Battlebots

A new forum for battlebots enthusiasts, competitors, and fans.
 
HomeCalendarFAQUsergroupsRegisterLog inBuilders DB

Share | 
 

 Robot But I'm Not a Robot

View previous topic View next topic Go down 
AuthorMessage
jtm94
great contributor
great contributor
avatar

People Skills : 3078
Registration date : 2010-04-23
Age : 23
Location : Clairton, PA

PostSubject: Robot But I'm Not a Robot   Sun Apr 15, 2012 2:56 pm

Back to top Go down
Cody
2000+ club
2000+ club
avatar

People Skills : 5818
Registration date : 2009-03-16

PostSubject: Re: Robot But I'm Not a Robot   Sun Apr 15, 2012 3:07 pm

I didn't realize you were using Philips flat heads in your drum, probably a big reason why you sheared all the heads off
Back to top Go down
jtm94
great contributor
great contributor
avatar

People Skills : 3078
Registration date : 2010-04-23
Age : 23
Location : Clairton, PA

PostSubject: Re: Robot But I'm Not a Robot   Sun Apr 15, 2012 3:26 pm

We changed those.
That was a mistake by Mr Beard.
I urged him to get good bolts and nuts and he didn't order them until a week before finals and we never got any.

Don gave us good bolts at the competition after we lost a tooth.
At finals we had black oxide bolts, but they were just barely long enough to pass through the locknuts.

Note: This picture was taken before prelims.
Back to top Go down
Mr. P

avatar

People Skills : 2620
Registration date : 2010-12-18
Age : 34
Location : Pittsburgh

PostSubject: Re: Robot But I'm Not a Robot   Sun Apr 15, 2012 4:17 pm

everything for this robot was done in house except the teeth. they were not built to specs and with the weak bolts added to the missing teeth.

_________________
If you are not breaking stuff then you are not learning......
Back to top Go down
jtm94
great contributor
great contributor
avatar

People Skills : 3078
Registration date : 2010-04-23
Age : 23
Location : Clairton, PA

PostSubject: Re: Robot But I'm Not a Robot   Sun Apr 15, 2012 4:30 pm

Mr P for next year do we step up to good aluminum if we can get it?
The 2000 and 7000 series are too good. I do think we should use 2000 series if any because as you said the 7000 series can be harder to machine and I think it would be too much hassle.

MY THOUGHTS ON UHMW:
Use it!!!!!! It is so much cheaper than titanium and if you're in a pinch for weight you can slap it on there. I will say that was not really the case for us, because half inch uhmw is heavier than .07 inch titanium. We used it because last year we spent a large portion of the year cutting freaking titanium. Brandon would skip an entire 6 hour day of school to cut a 13 inch long piece out.
uhmw is so easy to machine, or drill, or mill, and though we didn't go up against any crazy robots, it held up. And to be honest I think that in itself supports it. With Kiski doing well I foresee a rise in wedges meaning less of a need for strong as hell armor. Note that we did use titanium for the front slopes on both robots, I would not recommend uhmw front slopes.
Back to top Go down
jtm94
great contributor
great contributor
avatar

People Skills : 3078
Registration date : 2010-04-23
Age : 23
Location : Clairton, PA

PostSubject: Re: Robot But I'm Not a Robot   Wed Apr 18, 2012 7:24 am

I really hate that we couldn't manage to get either the stagger tooth or one-tooth design to pan out this year.

Even if we had perfect teeth, I think the stagger tooth would almost always put too much stress on the drum. I think going with two teeth was rather necessary unless we re-make a smaller diameter drum that can utilize a bit thicker pipe to give me more confidence in it's strength.
Back to top Go down
Alex P. HASD Bots
great contributor
great contributor
avatar

People Skills : 2693
Registration date : 2011-03-30
Location : south west pa

PostSubject: Re: Robot But I'm Not a Robot   Fri Apr 20, 2012 6:21 pm

i would say the 7000 series aluminum would not be bad to machine at all, all you gotta do is get a good carbide endmill or insert (dependent upon lathe or mill) and figure out a good cutting speed- ((surface feet per minute) x 3.82))/ cutting diameter of endmill . aluminum overall is usually not that bad to machine just make sure you have a good sharp tool and all should go well if you have any trouble let me know, and ill do my best to help


p.s the surface feet per minute for aluminum is between
250–350
Back to top Go down
Alex P. HASD Bots
great contributor
great contributor
avatar

People Skills : 2693
Registration date : 2011-03-30
Location : south west pa

PostSubject: Re: Robot But I'm Not a Robot   Fri Apr 20, 2012 6:25 pm

correction the number for surface feet per minute i gave you is for high speed steel sorry
not sure what it is for carbide, all i know is carbide cuts much better when it is hot, which usually means higher speeds (sorry i do not have the number for carbide
Back to top Go down
jtm94
great contributor
great contributor
avatar

People Skills : 3078
Registration date : 2010-04-23
Age : 23
Location : Clairton, PA

PostSubject: Re: Robot But I'm Not a Robot   Fri Apr 20, 2012 6:58 pm

Hmm.
I will try to make use of that information.
We just use a manual lathe and stuff works out.
Back to top Go down
Alex P. HASD Bots
great contributor
great contributor
avatar

People Skills : 2693
Registration date : 2011-03-30
Location : south west pa

PostSubject: Re: Robot But I'm Not a Robot   Fri Apr 20, 2012 7:07 pm

ya thats what i got in my basement, and usually rule of thumb, for a tougher material such as titanium or hy-80 steel, for easier machinin materials usually you can get away with faster speed
Back to top Go down
jtm94
great contributor
great contributor
avatar

