Building large wheels

[stryker001]

The attached LEGO Digital Designer CAD File may be of assistance to you with your Rover design.

ExoForceRover.zip

I really like the design you had on your blog, so I bought 4 green wheels and I'm trying to get a hold of a second turntable (there are non on BrickLink at the moment).

Ironically, this sorta defeats me learning how to make big wheels, but now I have some and I shouldn't have to worry about needing more for awhile.

I don't have LDD, but I'm gonna be getting LDraw on my new computer. Is there a LDD viewer, or do I have to get LDD as well?

[hassenplug]

I think there are a couple options for mounding those wheels.

1) Use a very sturdy attachment like sparramc posted
2) Support the outside of the axle, like JBrost did on his voyager:
http://us.mindstorms.lego.com/en-us/Com ... 291610c18b

3) Simply connect using an axle and some 1/2 wide pulley wheels.

The good side of option 3 is that it's simple. The down side is that the axles will bend, if there is too much weight on the axle. The other two options should avoid that.

Steve

[stryker001]

I think there are a couple options for mounding those wheels.

1) Use a very sturdy attachment like sparramc posted
2) Support the outside of the axle, like JBrost did on his voyager:
http://us.mindstorms.lego.com/en-us/Com ... 291610c18b

3) Simply connect using an axle and some 1/2 wide pulley wheels.

The good side of option 3 is that it's simple. The down side is that the axles will bend, if there is too much weight on the axle. The other two options should avoid that.

Steve

The master himself!

Unfortunately, this will be taking some serious weight, or else I would just use option #3. Since it's a balancing bot, the wheels are in the center of gravity, and so all the weight is put on them... If I weren't doing a balancing bot, then I could shift a lot of weight off the wheels and feel safe about using #3.

For now, though, I'll try out sparramc's design and see what I can do.

P.S. Steve, JBrost mentioned something about your "Green Monster." What's he talking about? The link doesn't work.

I was both inspired and challenged by Steve Hassenplug and his Green Monster creation (http://mindstorms.lego.com/nxtlog/Proje ... e34b98c4aa) to build a self-navigating outdoor robot of my own.

[sparramc]

I don't have LDD, but I'm gonna be getting LDraw on my new computer. Is there a LDD viewer, or do I have to get LDD as well?

You will need to download LEGO Digital Designer (LDD ) as LDraw won't import it.

LDD does have a LDraw export facility, but a lot of the Technic parts are missed completely or badly miss-orientated. As an example, the Technic Type 2 Turntable can be anywhere in your model. The Import facility is pretty good in comparison.

ExoForceRover.lxf

LEGO Digital Designer CAD File: ExoForceRover.lxf

(108.68 KiB) Downloaded 378 times

ExoForceRover.ldr

LDraw CAD File: ExoForceRover.ldr

(133.44 KiB) Downloaded 389 times

I find LDD easier to use than the LDraw Interfaces, but the Export issues are a real inconvenience though!

[stryker001]

I don't have LDD, but I'm gonna be getting LDraw on my new computer. Is there a LDD viewer, or do I have to get LDD as well?

You will need to download LEGO Digital Designer (LDD ) as LDraw won't import it.

LDD does have a LDraw export facility, but a lot of the Technic parts are missed completely or badly miss-orientated. As an example, the Technic Type 2 Turntable can be anywhere in your model. The Import facility is pretty good in comparison.

ExoForceRover.lxf

ExoForceRover.ldr

I find LDD easier to use than the LDraw Interfaces, but the Export issues are a real inconvenience though!

I'll try out LDD then. I have no idea how to use it

[hassenplug]

Here's my Green Monster:http://www.teamhassenplug.org/robots/GreenMonster/

It shows other examples of the wheels. I would most likely do what John did, and put supports on both sides of the wheels.

Steve

[stryker001]

Here's my Green Monster:http://www.teamhassenplug.org/robots/GreenMonster/
It shows other examples of the wheels. . . .
Steve

Those are amazing. Simply amazing.

And, my Gyro just came in the mail like 5 minutes ago. <3 So happy.

[mattallen37]

...And, my Gyro just came in the mail like 5 minutes ago. <3 So happy.

Would it by any chance be the dIMU?

[stryker001]

Would it by any chance be the dIMU?

If I were a rich man, Ya ha deedle deedle, bubba bubba deedle deedle dum.
All day long I'd buy fancy IMUs, If I were a wealthy man. . . .

I so wish it was. It's just the cheap gyro from HT.

[nxtreme]

Hey, I'm working on a new LEGO project and am in need of some nice big wheels (at least the size of CDs, if not a few inches larger.

Well, I have just the thing for you! I put these together almost a year ago but haven't done much with them since. I'm sure you have plenty of scratched or useless software CDs lying around, that's what I used. I botched up the notches on the inside edge of the CDs, but they still fit pretty well. I put some hot-glue on the edge of the discs for a bit of extra grip. Keep in mind, these aren't the best wheels, just the cheapest.