pic: Simple hook delivery system

[fiona.crush1011]

If you miss, can you retract it back in to use it again?

[z_beeblebrox]

Originally Posted by fiona.crush1011

If you miss, can you retract it back in to use it again?

I don't think they can.

[s_forbes]

Originally Posted by fiona.crush1011

If you miss, can you retract it back in to use it again?

It's a one-shot deal. We have to reload the launching mechanism before each match.

[IamBuild]

I strongly think climb is within reach for just about everyone (To the point where I'm thinking about designing a "Climb in a box" cheesecake).With only 3.3 ounces I made a launch tube, hook, and rope that has a 95% success rate. It's shot with pneumatics and if you include the motor, winching system, and the solenoid, the whole system can weigh under 3 pounds. If you have any questions about this feel free to ask and I have some pictures of it here: https://docs.google.com/presentation...it?usp=sharing

[trumpthero786]

Originally Posted by IamBuild

I strongly think climb is within reach for just about everyone (To the point where I'm thinking about designing a "Climb in a box" cheesecake).With only 3.3 ounces I made a launch tube, hook, and rope that has a 95% success rate. It's shot with pneumatics and if you include the motor, winching system, and the solenoid, the whole system can weigh under 3 pounds. If you have any questions about this feel free to ask and I have some pictures of it here: https://docs.google.com/presentation...it?usp=sharing

Woah. That's awesome. It's like a piston, but the extender is the hook. I like that 95% success rate (don't know what the sample size is, though) but it seems a little surprising with that hook design. I would expect it to fall off easily. Do you have video of you testing it?

Edit: Just read the line "Hook is made to rebound off the slant behind the hook on the tower to then be pulled back and grab on." This seems more feasible for the hook design.

[IamBuild]

Originally Posted by trumpthero786

(don't know what the sample size is, though) but it seems a little surprising with that hook design. I would expect it to fall off easily. Do you have video of you testing it?

Edit: Just read the line "Hook is made to rebound off the slant behind the hook on the tower to then be pulled back and grab on." This seems more feasible for the hook design.

Sample size is out of 40. The idea behind it is the round bar near the base causes it to rotate towards the heavy side (The hook) when getting pulled over. It seems to work nearly 100% of the time if you go slowly. But even when pulled quickly it has a tenancy to bounce off of the tower and center itself onto the bar. The margin of error is pretty big especially when it is shot up close to the wall so even if it hits lower down on the tower it has enough power to ricochet off the slope and over the bar.

[Kevin_Crossland]

Originally Posted by IamBuild

I strongly think climb is within reach for just about everyone (To the point where I'm thinking about designing a "Climb in a box" cheesecake).With only 3.3 ounces I made a launch tube, hook, and rope that has a 95% success rate. It's shot with pneumatics and if you include the motor, winching system, and the solenoid, the whole system can weigh under 3 pounds. If you have any questions about this feel free to ask and I have some pictures of it here: https://docs.google.com/presentation...it?usp=sharing

Funny enough this is actually almost identical to my original idea. I'm curious, have you passed inspection with this system yet? Is this mechanism legal, it would appear to conflict with rule R76, specifically
"Do not, for example, paint, file, machine, or abrasively remove any part
of a pneumatic COMPONENT – this would cause the part to become a
prohibited item. Consider pneumatic COMPONENTS sacred."
please let me know if this would be legal, cause I'd love to use a system like this on our own robot

[JesseK]

Originally Posted by Kevin_Crossland

Funny enough this is actually almost identical to my original idea. I'm curious, have you passed inspection with this system yet? Is this mechanism legal, it would appear to conflict with rule R76, specifically
"Do not, for example, paint, file, machine, or abrasively remove any part
of a pneumatic COMPONENT – this would cause the part to become a
prohibited item. Consider pneumatic COMPONENTS sacred."
please let me know if this would be legal, cause I'd love to use a system like this on our own robot

It looks like it's a literal air cannon - there are no pneumatic cylinders involved. The fitting isn't modified, it's just attached. Inspection would be easy so long as the housing for the canon isn't PVC, PolyCarb, Fiberglass or other material that is prone to splintering during an extreme failure event.

[Kevin_Crossland]

Originally Posted by JesseK

It looks like it's a literal air cannon - there are no pneumatic cylinders involved. The fitting isn't modified, it's just attached. Inspection would be easy so long as the housing for the canon isn't PVC, PolyCarb, Fiberglass or other material that is prone to splintering during an extreme failure event.

the question I guess would be if it classifies as pneumatic component, I figure if worse comes to worse it's a pressure relief with a conveniently placed harpoon

[joeojazz]

What type of pneumatic cylinder do you use?

[s_forbes]

Ours just uses the pneumatic cylinder as the latching mechanism to release the crossbow. We just used a 1" or 2" stroke 3/4" bore cylinder. The latex tubing stores all of the energy that fires it up to the bar.

I put the parts into CAD based on memory, since the real mechanism is in the bag. Here's a better angle (click for bigger image):