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Author Topic: Team Balhogs: A Maiming  (Read 961 times)

samhanson

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Team Balhogs: A Maiming
« on: December 23, 2016, 10:44:36 am »

Greetings all! The following is a design, build, and competition report for A Maiming, a 30lb Sportsman built by Team Balhogs for Motorama 2017. Our most successful builds have been accompanied by progress reports, some of which you can find on the delphi forums going back as far as 2004. Progress for A Maiming can be followed on instagram in an abridged form: @balhogs https://www.instagram.com/balhogs/

A Maiming is designed as a saw under cutter. The intent is to use a powerful circular saw to target wheels and disable the opponent through impaired mobility...

Here is the weapon by the numbers:
Weapon: 14" diamater 36 tooth
Weapon Motor: 5065 size 380kv brushless outrunner
Weapon Gearing: 2.6:1 via #35 chain
Weapon Battery: 8s 60c 2000mah

The drive looks like this:
Wheels: 5" Colsons
Drive Motors: 16:1 p60s with 550 size motors
Drive Gearing: 2:1 via #35 chain
Drive Battery: 4s 60c 2000mah

The chassis is as follows:
Armor: 13ply (.71") baltic birch plywood
Attachments: Large nutstrip with 1/4-20 bolts
Top Armor: .09" titanium
Handle: black rubber



The design process involves CADing and SpreadSheeting at the same time. The CAD work is performed on a pirated copy of autocad and is eventually used for plotting holes and to rout out the frame pieces on a cnc router. The spreadsheet is made through google sheets and can be viewed  here: http://bit.ly/2ikwlTK

look at that handle!

A Significant number of components for A Maiming are sourced from our previous 30lb Sportsman, Piston Wax (http://imgur.com/a/SsNrF). Including the drive motors and gearboxes, the v1 ragebridge, and all the nutstrip and bolts. That scavenging allows for some savings on the overall cost of the bot, but it is projected to be around $500 which in all likeliness will put the grand total closer to $1,000. We're very excited to be a part of the Largest Motorama yet and excited for the future of robot combat in general. Stay tuned for updates as we takes steps forwards and backwards towards our goal of 100% wheelectomy rate.



Team whanton2

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Re: Team Balhogs: A Maiming
« Reply #1 on: December 23, 2016, 04:29:28 pm »
I believe your weapon rpm might put it in the feather weight category?

samhanson

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Re: Team Balhogs: A Maiming
« Reply #2 on: December 24, 2016, 01:15:58 pm »
I believe your weapon rpm might put it in the feather weight category?

I referenced these particular rules:

4.2.3.1.
Specific weapons of very low mass or very low moment of inertia
(MOI) may be allowed at a higher rpm. Th
e intent of said weapons
should NOT be to deliver large kinetic hits. But rather cutting,
drilling, scraping, ect.
4.2.3.2.
All weapons operating above the 400 rpm limit MUST be submitted
to the event organizer for approval during the registration period.

And got approval from NERC dudes a couple weeks ago.

Badnik96

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Re: Team Balhogs: A Maiming
« Reply #3 on: December 24, 2016, 11:25:45 pm »
I love the handle idea. Certainly makes it easy to carry!
TEAM IGNITION
FireArrow (Antweight) 23-11
Nocturne (Beetleweight) 5-10 (Retired)
KnightShade (Beetleweight) 0-0
Landshark (Mantis) 1-2

Pennbots 2014 and Bot Blast 2014 antweight champion. Bot Blast 2013 Best Driver and antweight third place.

daggius

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Re: Team Balhogs: A Maiming
« Reply #4 on: December 27, 2016, 01:32:48 pm »
handle is the best part lol

samhanson

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Re: Team Balhogs: A Maiming
« Reply #5 on: December 28, 2016, 07:24:40 pm »

The saw arrived via ebay. Pretty pleased.

14" diameter
1" arbor
36 tooth
Henry Diston

zacodonnell

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Re: Team Balhogs: A Maiming
« Reply #6 on: December 28, 2016, 09:34:35 pm »
Hmmm... Maybe my giant exposed wheels plan isn't as smart as I thought...

Glad to see you guys coming back for more and I look forward to another nice, detailed build report

-Zac

zacodonnell

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Re: Team Balhogs: A Maiming
« Reply #7 on: January 19, 2017, 08:18:45 pm »
So I see you guys dropped your registration. That's a drag, I was looking forward to seeing you and watching your bot maim some others (but not mine, of course)

Hope it was just a scheduling conflict and you can make it to Franklin

-Zac

samhanson

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Re: Team Balhogs: A Maiming
« Reply #8 on: February 05, 2017, 01:47:13 pm »
We'll still be there.

Things are going smoothly in spite of our lack of updates. Drove the bot yesterday. Test saw fits and is looking like it will be under weight.

Ravi_B

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Re: Team Balhogs: A Maiming
« Reply #9 on: February 06, 2017, 11:25:28 am »
Cool bot guys, glad to see you're still around!

Cya at moto, drinks will be had.

samhanson

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Re: Team Balhogs: A Maiming
« Reply #10 on: February 12, 2017, 08:47:18 pm »
Alright Sorry for a complete lack of posts,

Colin and I have been steadily working on A Maiming after work and on weekends (and in between fishing trips). The construction has gone very smoothly with everything pretty much fitting together according to the CAD. Saw bots are certainly easier than pneumatic hammer bots.



The robot drives. At 10mph it is zippy but not uncontrollable.
The saw spins. It spins up quick and consistently. The saw seems really gnarly the bot is loud and sparky and just overall seems really mean.
The armor seems sufficient with all over 3/4" birch ply, 1/2" polycarb top and .09" skin of ti in some places .
The bot is dense and it seems like it should take flips well.



We are going to take the remaining time before moto to practice driving and really dial in the bot. Oh yeah and the bot is like 26 pounds! I guess i was too conservative in the weight allotments, but this sort of thing has never happened to me before. It feels weird. We're looking forward to moto and we're excited about the two box format and seeing everyone there. I will post some videos soon but you can follow the team on instagram at @balhogs for more frequent posts and live updates from the shop.

zacodonnell

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Re: Team Balhogs: A Maiming
« Reply #11 on: February 12, 2017, 09:53:43 pm »
Being underweight is WAY easier to deal with than being overweight with 5 days to go until the show. I'm psyched that you guys are going to make it up. I definitely have very exposed wheels that don't want to fight you, but a dense robot that is 4 pounds underweight is a lot of fun for a flipper :)

Pneumatic components are way harder to fit into a robot than motors and batteries. The shapes are just so funky and so many of them are so long... Feels good to have a nice dense bot huh?

-Zac