Very inventive use of bar bell matey ... THE WHOLE PROJECT LOOKS FUN !!!
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Very inventive use of bar bell matey ... THE WHOLE PROJECT LOOKS FUN !!!
Unfortunately this weekend proved to be extremely icy here in Wakefield, and I was unable to safely leave home and walk up to Wakefield Westgate rail station, so had to give it a miss. Have to consider not breaking any bones!
Under load, i'm not sure how those ESCs will perform, or if they do perform as anticipated, how their lifespan will be. The current will only increase under load, up until they (if) they stall, where the current will be at its highest. They only way to find out realistically is to try it though. However for £8 its a bit of a cheaper loss if they do not work, or lifespan is poor.
Assuming those are the ESCs you sent me (here) - they should easily perform at full load (320A is quite a lot). Although two fully charged LiPos will be over voltage. (nearing 30V)
I do doubt that is going to get to 320A though. It's an incredibly small device with a small fan. I'm not sure how realistic the 320 amp max, that is a heck of a lot of heat in need of dissipation.
Do you recall it getting heated during off ground testing?
According to the BBC, the weather will be much milder this week. So i'm hoping that next weekend I can get there and test out these little ESCs. Even if they don't prove viable for movement, they may still be of use to help control the weapons motor, as that'll be very short bursts compared.
I have to say, it certainly has been fun getting to this point. Despite our issues and distance between myself and Colin sometimes causing issue. We've certainly used a lot of varying parts in some inventive ways. How it'll all hold up in battle, will certainly be interesting! Thankfully the majority of its structural components are fairly cheap to re-acquire for replacements!Originally Posted by katch
Last edited by Redirect Left; 22nd January 2018 at 06:14.
I was watching those on eBay too. Regarding overheating I'd take some tips from overcooking computers. I'd firstly lift the heatsink and put in some thermal compound as at that price be surprised they use any. It may be possible to replace heatsink completely with a better on or perhaps even a liquid cooled solution. Such a bargain item though. If they work I'll be getting some too, at least for my feathers.
Cheers for the advice. We'll keep you updated with our adventures with it, i'm sure.
I probably have some thermal paste lying around from last time I upgraded my PC. They're very small units, so i'm not sure how much area i have to deal with for attaching heatsinks and how effective it'd be with that small area outputting up to 320A worth of heat. If we space things about wisely internally, we might end up with a bit of excess space to play about with some oversized heatsinks. If we can figure out between us all how to make these viable units, they'd be a very cheap alternative, if they can be made to not set themselves on fire faster than Diotoirs fur at high amps, if they do to begin with..
considering fans are don't last long in combat robots i would say a liquid solution would fair even worse
Yeah. I don't think liquid cooling is in anyway a workable solution. One good hit would probably dislodge all the plumbing and spill all over every possible electric circuit knowing my luck!
Is that really 16AWG wire on those ESCs? Since it says they are for 540 motors. I doubt they will manage more than 50A.
The Fans on those small speed controllers come on as soon as they are
plugged into the battery-I'm not sure if we will put the two lipos in series
and hope it survives that voltage Adam, not after the Ragebridge blew
which was rated at 35 volt max and these are only 16 volt max-despite
us not knowing the true cause of a spark typical of touching the positive
and negative wires together of a 30 + volt battery.
What was interesting is that there was a no real spark when the lipo
was connected.
It's Sunday! Which means another day of progress, and the most surprising part. Nothing got in the way of me heading up to Colin today!
Today was spent on the electrical side of things. Colin has bought a new ESC, a Cytron MDDS60. This has a max concurrent amp rating of 60 per channel, which is still plenty for us. It also has a wider voltage tolerance, both lower and higher sides.
We firstly started by trying once more to breath life into the Ragebridge, again without success. So we quickly swapped to the Cytron and didn't waste further time with the other for now.
After a short time wiring things up, we had no luck once again, although a quick switch over of the receiever - ESC wires produced results! We've finally managed to get an ESC to fire up, and fully control the motors from the transmitter. We started on the safe side, using some old SLA batteries. The Cytron is significantly larger than the Ragebridge, so if we stick with it, we may need to juggle things around internally, but we'll find a way to fit it in there.
We then decided to move outside, when the weather finally allowed us to do so during a fairly dismal day in Yorkshire. To have a test run outdoors and with an actual floor to see how it performed.
Unfortunately we ran into a few issues here, and the robot was seemingly underpowered. So we switched the SLAs to the LiPos. Even with a single LiPo at around 15V, the robot was showing more life than the 2 SLAs at about 24V were doing. So we placed both of the LiPos in, however this is where the improvement was somewhat limited. It was struggling to move around in a meaningful manner.
We'll spend the coming week and next sunday trying to pinpoint that, if it was a matter of finding traction, not enough current, voltage, if the ESC isn't providing the needed power, or if it is a fault somewhere with the wiring or bot elsewhere. We're confident we can overcome this, and already have a few ideas for things to test and tweak over the coming week.
We also mentioned possibly using the small ESC Colin noted a few posts ago to build a feather or beetleweight with, a potential future project. Whether it'll be a new design, or just a mini version of our current build, who knows!
A few images
1) The ESC almost wired up, and just needs a final connection for a complete circuit. The wooden board here was just used to secure the ESC to, so we didn't accidentally knock it flying.
2) The bot prepped for its first outdoor adventure.
IMG_20180128_142547.jpgIMG_20180128_150057.jpg
Last edited by Redirect Left; 28th January 2018 at 18:19.
What lipo did you use was it Charged. ?
I used different receiver inputs off my dx6i to you looking at picture and the speed / response varied for me when I changed them
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