Re: Minibot switches and soft landings
 

At least in our setup, when the minibot can touch the deployment, the minibot is not above the deployment line.

Re: Minibot switches and soft landings
 

That should be legal.

Re: Minibot switches and soft landings
 

@Brando

Hm, I guess I was misreading rule G22 as not being able to contact the hostbot after any part crosses the deployment line, and not as long as any part is over the deployment line. In that case, I don't know what our partner's red card was given for during that match, we just assumed it was a G22 violation.

Re: Minibot switches and soft landings
 

If a deployer swings the minibot down, like a drawbridge, and as it comes down if any portion of the minibot is above the deployment line and simultaneously within the vertical cylinder of the tower and in contact with the deployer- independent of whether it is in contact with the pole, I think the referees will rule it in violation.

Here's a whole thread on it...

http://www.chiefdelphi.com/forums/sh...ent+cylind er

Re: Minibot switches and soft landings
 

Here is a little tip. McMaster Carr sells "Manual Reset limit switch" Part # 7336K51. Works like a charm. This will also allow you to create this circuit with EASE.

This is exactly how our minibot is wired....

Re: Minibot switches and soft landings
 

Is that considered a legal switch according to the rules and all the Q&A?

Re: Minibot switches and soft landings
 

Yep, it is marketed as a "limit switch" so it is allowed.

Re: Minibot switches and soft landings
 

Yes it is. The McMaster catalog lists it as a "limit switch" and it is the application for which it is most used.

Re: Minibot switches and soft landings
 

We did something a little different.

I took the Tetrix switch that is legal, took out the dremel, put on a cutting wheel and removed the on half of the toggle so that it is flush when the switch is in the off position. Now it only toggles to the off side, but can be reset to the on position.

We mounted the switch at the top of the mini-bot and when it hits the trigger it toggles and turns off the mini-bot. It can be mounted by cutting out a rectangle that is 1 inch by 1/2 inch and pressing the switch in. We designed the mini-bot a little more on the rugged side, so when gravity pulls it back down the pole it can withstand the impact.

The added bonus is that it mounts easily, is sturdy, looks nice, and the red on the switch lets you know the mini-bot is armed.

This just seemed like the simplest solution for our design and application.

Re: Minibot switches and soft landings
 

wouldn't the highlighted area on this pic cause the fuse to blow?

Re: Minibot switches and soft landings
 

What we did is find a 4 way light switch (i believe). Basically, it was a switch that flipped polarities. Then there was another switch that triggered when the robot hit the pole.

Our minibot went up, flipped the polarity switching switch, powered down, hit the bottom, and then, due to the mechanical way the wheels were rotating, fell off, and thus broke the switch that kept it powered, and turned off.

Re: Minibot switches and soft landings
 

This was the circuit diagram for our minibot.

Attachment 10548

When we short the motors, the current generated when backdriving will go through the circuit again the opposite direction. The result is a fairly slow terminal velocity when it falls.

Hope that helped.

Re: Minibot switches and soft landings
 

I did the same thing with a simple momentary switch when designing the minibot my team used. The latch worked perfectly, but we had to be careful in ensuring that the switch consistently contacted the top plate - it didn't during one practice run, which ended with a burnt out motor.
Our minibot usually stayed at the top after it had finished its run because it did not weigh enough to backdrive the motors, which ended up being okay. Unfortunately, the minibot's momentum occasionally caused it to fall off the pole once it hit the top plate, and twice it hit the ground hard at the end of a match. We needed to repair it both times. As long as your minibot has a reliable method of attaching to the pole and it does not "free fall" after it hits the top, it should survive a trip back down. You should certainly test it to make sure, though.