pic: 3729's minibot

[NOV8R]

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[PingPongPerson]

Looks great! How fast does it go?

[Brandon Holley]

Did you have any issues with the cantilevered shafts hanging off each motor? What kind of times are you running?

Looks good!

-Brando

[bearbot]

is this the only view we can see wats the back look like

[NOV8R]

No issues with the cantilevered shafts. The motors are mounted on 1/16 inch Lexan which allows them to flex a little. This afternoon the minibot was climbing in 1.8 secs.

[rcmolloy]

How much does it weigh?

[NOV8R]

2,4 lbs

[bearbot]

just wondering is the mount between the motors support the battery

[Chris is me]

Originally Posted by Brandon Holley

Did you have any issues with the cantilevered shafts hanging off each motor? What kind of times are you running?

You can get through approximately a regional on cantilevered shafts.

I would recommend supporting them fully but this will win you matches as is.

[trilogy2826]

2826 uses cantilevered shafts similar to this made from 1/4-20 grade 2 bolts arbor pressed onto the motor shaft. We were really worried about this being an issue at fist, so we built 3 bots. Since, we have had at least 75 successful deploys with this design in practice and we just won the Wisconsin regional (thanks 111 and 2702) where we deployed successfully 12 of 16 matches and probably could go at least through St Louis with the same minibot.

[WarehouseCrew]

What type of material is used for traction on the shafts? I've heard that the surgical tubing won't work, so curious what material (and where to get it) was used. This is a great design.

[Chris is me]

Originally Posted by WarehouseCrew

I've heard that the surgical tubing won't work,

Try it.

[PingPongPerson]

What are you using for switches?

[Ankit S.]

That looks a lot like our minibot

[NOV8R]

A few answers: The shafts are 2 inch long by 3/8 inch aluminum rod drilled with a 3/32 drill. They are then pressed on with an arbor press. The friction material is 3/8 inch OD Latex stretched on after running hot water over it for a few seconds. The white object just below the motors is a pole guide made from a 1 1/2 pvc pipe fitting. In addittion two magnets help hold the minibot to the pole. The battery is held in position between two pieces of 1/2 aluminum tubing. Inside this tubing are guide pins attached to the deployment tray. There are two on/off lamp switches and one limit switch that control the motors. The first switch turns on the motors when the bot contacts the pole. When the second switch contacts the top of the tower it shifts the motor to half power so the bot will slowly decend the pole. A limit switch on the bot's base then turns off power when it comes down the pole and makes contact with the base. Weight management of the minibot is essential. Let the bot get to heavy and you'll smoke the motors.