Re: pic: Magnetic Grappling Hook
 

Then I guess my only real concern is if it accidentally went off and it happened to land in another robot.

Re: pic: Magnetic Grappling Hook
 

Shattering the magnets was definitely a concern. The purple side guards shown in the picture (actually made out of polycarb) extend 1/16" above the faces of the magnets, so the magnets themselves will never actually contact the bar.

Re: pic: Magnetic Grappling Hook
 

If you decide you don't like the magnets, you could always try (using the same launch mechanism) to use a purely mechanical system that latches itself upon contact, and could be made a bit more forgiving with regard to aim, like this design from this thread.

EDIT: The linked robot is from 2013, but the hook concept is the same.

Re: pic: Magnetic Grappling Hook
 

I like it, I like it

Re: pic: Magnetic Grappling Hook
 

So do I. I should correct myself though. In my earlier post, used the phrase "purely mechanical system," though the system you've designed already satisfies that criteria. I should have said a system where the grappling and latching are all accomplished in one passive (no actuator needed) motion. In any case, the system you designed is pretty sweet, I hope y'all have success with whatever you decide to use.

Re: pic: Magnetic Grappling Hook
 

I have one thing to note about using magnets, and it has to do with paying attention in the pits.

Team 1619 last year used strong magnets (I believe that we used two 75 pound magnets) to hold our canburglar in place for the rest of the match after their initial use. As one of the people who was always in the pit moving around the robot, I lost count of the number of times my driver button or a small team pin attached to my shirt became affixed to the magnet and either tore my shirt or forced me to manually detach the button/pin to prevent my shirt from tearing. We also had to be careful with electronic devices. If we used a phone for a flashlight you had to be careful not to set it near those corners of the robot (the magnets were positioned on the top of our robot's "roll cage", a generally ideal location for an overhead light to be placed). Tools and nuts/bolts also became attached to the magnets when they were passed over or near the magnets.

If you decide to continue to use the magnets, I would recommend you have the claw stored someplace in the robot that is somewhat out of the way of other items in order to minimize these inconveniences. Our magnets were positioned at perfect pin/button height (right above your belly button) on an outside corner of our robot, which made for a hassle at times in the pits.

Not a huge thing, but something to consider when using strong magnets on your robot. Make sure everyone who works on the robot understands that they are there and how large their area of influence is so that they can prevent accidents and inconveniences.

Re: pic: Magnetic Grappling Hook
 

With all of these flashy quick-release and speedy grappling hooks that are iterated on throughout the season, is anyone else having flashbacks to the minibot races of 2011?

Re: pic: Magnetic Grappling Hook
 

I am noticing a lot of people concerned about being able to quickly align the hook, but could you not put the hook and launcher in such a position on the robot that it would be properly aligned when the bumpers were pressed against the castle wall? This is what 118 did and once they had it working they hit the bar every time. I heard they missed some on practice day at Huntsville, but once matches started they were climbing very frequently.

Re: pic: Magnetic Grappling Hook
 

Watch team 2341, The Sprockets, at the world championship. We have perfected a magnetic grapple that works every time. Very similar to the one you have posted. Ours is delivered by a spring loaded arm.

Good luck all!!

Roger. Mentor