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tjspartans
18-01-2014, 14:00
Hello, I am part of Robotics class at my school that has two teams going to the FRC competition. One of the teams was wondering if they could use a 10 lb. manufactured sledge hammer to shoot the ball into the goals.
Any information that anyone could provide would be greatly appreciated. Thank you.

Mike Schreiber
18-01-2014, 14:09
There are no rules that prohibit this.

http://www.chiefdelphi.com/forums/showthread.php?t=64916

thursam
18-01-2014, 14:19
I don't see a rule prohibiting it, but there are some you have to keep in mind...

•R13
ROBOT elements created before Kickoff are not permitted. ROBOT elements, including software, that are designed before Kickoff are not permitted.

Exceptions include the following:
A. BUMPERS,
B. OPERATOR CONSOLE,
C. battery assemblies per R5-A, and
D. software and designs with source files publicly available prior to Kickoff.

•R3
The ROBOT must satisfy the following size constraints:
A. the total length of the FRAME PERIMETER sides may not exceed 112 in. (see Figure 4-1 for examples),
B. a ROBOT may not extend more than 20 in. beyond the FRAME PERIMETER (see Figure 4-2 for examples) (see G24), and
C. the ROBOT height may not exceed 60 in., except as allowed by G23.
D. Any extension above 60 in. may not exceed a 6 in. diameter vertical cylinder (see Figure 4-3 and Figure 4-4 for examples), per G23.

Those are the only rules that I can find that would limit anything on your robot.

Bob Steele
18-01-2014, 16:23
KE = 1/2 m (v)squared
Remember that mass is not as important as speed ...

blaze8902
18-01-2014, 18:11
As Bob Steele hinted, velocity is significantly more important. If your object is moving at 10m/s at weighs 10kg, then your Energy would be (1/2)(10)(10)^2
so, 500.

Double the mass; (1/2)(20)(10)^2
1000.

Double the velocity; (1/2)(10)(20)^2
2000.

Making it twice as heavy makes it hit twice as hard. Making it twice as fast makes it hit four times as hard.

If you're considering hitting the ball with an object in order to impel it, you should focus on making your "Hitting Object" faster, not heavier.

chibi_mechanic
18-01-2014, 18:41
Though I would not recommend using a sledge hammer, I haven't seen anything in the rules that would really keep you from using it besides the fact that you have to be careful that it couldn't accidentally damage another robot. As this isn't battle-bots (sadly) I would be careful what you use. The inspectors could be really picky about that. But I wouldn't rule the option out entirely.

Matt Stemple
24-01-2014, 01:01
Opportunities for possible frame parameter violation would raise the battle bots concern. I have seen teams attach all kinds of heavy items, however generally for weight management proposes and they were static not actuated.

Madison
24-01-2014, 01:15
Opportunities for possible frame parameter violation would raise the battle bots concern. I have seen teams attach all kinds of heavy items, however generally for weight management proposes and they were static not actuated.

There is no such thing as a frame perimeter violation. If the device remains within 20" of the frame perimeter, as provided by the rules, there is no issue.

If they use it in a way that is meant to damage another robot, they'll be penalized appropriately. That is a game play issue and not an inspection issue. The "Battle Bots" concern is not a real thing.

safiq10
24-01-2014, 01:21
FIRST is about being creative I'd say go for it but go with caution. Others have stated the frame rules so go for it just be careful. Also have a backup plan just incase you can't use the sledgehammer for whatever reason. Thats just my opinion though

Koko Ed
24-01-2014, 01:22
FRC Team 578 used a sledge hammer to kick the ball over the goal in 2008. It was a it or miss proposition. Mostly the robot didn't hold the ball very well so if the bot got jostled the ball would fall off so they would have to go acquire the ball again and drive back around to shoot so it wasn't very efficient.

dtengineering
24-01-2014, 01:23
I've seen a metal working vise and a small anvil used on a robot... so why not a sledge hammer.

Just remember to play some appropriate music (http://www.youtube.com/watch?v=g93mz_eZ5N4)when the judges come by.

Jason

T^2
24-01-2014, 01:24
There is no such thing as a frame perimeter violation.

See Rule G28:

Deliberate or damaging contact with an opponent ROBOT on or inside its FRAME PERIMETER is not allowed.

Violation: TECHNICAL FOUL


High speed accidental collisions may occur during the MATCH and are expected. ROBOTS extend elements outside of the FRAME PERIMETER at their own risk; no penalties will be assigned for contact between two such extended elements.

