Compact endgame string shooter idea

I built a concept string shooter design that fires two projectiles for each mechanism. It was meant to be as a compact as possible to allow more space for the robot, and the possibility of adding more of these types of mechanisms. Currently, the design is a c channel about 6” long



Current problem with the design is that the standoffs bend like crazy.

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What’s the plastic bit on the catapult’s arm that connects it to the rubber bands?

If i had to guess its a modified bearing

This is also a problem we faced. It could be a combination of the hard stop and the rubber band pressure. I would try to make the standoff on the catapult run into something softer or more absorbant then another standoff

its a type of bearing that can be bought in the vex store, i think its to keep nuts in place

correction: standoff retainer

It looks like the new standoff retainer: Standoff Retainers - VEX Robotics

A clever idea for making linear sliders!

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which standoff is bending

4D11CCC0-7B52-4826-9475-28759D54F196

I think this one

How far does it launch? Those rubber bands make it look like it would launch across the field in the air so a less powerful version would be just as effective but not as prone to bending its pieces.

oh dang, could you use a hs axle and drill into it?

I made a second arm design that doesnt bend (or as much)

This looks really cool! What is your method of deploying it?

Our area banned metal projectiles of any sort, so I had to use plastic, so it only travels like less that half the field length

I tested a metal nut and it worked good, but had to modify the double prong

What area is this? It should not be possible for a region to change the rules.

R4 gives the head referees quite a bit of leeway to interpret what might be considered dangerous. While not necessarily “changing the rules”, a group of head refs in a particular region (head ref’s tend to talk to each other…they don’t work in a vacuum), might all decide that shooting big metal nuts across the field might be a potential safety hazard, especially if a robot might accidently discharge a metal projectile by accident into someone’s face.

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What is the standoff connected to so it doesn’t fly off?

Welcome to the forums!

What I did when I made it is I put a double ended screw (standoff connector) in the screw hole of a shaft collar (take out the baby screw) and then put the shaft collar on a screw joint. Hope this helps!