OK,
It is that time of the year again. But I don’t know if it is needed. Do you want me to continue the tradition this season?
While this has already posted in other threads. Checking your robot against the inspection check list is always a good first (and and last) step.
I have always found it quite valuable and insightful, and appreciate your willingness to continue.
My question: We are planning on using a rope climbing system that consists of a rod with protruding bolts (~2" in length) that will catch and wind the loop on the end of our team rope (rotating at about 3 rev/sec). We plan to have a safety pin installed as a hardstop whenever the robot is not on the field to prevent rotation. Is this sufficient safetywise, or would there be other things that RIs would like to see?
Our robot this year will have 4 ‘harpoons’ that are propelled via surgical tubing and will fire at the start of autonomous, will a lip to retain the harpoons be sufficient for transport or should we plan on installing pins to hold them in for transport? Would there be any safety issue with transporting them fully extended other than possibly getting through doorways?
Just in case anyone thinks I’m joking with this, I’m not.
EDIT: And Al, I am genuinely being serious, we don’t have any real safety mechanism holding them back at the moment. If they hit someone it would be about the roughly equivalent of being thumped hard. Not an issue when at robot height but up higher and eye height could be a concern. Should we plan on this being pointed out as a safety concern and have a plan to resolve it?
As long as the harpoons remain within whichever volume (A or B) you choose you should be fine.
I find this hilarious. You guys finally figured out how to work this #recyclerushtb
See edited addendum above but we are definitely within volume.
If you are indeed serious then a video is in order before any serious discussion on legality and safety can be addressed.
Are y’all working on a throwback to your harpoons in 2015?
I would have to start by asking what is your definition of a “harpoon”. My definition is a projectile that travels a distance by force applied to said projectile with the intent of puncturing an object (living or not) and then preventing that ‘harpoon’ from being pulled from the target object.
I can think of nothing that would fit inside the 2017 robot rules and be effective in this year’s game.
I would continue to need to evaluate the ‘harpoons’ by actually seeing them in person and in action.
In my opinion, a hard thump would cause me great concern under R07:
R07. ROBOT parts shall not be made from hazardous materials, be unsafe, cause an unsafe condition, or interfere with the operation of other ROBOTS.
Time to change the title of this thread to “FRC 900 2017 Robot Teaser”
‘Harpoon’ is perhaps a stretch then and a bit artistic on my part. It’s definitely a contained mechanism within the volume restrictions allowed.
It definitely extends and does so quickly. Pneumatics would fall under that too then wouldn’t they? I mean, ours is far less than 60 lbs of force when extending and is doing so with some small surgical tubing. Would pneumatic extensions also be a concern?
I think the concern behind “harpoon” that separates it from pneumatic pistons is the controlled aspect of it. A piston has a very controlled motion - it travels a set distance in a straight line, no farther. A harpoon, on the other hand, implies a more uncontrolled launching of a shaft. It may be constrained distance wise with a cable, but once it’s launched it can travel anywhere based solely on the momentum within the harpoon.
So when you say harpoon, I picture the devices you built a champs for Recycle Rush. The total travel distance was constrained, but once launched the harpoons went where they wanted, bounced off things and changed direction, etc.
A video of the device in question would really help us understand what you’re trying to describe.
Sadly I don’t have a video to post at the moment. These devices are held within a slot and cannot bounce or extend beyond their intended extension distance, which is within allowed robot volume.
So it’s not so much a harpoon as a surgical tubing powered linear actuator?
If any one of us CMP LRI’s is qualified to inspect a FRC Team 900 harpoon system, it’s Chuck. :ahh:
Yeah, but that sounds so much less whimsical and interesting.
Also, to be clear, I am seeking an answer as to if we should have a system to pin them in place for transport. We don’t currently.
Oddly enough, I was actually the one to inspect them before Einstein two years ago 
Chuck didn’t want to go anywhere near it 
Without actually seeing it, I would say there should be some system to ensure it does not extend while being transported. I could easily envision a situation where something extends unexpectedly and hits someone in the stomach, chest, face or arm and causes them to drop the robot. I’m thinking back to 2014 with all the catapult robots that used surgical tubing, and the safety interlocks we wanted on them to prevent injury during transport, I can see this as being a similar situation.
But again, that’s all said without seeing it or knowing exactly how it works with respect to the rest of the robot.
Easy enough to add them I think. We’ll investigate possible solutions. Thanks for the feedback and for the inspection in 2015!
Marshal,
In all my years as an LRI (14th season now), I have been hit, scratched, thumped, have had mechanisms fall on my arms and fingers and have experienced untold hundreds of near misses. I would rather that any of those would happen to me than to a student, a volunteer or a member of the public who just happens to be in the wrong place at the wrong time. It is the job I have agreed to perform and I know the hazards. I expect all inspectors to view mechanisms with the same scrutiny and to rule fairly on the safe implementation of said items. I do not want all teams to think about what Al would say about their robot but I do want everyone to think about safety and the effect it has on others.
As a general statement, I don’t believe transporting any device in an energized state sound engineering practice, even if locking devices are in place.
As to pneumatics, yes, I believe they can also be unsafe when implemented as you describe. It really does not matter how the energy is transferred to a device if the action can result in injury. Pneumatics will/should be evaluated in the same manner as springs, surgical tubing or deformed robot structure.
This year, I anticipate a lot of inexperienced people on the field performing reset. No one knows the danger of your bot except your team and then not likely all of the team.
However, as you are likely to think while reading this post, I cannot possibly rule on a system without seeing it in person. If you asked this question of the Q&A, I am quite sure that would also be the official response as well.