Yet another MINIBOT thread....

[Bmarquez]

I ask this question just because last time i was in the class there was a mild argument about it...

Is it legal to bypass the NXT brick and wire in limit switches to complete the circuit to power the motors directly?

its a point of interest to see if i have to CAD up a aluminum sheet mounting bracket.

Thanks for any help out there!

[EricH]

Yes, it is legal. Q&A has said so. (You also have a pair of light switches, any commercially available home-improvement type.)

NXT/switch control:
http://forums.usfirst.org/showthread.php?t=16261
http://forums.usfirst.org/showthread.php?t=16144
http://forums.usfirst.org/showthread.php?t=16188

Light switch:
http://forums.usfirst.org/showthread.php?t=16189

Bypass the NXT? Who says it even needs to be on board?

[Bmarquez]

Thank you for the quick response last night! i went to sleep right after i posted xD


however with those threads seems 2 limit switches are the way to go for my team then =D

[klmx30302]

In terms of using limit switches you will need one that activates the minibot when it hits the pole and another "latching" limit switch for when it hits the top, with out the latching switch the minibot will start climbing again every time you try to get it down.

[Mark McLeod]

Just a caution...

Typical limit switches are not designed for the kind of 7amps power you'll be getting by direct connecting the battery through the limit switch to the motors. Make sure you use a heavy duty one.

That's why household light switches are permitted. They can handle the power.

[klmx30302]

Originally Posted by Mark McLeod

Just a caution...

Typical limit switches are not designed for the kind of 7amps power you'll be getting by direct connecting the battery through the limit switch to the motors. Make sure you use a heavy duty one.

That's why household light switches are permitted. They can handle the power.

One of our mentors spent several hours looking for heavy duty enough limit switches (20A) and found some.

[JB987]

Originally Posted by klmx30302

One of our mentors spent several hours looking for heavy duty enough limit switches (20A) and found some.

Any chance you could share the source of heavy duty limit switches with the rest of the FIRST community? And thanks for sharing your minibot development efforts so far!

[klmx30302]

I will when the mentor orders them and i can get the link.