People Skills : 3078
Registration date : 2010-04-23
Age : 23
Location : Clairton, PA

PostSubject: Re: Robot But I'm Not a Robot   Fri Apr 20, 2012 10:46 pm

We've never really broken bits.
The only time was trying to balance Omnom's weapon by taking a bit off and it was case hardened and our teacher rushed it and snapped like 2.
Back to top Go down
Alex P. HASD Bots
great contributor
great contributor
avatar

People Skills : 2693
Registration date : 2011-03-30
Location : south west pa

PostSubject: Re: Robot But I'm Not a Robot   Fri Apr 20, 2012 10:56 pm

ya case hardening will sometimes do that to ya Sad
Back to top Go down
rdubard
mega contributor
mega contributor


People Skills : 3636
Registration date : 2009-06-10
Age : 52
Location : Ransom Everglades, Miami, FL

PostSubject: Re: Robot But I'm Not a Robot   Sat Apr 21, 2012 12:09 am

Lookin' at the pic that started the thread, I noticed you are running 2 wheels, with the front just skidding around--how does that work out? It seems to me it wouldn't push or accelerate well. For years we ran our bots like that, and when we switched to 4 wheel drive the improvement was dramatic.

But even with 2 wheel drive you could greatly improve your traction by making the wheels be closer to the front of the bot, if you got the space on each side for 2 pulleys and a belt. Lately we have been playing around with going back to 2 wheels, but putting them just under the center of gravity. If I know my physics right, this should actually give better traction than 4 wheel drive.

Just a thought--the bot looks pretty good to me 'as is.'
Back to top Go down
jtm94
great contributor
great contributor
avatar

People Skills : 3078
Registration date : 2010-04-23
Age : 23
Location : Clairton, PA

PostSubject: Re: Robot But I'm Not a Robot   Sat Apr 21, 2012 1:52 pm

I know, I know... I said things like this the whole year. I know how the wheels should be near the center so when it drives forward the front will lift and allow it to drive great.

We compensated for it by placing a 45lb magnet behind the wheels dead center in the back which took weight off of the front and added traction.

On our school floors and hallways it really didn't drive bad, in an arena with a metal floor... It drove fantastic.
Back to top Go down
rdubard
mega contributor
mega contributor


People Skills : 3636
Registration date : 2009-06-10
Age : 52
Location : Ransom Everglades, Miami, FL

PostSubject: Re: Robot But I'm Not a Robot   Sun Apr 22, 2012 3:42 pm

I like it. Floors that the magnets can pull are not a 'given,' but when that's an option, this is a great idea! Which do you think would weigh more, the magnets or the belt system to get the wheels at center of gravity? I am certain that the magnets will give you better traction, tho.
Back to top Go down
Mr. P

avatar

People Skills : 2620
Registration date : 2010-12-18
Age : 34
Location : Pittsburgh

PostSubject: Re: Robot But I'm Not a Robot   Sun Apr 22, 2012 3:51 pm

If being flipped upside down would never happen we could move all the whels forward to the weapon. All the weight would be over the wheels. But once flipped over you are done. I believe it was west mifflin that tried this concept. I love different and this was different. Once flipped it was over for the match. The wheels to the back help drive flipped. Also the long run helps keep the weight forward and the plates to the ground. It made if very hard to get under the front of the robot. The magnet weighed less than the 4 pulleys, two wheel shafts and the belts weighed to move the wheels forward. Plus I always like to follow the K.I.S.S. Method.

_________________
If you are not breaking stuff then you are not learning......
Back to top Go down
rdubard
mega contributor
mega contributor


People Skills : 3636
Registration date : 2009-06-10
Age : 52
Location : Ransom Everglades, Miami, FL

PostSubject: Re: Robot But I'm Not a Robot   Sun Apr 22, 2012 3:59 pm

Yeah, I figured the magnets would be lighter. I have been advocating for vacuum downforce for years now, and some members of the team are interested, but it consistently becomes a space/weight/difficulty-of-implementation issue. If you have magnetic floors, there really is no better option than magnets.

Have any of your magnet downforce bots ever lost because screws/debris stuck to the bottom and made the wheels no longer touch?
Back to top Go down
jtm94
great contributor
great contributor
avatar

People Skills : 3078
Registration date : 2010-04-23
Age : 23
Location : Clairton, PA

PostSubject: Re: Robot But I'm Not a Robot   Sun Apr 22, 2012 5:31 pm

Quote :
Have any of your magnet downforce bots ever lost because screws/debris stuck to the bottom and made the wheels no longer touch?
We lost with Game Over due to there not being enough ground clearance on the bottom and with the unevenness of last year's BotsIQ floor the magnet would actually end up touching the floor, and believe me, when that magnet touches solid metal.. you're done.
We also had the magnet fall through the bottom one match and it made the robot part of the floor.
After fixing that though we were fine.

I believe Steel Center had a magnet issue this year??

This year we had the magnet a little bit further up and over top of the lexan and it never caused us to get stuck.

I'm a fan of magnets. I believe that if the Honey Badger(Black Mamba) could have drove well instead of being a sitting duck this whole year it could have went significantly farther in the competition, but that robot was a prime example of placing the wheels far back with 90% of the weight on the front and not being able to push it.
Back to top Go down
Sponsored content




PostSubject: Re: Robot But I'm Not a Robot   

Back to top Go down
 
Robot But I'm Not a Robot
View previous topic View next topic Back to top 
Page 1 of 1

Permissions in this forum:You cannot reply to topics in this forum
Battlebots :: Team Update Pages :: Clairton High School-
Jump to: