Esc Advice

[cjsowry]

All three still work, 2 for drive (running two motors each) the third for the Linear Actuator. Held in place by a zip tie and a bit of foam padding between them and the HDPE chassis. After the weekend of 8 fights they we're working loose. But suppose I should also point out, I wasn't facing any spinners or massive flippers. Manchester was more of a pushing and shoving battle. For testing and playing they will be fine. The feather rumbles at the live events, again should be fine. But serious full on combat like the UK championships.. Guess I'll find out once they publish a date!!

I use a 4s lipo (15v) and 4 cheap cordless drill motors. The rated 60amp on the box I wouldn't believe, I've read lots of stories of Chinese Amps compared to normal amps. But doubt the motor would draw anywhere near that anyway. (suppose I should really change my fuse for a smaller one, just incase. Currently have a 100amp installed. lol. That's another way to ensure its a tad more protected, use a fuse whos amps are lower than the esc's rated MAX.....

The only problems I had was my driving into the pit, (again not helped by the bot turning during acceleration and braking occasionally), The bottom hinge of my actuator bending and sticking out the bottom of the chassis lifting my wheels off the ground and a receiver plug falling out.

Asking for advise, you're in the best place, I was where you are 6-9 months ago. But there comes a stage you just need to take the plunge, buy and test it. I'm doing the same with my heavy at the moment. Constantly online checking specs of components and looking inside everyone's bot, to see what they do, what works. I need to place that damn order and just connect everything up, but worried I'm wasting 100's of pounds. Why starting with feathers is much more wallet friendly, mistakes only cost 10's of pounds......

[cjsowry]

Several points during this video, you can see the bot turn slightly to the right after I let go of the stick. I don't know why, I'm guessing its the esc's, on the spec sheets it mentions the resistance is higher when in reverse. Always one of the motors/esc is in reverse when traveling in a straight line!! perhaps someone with more knowledge could explain!!?

https://www.youtube.com/watch?v=vTqx...LrywRk&index=8

[Runsler]

The thing as well for the ESCs from Rory as the IBF ones is, both can also do repairs on them.
And... well, the IBF one at least got a fuse itself, so to actually damage it, you'd need physical damage to it.
Place it somewhere nice and safe in the bot with some shock mounting, and that should do the trick.
Most bots i've seen became unmaneuverable due to loss of wheels and such way before anything ever came close to the expensive electronic parts. sometimes switch out a motor or gearbox, but that's it.

[Shakey]

Several points during this video, you can see the bot turn slightly to the right after I let go of the stick. I don't know why, I'm guessing its the esc's, on the spec sheets it mentions the resistance is higher when in reverse. Always one of the motors/esc is in reverse when traveling in a straight line!! perhaps someone with more knowledge could explain!!?

To me it just looks like a trimming issue causing one side not to go into brake. Make sure to do a full trim:

Apologise in advance this may be a tad patronising, I just copied it from my custom antweight care sheets.

"Your robot should be controlled but it may not be quite right, the wheels may try and turn on their own or the flipper may not go all the way down. These are fixed with trims, they simply nudge where the middle position of the joystick. Your trim controls are the buttons immediately to the side and below the joysticks. If your robot is trying to steer left or right simply press the trim button in the opposite direction on your steering stick until it doesn’t, the same applies to the forwards and backwards. The easiest way to do this is to position the robot the right way up but with all wheels lifted off the ground, when you push forwards on the stick all wheels should start at the same time. If they do not make a note of which way the robot would be turning and click the trim in the opposite direction. Keep repeating until all the wheels begin turning at the same time. Now use the steering stick to turn the robot, again both wheels should begin turning at the same time. If they do not not if the wheel that is moving first is going forwards or backwards, click the trim for forwards and backwards in the opposite direction. Keep repeating until all the wheels begin turning at the same time. "

The resistance things *shouldn't* be the cause, that'd manifest as one side of the ESC becoming hotter. Unless the have a firmware difference in how they brake from forwards or reverse, but that'd be an odd thing to do.

Normally mechanically uneven drive is more a concern with bias timed motors like dewalts. Where one running backwards gets much hotter than the other, never noticed a power difference in my dewalt bot though.

[maddox10]

The el cheapo ESC's from Ebay (the Blue's), have a limited reverse, like 50%, and also do have a brake bias depending change of direction.

Those combined with small differences in timing (even center timed) on the equaly inexpensive motors used in batterydrills will give an noticable inbalance in drive.

One of the reasons some of the machines use a gyro, and the main reason why team RCC prefers RW specific controlers like the Scorpion XXL mk1 or IBF 4.X

Those can be trimmed, adjusted and pampered to an extend even modern RX/TX sets can't do with single drive ESC's ,even with extensive reprogramming.

[Theo]

Like I said, I'm going to get 2 dual 'blues' for testing, then a Feather2 both when I find out they can run 4 motors and les not completely busy

[maddox10]

We smoked more of the Blues in 2004-6 than I care for. Gets stale fast, those smokebombs.

That stopped once we went Scorpion XXL Iliama version.