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BrandonQ
09-02-2011, 15:52
A few questions about the minibot, created with mostly tetrix parts...

1. The "mini-kit" we're using at the moment doesn't have much in terms of controllability. It seems that we have two motors, one on-off switch, a battery, and nothing else. How are teams controlling these things?

2. Even though plexiglass isn't polycarbonate, it's not allowed as a substitute, I assume

3. Are springs allowed on the minibot? The rules don't say anything about them, but we -are- allowed to use rubber bands and surgical tubing.

4. Are we allowed to use any other electronic components, such as resistors and relays?

Thanks for the help
EricH
09-02-2011, 15:55
2. Even though plexiglass isn't polycarbonate, it's not allowed as a substitute, I assume

3. Are springs allowed on the minibot? The rules don't say anything about them, but we -are- allowed to use rubber bands and surgical tubing.
Correct on plexiglass (acrylic) not being allowed for polycarb.

Springs are not allowed on the Minibot, because anything not specifically permitted is prohibited (first line of <R92>).
Chris is me
09-02-2011, 16:12
1. The "mini-kit" we're using at the moment doesn't have much in terms of controllability. It seems that we have two motors, one on-off switch, a battery, and nothing else. How are teams controlling these things?

Since the robots must be completely autonomus, we are just having a switch trigger as the minibot is deployed, powering the motors.

Even though plexiglass isn't polycarbonate, it's not allowed as a substitute, I assume

Acrylic is not allowed. Also, it would quickly break anyway.

Are springs allowed on the minibot? The rules don't say anything about them, but we -are- allowed to use rubber bands and surgical tubing.

The rules prohibit anything not on the whitelist of allowed parts. You are also not allowed to use stored energy to vertically climb the pole, other than through the battery (e.g. the minibot must climb using the tetrix motors)
BrandonQ
09-02-2011, 16:45
Ah, we wanted to use the springs for a small gripper, but now I see that they're not allowed (Replace with surgical tubing, maybe)

Also, since limit switches are allowed, are there "permanent" limit switches (That remain off after they flip off, for when the robot hits the top)? As far as I know (Which isn't much), they are only temporary.
Jared Russell
09-02-2011, 16:50
You are allowed to use up to two household light switches in addition to limit switches.
BrandonQ
09-02-2011, 18:17
One more question...

For speed, what would the best gear ratio for an indirect drive?
BrandonQ
09-02-2011, 18:24
One more question...

For speed, what would the best gear ratio for an indirect drive?
PAR_WIG1350
09-02-2011, 19:30
It depends on wheel diameter and whether or not you left the gearhead on or not.
LV1601
09-02-2011, 19:50
Can we change the battery out I found a 12v 3000mah NIMH battery that is lighter weight
ratdude747
09-02-2011, 19:54
Can we change the battery out I found a 12v 3000mah NIMH battery that is lighter weight

NO!

you must use the kit battery or an identical tetrix battery. no exceptions.

::rtm:: ::rtm:: ::rtm:: ::rtm:: ::rtm::

please read the manual. it has the answer to your question directly stated.
BrandonQ
10-02-2011, 11:31
Question: does anyone know if any DPDT "household light" switches exist, and if they can be used? Or do they all have to be the "standard" SPDT? (I know that we can also just attach two SPDT's together)
Al Skierkiewicz
10-02-2011, 12:29
Brandon,
I have seen them but they are not generally on the shelf since the demand is so low.
Tristan Lall
10-02-2011, 12:43
Question: does anyone know if any DPDT "household light" switches exist, and if they can be used? Or do they all have to be the "standard" SPDT? (I know that we can also just attach two SPDT's together)You can buy them, but they're expensive. Try this (http://www.kyledesigns.com/product/5686-2W-MAINTAINED/White-Double-Pole-Double-Throw-Maintained-Contact-Rocker-Switch.html) or this (http://www.fruitridgetools.com/storefrontprofiles/DeluxeSFItemDetail.aspx?sfid=136763&i=244676560&c=7739), or search the internet for "DPDT Decora" (which is a line of wall switches made by Leviton and copied extensively).

If it's a light switch meant to be installed in a household wiring box, it's fine. (This could lead to some interesting designs using non-North-American switch types.)
SushiKitten
10-02-2011, 19:58
On the topic of house switches does anybody know if we can disassemble the switch. As far as I know that is still allowed but I just want to make sure. also if someone could tell em how to find a Q & A forum or something of the sort so I can direct my questions there next time. Thanks.:)
Mike Betts
10-02-2011, 22:02
To post an official Q&A question go here (http://forums.usfirst.org/forumdisplay.php?f=23). Look for the link "Submit your questions here! (http://forums.usfirst.org/forumdisplay.php?f=1466)". Read the GDC announcement "How to post questions (http://forums.usfirst.org/announcement.php?f=1468)".

Most importantly, search before you post (Has your question already been asked and answered?).

Be prepared to wait. My team asked a question a few days ago and we are still waiting for an answer.
Al Skierkiewicz
11-02-2011, 08:59
Sushi,
You may not disassemble the switch. You may modify (drill) the handle to attach a mechanism or modify the mounting brackets to facilitate mounting.
Mr V
11-02-2011, 12:10
Question: does anyone know if any DPDT "household light" switches exist, and if they can be used? Or do they all have to be the "standard" SPDT? (I know that we can also just attach two SPDT's together)

They should be in any decent hardware store but you'll need to look for one marked "4-way" switch. They are specifically noted in the current manual revision so yes they are legal.
SushiKitten
11-02-2011, 15:29
Thanks for the help.