3297/6419360 for the same price.

Pretty easy to use and they will let you push 1.5 amps to the lights.

Turns out this is actually harder to do at reasonable cost than I had anticipated.
First, hobby RC pwm that comes out of the 3-wire port is not the same as the pwm that some of the drivers linked in previous posts need. Be careful with anything that says pwm input and check what it actually means.

If all you need is on/off control, this may work.

I’m not finding a good MC-29 alternative that costs < $50, I’m sure they exist somewhere, just not as easy to find as I thought they would be.

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:sob: the perfect electronics already exist and I have a ton of them but they’re just illegal for no reason. why gdc why. I am pretty sure they misunderstood the question that was asked in that q&a too.

I would have half a mind to just show up with my mc29 array and argue with the inspectors about it.

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I’d do it, odds are they aren’t staring at the qna for hours a day and probably won’t bat an eye. The worst I got from worlds inspectors was that the light strip’s remote control would interfere with match play.

No remote control, the whole point of the mc29 array is to control everything from the brain itself.

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There is some stuff on Amazon, reviews are not good for any of them, I’m not even going to recommend one as I’m not sure you really want to connect these to your $350 V5 without testing them externally first. search on “rc hobby brushed motor driver”

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Ya the closest I found was on this random site and didn’t even look for reviews. The MC29 is actually like the best on the market.

https://www.micronwings.com/Products/ESCBrushedMicro1-2S2A/index.shtml

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yea, that’s similar to the Amazon products.
The problem with all these is no detailed information is given, so when I read things like.

Note that this ESC does not include a BEC so the voltage of the battery is supplied to the receiver.

I would need to understand far more about them before hooking up to a V5, it may just mean battery pos and gnd are directly connected to the receiver pos and gnd wires, but who knows, that’s why It needs evaluation standalone before using it.

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Just cut the casings off of them. No one will know :wink:

In all seriousness, the strips bob132 posted may be your best bet.

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If I modify a VEX V5 motor, wouldn’t that mean it’s no longer a VEX V5 motor legally? Technically speaking though, if you mod the MC29 and solder like a light onto it, would that mean it’s no longer a VEX MC29?

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It should, yes, and if you read my response to the Q&A that I posted, that is one of the things that I argue.

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