Check out (and critique) my robot design (Aluminum Body, Palm Powered, Motors)

[corrado33]

Hey guys, so I've finished my cad sketch of my bot, check it out.  I made it with sketchup, and I've colored it by parts I have to make, parts I have to buy, and parts I have.  I've put the part model numbers in the description if you click on the part.  Some of the parts are in groups so if you're familiar with sketchup you'll have to go into a component to actually see the part.  Here's the link for the sketchup file (SOR won't accept sketchup files for upload). http://www.box.net/shared/zz4zim6lkg   Make sure you turn on X-Ray view and "color by component" for best viewing.  

So as for the information about this model.  You probably haven't guessed, but this robot is basically part of a larger modular robot.  This is (obviously) the locomotion section.  I am going to build extensions that fit over this robot.  The four linear actuators (with metal parts on top) are used to clamp down the extensions by first extending into the extension, then something is put under the metal part, then the metal part is retracted until it is tight.  (I'll be making an animation shortly.)  I might also plan on using these "clamps" as communication "wires" between the locomotion bot and extensions, but that's just an idea. (I mean aluminum and steel are both conductive so...)

Oh yeah, I almost forgot, this is a Palm Powered Robot as it'll be powered by my Palm Tungsten T2.  That's what the big green cube is if you're looking at the sketchup file.  

As for the extensions I want to build...
Vacuum robot (like roomba) -- I know this'll be hard, but I want to do it.  
Mopper robot
Garage helper. (Holds tools, gives you ones you ask for, aka "3/4 inch wrench" and it'll give me a 3/4 in. wrench.)
Haven't thought of anything else yet...  

Anyway, here's the list of parts used.

Motors: BH31 Geared Motor 31:1 (Robot MarketPlace) http://www.robotmarketplace.com/products/0-BHG31.html
Wheels: Kornylak Corp. "Transwheel" model number: 2052-3/8X http://www.omniwheel.com/transwheel/transwheel-2000.htm  (search for 2052-3/8X)
Hubs: Mini Aluminum Hub set of two - 6mm bore (Robot MarketPlace) http://www.robotmarketplace.com/products/0-MHUB04.html
Linear Actuators: From McMaster Carr Model Number 70155K1 or 70155K2 http://www.mcmaster.com/#linear-actuators/=44b7hw
Body: Made out of two different thicknesses of Aluminum (3/32 in. for bottom, 5/64 for the rest)) http://www.metalsdepot.com
Batteries: Haven't planned for them yet.  They'll fit somewhere, most likely on the bottom level.  If I don't have enough room for one battery pack, I'll buy smaller ones and chain them together, therefore theoretically making one larger battery pack.  I mean battery packs are only individual batteries chained together anyway.

I am going to make some PCBs for my electronics (hopefully).  And yes I realize I'm going to need a bunch of motor controllers etc.  I understand the electronics, it'll just be interesting to see if I can make it work.  

Please feel free to critique my design.  I know the motors are overpowered, but I'm planning on making a good investment so I can use these parts for the future.

[madchimp]

Since you are useing omni wheels why not just use three which would cut cost.

[corrado33]

I decided to use four because of the article on omniwheels on this site...

http://www.societyofrobots.com/robot_omni_wheel.shtml#3vs4

Plus I like the symmetry of it, and honestly it's just an opinion thing.  

Also, I forgot to mention.  Everything is to scale which made it a pain to actually put into the computer.  I wanted to make sure everything actually fit correctly.  

EDIT:  I just looked at the picture, and it looks like the red "cubes" are above the green cube.  They aren't, just red I guess shines through green easily.  The green cube is on a level above anything red.

[corrado33]

Hey guys, I finally have the power to start building the body of this design.  I couldn't really use a saw in my dorm room at college!  I'll eventually post a build thread, but for now I'm just going to be cutting the metal pieces out. 

My brother has a media blaster, because I'm recycling some old metal I had used from another project, so everything will turn out nice and pretty.  Also, my uncle does powder coating, so if I build everything nice and neat, I'll have him powder coat it for me.  That'd look cool!

I'll probably have to have my brother weld the pieces together, as he hasn't taught me yet, and in his previous job he welded every day, so he'd probably do a slightly better job than I would.

I'll keep you updated!