Re: Exposed gears/chain
 

Thank you, this is good to know so we can have a plan in place in case we fall into the same situation.

Re: Exposed gears/chain
 

There is no requirement to comply with OSHA standards as a FRC team.

I'm all for safety but adding guards is often not actually more safe than teaching students real safety (like never working on the robot without it being disabled, or even better, off entirely).

The fact that volunteers will often invent or incorrectly interpret rules requiring changes to the robot (in this case adding guards) is a source of continual frustration. Nowhere in the manual does it say all pinch points must be protected from insertion of a finger. Obviously anything egregiously unsafe should be addressed, but that's not what is generally being discussed here.

People will reply with "But safety!!!", but there is only so much you can do to protect people from themselves and at a certain point the safety theater becomes a burden for everyone.

Re: Exposed gears/chain
 

At week 0 one of the inspectors (who is also the lead at one of the regionals) told us we will need guards for our robot to pass inspection.

We are just making a bunch of plastic disks that will slide on the axles on either side of the sprockets. They are large enough to extend past the chain and stiff even though they are fairly thin. They are held in place by the sprocket and either the frame or a collar. This way they spin loose on the axle in case you bump up against it.

Maybe I'll post pictures later.

Re: Exposed gears/chain
 

I will agree with Al on this one.

Re: Exposed gears/chain
 

Agreed. I would much rather have students protected by sound decision making skills than by chain guards you learn you have to add only once you're at the regional. Sheids etc do have their place, but chain guards are only really in a position to be helpful if you're sticking your hand inside an enabled robot. If you're doing that, you're asking to be hurt whether or not there are chain guards.

To draw a parallel to surfing: you can make everyone wear a life jacket before they can even look at water, but at the end of the day it's best to give people a healthy understanding, respect and fear of the ocean.

Re: Exposed gears/chain
 

I can't recall ever getting to work on equipment in industry before going through a certification class. If it were as easy as educating people to not do unsafe things, why are there OSHA standards? :)

I think it's safe to assume that the vast majority of people that work on or around our robots are not idiots and know that sticking their finger into a chain will have bad consequences. Accidents happen when people aren't paying attention and inadvertently put their hand where it shouldn't go.

During testing this year, I was a few inches away from getting a finger caught in a floating idler, since I forgot it had been added to the robot, and didn't check that the robot was disabled. I can assure you that I wouldn't have been close to that spot if I knew that, but miscommunication, accidents... etc.

Re: Exposed gears/chain
 

Because OSHA exists to force the employer to create a safe environment for employees when they would otherwise cut corners to save cost.

Re: Exposed gears/chain
 

I think there's an XKCD on this topic...

And this is exactly right. I also agree with Cory's "safety theater" comment: I was reprimanded earlier this year for not yelling "robot" in front of a virtually empty pit row. Is it technically safer to yell robot at all times? Probably. What are the chances that it will ever stop someone from being hurt? Near zero.

Here's a really interesting look at why school buses don't have seat-belts in them (generally): http://www.nbcnews.com/id/40820669/n.../#.VQCkwvnF_8o

This is safety design done intelligently and effectively.

Re: Exposed gears/chain
 

Robot shields can present a false sense of security. You should NOT be working on a power up and enabled robot if you are concerned about safety.

I've had to deal with OSHA regulations this year, and let me tell you, the people who write these things have never used this sort of equipment in their lives. In some cases, OSHA regulations make equipment more dangerous - such as 'safety' shields that get parts stuck against grinding wheels, saw blades...

Re: Exposed gears/chain
 

The primary "OSHA like" regulation I'd use (as someone who deals with it daily) is lock-out / tag-out, which is sufficient for purposes of working on a robot.

I'm not actually saying to apply a locking device on the computer, but in general... but either by direct control (throwing breaker) or procedure, make it well known that robots are not to be enabled when anyone is working on them.

The bigger concern I typically see is just people getting too close to robots moving (whether it be a pinch point or just something moving quickly with lots of mass). It's particularly an issue on practice fields at events, with 6 teams + drivers + pit all standing around trying to troubleshoot an issue, with moving robots less than 5 feet away from them.

Re: Exposed gears/chain
 

My personal rule of thumb is that if a system failure could cause serious injury even while the robot is properly disabled and/or unpowered (perfect example is a stored energy catapault from 2014) you should definitely implement some sort of safety device for that system.

For example, if any part of our shooter latch system would have failed last year (pneumatic system, latch control, set point check, latch pin, etc.) it would have made for a very bad day for anyone with a body part anywhere near it even with the robot properly disabled. Thus, we made sure to diligently utilize a safety strap anytime work was required around the robot when energy was stored in the catapault and the robot disabled and/or unpowered.

On the flip side, we have exposed sprockets and chains on the intake of our robot this year, but we don't utilize a specific guard or shield. The reason is because anytime the robot is properly disabled, those gears/sprockets aren't at risk of moving and causing an injury. See the difference between the two situations? If you follow general safe procedures regarding robot/person interaction and making sure the robot is always disabled and/or unpowered, you shouldn't have a safety concern regarding open sprockets and chains. Does that make sense?

Re: Exposed gears/chain
 

There's a false dichotomy being presented by many posters here. Having inaccessible pinch points and following proper safety procedures are not mutually exclusive. It's possible to both "not be an idiot" and have safety guards to mitigate the risk of accidental injury. There's enough risk of injury from accidental and unpredictable scenarios to warrant taking steps to avoid the potential for harm. I know for a fact that at least one of the teams arguing against safety shield in this thread has had a student require medical attention at an event because of an exposed hazard on an elevator of theirs in the past (albeit not a pinch point).

Re: Exposed gears/chain
 

Since you're talking about us, it's worth noting no amount of shielding would have prevented the injury.

Re: Exposed gears/chain
 

I wasn't meaning to imply that shielding would have prevented that particular injury. Simply pointing out that mistakes can and do happen, even to the teams that have established an effective safety culture.

Re: Exposed gears/chain
 

yeah this robot worries me in general... keep in mind it's a reveal video and they may have to make changes before competition
the one thing I will say about this robot is that those chains don't appear to actually move much, and there seems to be no way to cover them without damaging the functionality of the arm
(full video of them here https://www.youtube.com/watch?v=kokq6fgOOP4 if you hadn't watched it yet)