A ROBOT with an element outside its FRAME PERIMETER may be penalized under this rule if it appears they are using that element to purposefully contact another ROBOT inside its FRAME PERIMETER. Regardless of intent, a ROBOT with an element outside its FRAME PERIMETER that causes damage to another ROBOT inside of its FRAME PERIMETER will be penalized.

Madison
24-01-2014, 01:26
See Rule G28:

Got it -- but again, this is a game play violation and there's nothing about the nature of a sledgehammer that makes it more prone to violating this rule, right?

It just struck me as odd advice given the nature of the question.

BBray_T1296
24-01-2014, 02:21
That is a game play issue and not an inspection issue. The "Battle Bots" concern is not a real thing.

I don't care if they get a red card, I don't want my robot to get hit with a 10lb sledge even by accident. It would really rustle my jimmies

That being said, assuming it is appropriately contained and not a safety hazard (imagine the head flinging off mid swing at the refs), It is not otherwise illegal

Al Skierkiewicz
24-01-2014, 08:18
The sledge will be considered as a COTS part, and it needs to be included in your BOM at retail price. It also must be firmly attached to your robot and satisfy your LRI that it won't self destruct or detach while being used. Please remember that duct tape is not a fastener especially while trying to keep a hammer in your robot.

techhelpbb
24-01-2014, 08:32
So I guess it's Hammer time (http://www.metrolyrics.com/u-cant-touch-this-lyrics-mc-hammer.html)?
I would advise when this robot 'breaks it down' that doesn't include the hammer coming loose at all.

Wzup4021
25-01-2014, 11:48
•R13
ROBOT elements created before Kickoff are not permitted. ROBOT elements, including software, that are designed before Kickoff are not permitted.
[/QUOTE]

This can't possible apply to 3rd party manufactured elements. I'm 100% positive those extra Talons you ordered were made before Jan. 4th. Those pistons? Made before Jan. 4th. Wouldn't a sledge hammer fall into the same category as stuff such as this?

Whippet
25-01-2014, 11:55
•R13
ROBOT elements created before Kickoff are not permitted. ROBOT elements, including software, that are designed before Kickoff are not permitted.


This can't possible apply to 3rd party manufactured elements. I'm 100% positive those extra Talons you ordered were made before Jan. 4th. Those pistons? Made before Jan. 4th. Wouldn't a sledge hammer fall into the same category as stuff such as this?

The blue box below this:

Please note that this means that FABRICATED ITEMS from ROBOTS entered in previous FIRST competitions may not be used on ROBOTS in the 2014 FRC. Before the formal start of the FRC Build Season, Teams are encouraged to think as much as they please about their ROBOTS. They may develop prototypes, create proof-of-concept models, and conduct design exercises. Teams may gather all the raw stock materials and COTS COMPONENTS they want.

Example 1: A Team designs and builds a two-speed shifting transmission during the fall as a training exercise. After Kickoff, they utilize all the design principles they learned in the fall to design their ROBOT. To optimize the transmission design for their ROBOT, they improve the transmission gear ratios and reduce the size, and build two new transmissions, and place them on the ROBOT. All parts of this process are permitted activities.

Example 2: The same Team realizes that the transmission designed and built in the fall perfectly fits their need for a transmission to drive the ROBOT arm. They build an exact copy of the transmission from the original design plans, and bolt it to the ROBOT. This would be prohibited, as the transmission – although made during the competition season – was built from detailed designs developed prior to Kickoff.

Example 3: A Team developed an omni-directional drive system for the 2011 competition. Over the summer of 2011 they refined and improved the control software (written in C) to add more precision and capabilities. They decided to use a similar system for the 2014 competition. They copied large sections of unmodified code over into the control software of the new ROBOT (also written in C). This would be a violation of the schedule constraint, and would not be allowed.

Example 4: The same Team decides to use LabVIEW as their software environment for 2014. Following Kickoff, they use the previously-developed C code as a reference for the algorithms and calculations required to implement their omni-directional control solution. Because they developed new LabVIEW code as they ported over their algorithms, this would be permitted.

Example 5: A different Team develops a similar solution during the fall, and plans to use the developed software on their competition ROBOT. After completing the software, they post it in a generally accessible public forum and make the code available to all Teams. Because they have made their software publicly available before Kickoff, they can use it on their ROBOT.
(Emphasis mine) We can use any COTS components or raw materials manufactured before kickoff, provided that they are not modified. If we do anything to the part before kickoff, it becomes a FABRICATED PART and can not be used.