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Messages - zacodonnell

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Progress Reports / Re: Team Brain Damage
« on: January 06, 2019, 09:16:18 pm »
Thanks to the suggestions here I'm looking at brushless rage (the smaller one) which has ratings very close to the ones on my motor. It fits well into the bot too. The other option is something like the Castle Edge HV120 which leaves a ton of headroom over what my system would produce and still fits in the bot. I like the castle for the data logging and I've been very happy with the ICE 100 I'm using in both bots for years. I'm thinking In-fight reversing may be more trouble than it's worth but I'll have to keep thinking about it. I still have a couple weeks until I have to commit, and I can run 8S with what I have on hand for initial testing.


Progress Reports / Re: Team Brain Damage
« on: January 05, 2019, 06:51:57 pm »
Actually, I think the VESC is what 60 Seconds of Glory was running last year. I know they did melt it down in one of the fights but that might not have been the controllers fault. Pete, care to chime in on what happened and how your experience with the VESC has been? Where did you get yours? It looks like there are quite a few "VESC Compatible" models out there but some look pretty shady.

The reversibility is the difference between this fight in which all of the teeth were broken off of the shell and I took major damage:

And this fight in which the two weapons meshed with each other and I was at a huge advantage the whole time:

With a shell spinner I don't have a weak side, but the teeth are not as strong as the teeth on a solid bar spinner. By making the two weapons mesh, I reduce the forces in the weapon-to-weapon impacts, which allows there to be more weapon-to-frame impacts. Since my shell is all weapon, the only weapon-to-frame impacts are the opponent's frame. This is a good thing for me. It is so lopsided in fact that Andrew added a reversible controller to Glasgow Kiss so he could avoid it in the future.

The reversibility is only required against a horizontal spinner that could run in either direction like GK. Many are unidirectional, with a tooth that is raked in a specific direction or a steel tip on only one side of an aluminum bar.  Because of this my plan is to run a high-power airplane ESC most of the time, and drop to a reversible 7S ESC for fights like GK... at least that's my current plan. Otherwise I have to decide before the fight and hope I guess right. The angled shell was much better against a solid horizontal than the cylinder is, so I need to offset that disadvantage somehow.

I reworked my aluminum drawing this weekend and I'm spending more time on the 3D design part to make sure it's right before getting excited and ordering another run of parts. So far I've caught a few mistakes so it has been useful, but it is time consuming. All part of the fun though. Tomorrow I should wrap up the 3D part and hopefully start working on the weapon roller assembly and drive wheel hubs. If I have more time than I expect I might work on a wiring harness to see how the drive motors work, but we'll see.


Progress Reports / Re: Team Brain Damage
« on: December 31, 2018, 07:00:49 pm »
Thanks for the info. I'd never heard of MGM motor controllers before. It looks like they do have something that fits physically and electrically. They have a lot of data on their controllers on the site too, and it looks like it even comes stock with forward/stop/reverse set up on it. The only downside is the hefty price tag. I'll have to decide if the feature is worth it. I may just run 7S reversible to start, and once I get the other issues worked out look into pushing it to 10S unidirectional except when it matters.

I hit a snag working in the shop today. The steel ring I'm using for the bearing inner race is too hard for even my carbide inserts to do anything meaningful to. That means I need to rework the bolt holes in the center post to avoid the thicker wall of the steel ring. That has me eyeballing another run of .125" aluminum parts with several small design improvements I've identified as I'm putting the thing together. The darn shop just makes it so *easy* to re-run the parts... This and a few other small things make me want to spend a little more time on the design on the compter before commiting to fab work. I normally would, but wanted to use my time off wisely.


Progress Reports / Re: Team Brain Damage
« on: December 31, 2018, 11:13:30 am »
Lots more progress yesterday. I got all the drive motors and controllers finished and added glue to them as strain relief. I also finished all the drive pods. Today I'll be working on the weapon center post

Pictures: (whole album, it doesn't let me link to a specific starting point. Check out about half way down)


Progress Reports / Re: Team Brain Damage
« on: December 29, 2018, 10:30:04 pm »
Ok, as promised here's the beginning of the build report for Hyperpolarized for Moto 2019. I switched to imgur because Picasa was abandoned by Google. We'll see how it works. So far I think the Imgur UI is buggy and mediocre, but it works ok for now.

I've probably got 15 hours into the assembly work at this point. I don't have anything else really planned for the next three days either, so here's hoping I can keep making progress. My weapon belts won't be here until after the holiday because I ordered the wrong ones initially and SDP-SI is off until 1/2. I should be able to get everything assembled and wired up before then. The shell fab starts after the holiday too.

If anybody knows of a reversible ~10S x ~100-120A controller I'd love to hear about it. I have a 4 x 1.75 x 1.625" space to fit it in, longer if it is less wide.

Comments welcome:


Progress Reports / Re: Team Brain Damage
« on: December 24, 2018, 05:19:34 pm »
McMaster order went in today. I ordered the wrong belts and pulleys initially so Iím swapping for the right size.

I also rushed the laser drawing through before the holidays so I missed a part Iíll have to remake. Ah well the other parts look ok so far. Iíll be working on them in earnest on Wednesday

Glad to hear there are a couple people following along. Iím hoping to do regular ish build reports again. I sure hope it works!

Progress Reports / Re: Team Brain Damage
« on: December 21, 2018, 12:34:55 pm »
Yes, it will likely reduce the flipping power somewhat. The redesign I have in mind should improve flipping power and stability significantly but alas, only so many hours in a month :)

A CVT would be cool, but seriously, this bot doesn't need *more* complexity. It's hard enough keeping it working as is


Progress Reports / Re: Team Brain Damage
« on: December 20, 2018, 10:44:23 pm »
I got myself a SpaceMouse for Christmas, which I just installed tonight. It's going to take some geting used to but I can already tell it will make working with my 3D models a completely different thing. The 3DConnexion space mouse works fine with my version of Alibre Design out of the box, though I did have to turn down the sensitivity because I'm too clumsy for the default.


Progress Reports / Re: Team Brain Damage
« on: December 20, 2018, 09:59:53 pm »
Thanks to a timely reminder from one of the folks on here I made it into Motorama registration with both a 30 and a sportsman bot. The sportsman is likely to be the same one I brought to Franklin with very few changes. I may reduce the gear ratio so it spins up a bit faster but that's probably it. I have a total redesign in the concept phase but won't have time to implement it for sure.

My time is instead going to be focused on the 30 pounder, which is yet another shell spinner. I believe this is the 7th generation of shell spinner and I'm hoping it will combine the best parts of the last couple. I'm trying some new stuff, and there are some spots that are maybe a little questionable. i don't expect it to do amazingly well at the first show, but I'm hoping to work some of the kinks out and smash some stuff in the process. Parts started arriving yesterday so it's getting real.

I was going to get the base cut out of 7075 by big blue saw but I procrastinated too long on getting the drawings done and now they're all backed up from you guys. I ended up falling back to the local shop and just lletting them use the 6061 they had on hand. They're a lot less busy this time of year than BBS, so they turned it around in two days and shipped it today. I hope it will be strong enough.

More details on the design will come along as I work through the final parts and the build. I hope to have a little time between Christmas and New Years with little else on the agenda. There are a lot of bots registered for Motorama, and I'm afraid of quite a few. Big Ripto isn't registered which is good since he's retired the last two shells... at least I might make it through one show without taking that hit. The other vertical bots are scary too of course, but the history isn't quite there.

Happy building!

Progress Reports / Re: Team Brain Damage
« on: November 12, 2018, 11:34:18 am »
Yeah, I'll be there. Not sure yet if I'll be able to register both, but I'm planning to bring Magneato and hopefully a full combat 30. The design stuff is already in the works on the latter and fabrication will likely start a little after Thanksgiving. Looking forward to seeing everybody.


Progress Reports / Re: Mutually Assured Destruction
« on: November 04, 2018, 06:26:17 pm »
You know, you might be right. I left a message in his thead here. If you want to ping him on Facebook he can contact me through here.


Progress Reports / Re: Team Ignition
« on: November 04, 2018, 06:25:21 pm »
Did you leave a dark grey Quebec hoodie at Franklin this year? I picked one up near my table and was thinking it might be yours. I can bring it to Moto or if you need it before then I can ship it.


Progress Reports / Re: Team Brain Damage
« on: November 03, 2018, 06:15:39 am »
Here is the build album for Magneato before FI 2018. Not quite as much as a fresh build but still some interesting stuff in there.


Progress Reports / Re: Mutually Assured Destruction
« on: November 02, 2018, 09:21:43 pm »
I think you might have left your sweatshirt at the pit table. It's dark gray with a white logo on the front. Did you lose one?

I can bring it to Moto if you want

Progress Reports / Re: Team Brain Damage
« on: November 02, 2018, 09:20:38 pm »
Ok, maybe I have time after all...

Magneato had a pretty mediocre showing record-wise at Franklin, despite getting a few upgrades before the show. I added an outboard support bearing to the weapon shaft to stop the flywheel from skipping off of the baseplate, and replaced the weapon shaft itself that had become pretty bent over the last few years. I also replaced the rear shaft and the baseplate from the giant gash that Pitter Patter put in it at Moto.

The bot still gets stuck upside down way too easily, takes too long to power up between flips, and has issues with gyroscopic precession (see #1). I was more careful with the drive system this time to avoid flipping myself over, but of course it happens in every fight.  I also had some flakiness with the weapon throttle for some reason. I'm starting to think I have a bad connection on the weapon ESC signal wire somewhere. That happens to also be the 5v supply for the rest of the bot, so it is actually a single point of failure for the entire weapon system. I should probably fix that.

I did manage to beat Clomp this year, which is great because they are a team I mentored a little bit and they put me out of the tournament two years back. I needed some payback. Now we're 1-1 so I guess next year will be the rubber match.

I'm uploading some videos now:

I think the most fun I had was the Sportsman rumble. Ed, Jim, Kathy, Beth (and the gang) managed to jam time in for it right at the end of the show despite some pretty heavy pressure from the FI folks. It was super fun and chaotic... everything we thought it could be. All I can say is.... TO THE DOOOORR!


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