Official OT-Creativity Thread 1

[MoD]

That's great! I have only one suggestion and question: Instead of using pulleys for the drive train, put in some gears. LEGO pulleys don't transfer force very well and from what I see in the pics they aren't needed for transmission of force over a variable distance. If there's not space on the inner part of the "legs" you could always have the gears on the outside, though that might add a need for some more red beams on the other side. The matter of transferring force might not be an issue now, but if you ever invest in a LEGO motor or two to power it they'd benefit from the change.

And the question: Why do you have the wheels all oriented exactly the same on the virtual version (I think it's different on the real one, the pics make it hard to tell)? I'd think you would have them reflected over the left-right axis, but all of the 6-circled sides are facing the viewer in both pictures. Is that a limitation of the building app?

[Indigo]

Great feedback MoD!  About the pulleys; I tried a total of 3 solutions to that problem.  I tried it with gears, chains, and the pulleys as you can see.  The chains caused too much friction and was bogging the gear rotation.  The gear solution also had friction, but not as much.  In the end I just went with what looked the best....though the chains looked pretty neat as well.  I'll play around with that a bit more.  As far as motors go, I'm buying them very soon along with a set of pneumatics that will be used on a scoop-type-device for this rover.  I plan to hook up the motors to the 2 protruding drive shafts you see there in the picture.  those drive shafts are then connected to a 'worm' gear.  That worm gear is then connected to a crown tooth gear which then spins the shaft which, in turn, spins all of the external gears you see in those pics.  I designed the rover with an opening 'hood' so you can fix the rover both in and out without disassembling anything.

here is a pic with the hood open:


You see, back when I was a wee lil lad (back in the 6th grade), I was part of a geeky team called the "Mars Rover" team.  The goal was to design a rover in which could accomplish certain tasks such as climb a certain degree incline, or pick up a number of rocks, be under a certain weight, complete an obstacle course, and others.  It was a HUGE competition held up in Idaho; tons of kids everywhere.  Very fun, yet also nerve-racking. 

My team:

I'm the scrawny kid in the middle.  Wasn't I just adorable?

Recently I've been having a bit of nostalgia.  I went on a whim to the Lego Education website and bought myself a whole slew of Mindstorm Legos in bulk (ones that matched the pieces found in the competitions sets).  The only things not included were the motors and pneumatics which I am ordering soon.   Anyway, I wanted to design a rover that'd kick that competition's butt if it were to be entered.  To my knowledge, there has been no rover entered into the competition with a working shock system, thus that obviously was my goal.

And the wheels, that was simply an oversight.  Thanks for pointing that out.

[Malor]

Caricature of my friend/priase and worship leader...first ever caricature, pretty happy with it..not to cartoonish though..but multiple proportion problems....anyways..



for a first, I am quite pleased.

[Indigo]

looks pretty good mate, but it's spelled "caricature."  Forget the 'h.'

[Evil-Ville]

Your friend is from now on called Gordon Freeman.

[Malor]

looks pretty good mate, but it's spelled "caricature."  Forget the 'h.'

yeah, noticed right after I scanned >.<

[Malor]

Your friend is from now on called Gordon Freeman.

oo a black gordon freeman..BEAST!

[Zolthorg]

Having done the robotics minicourse at queens u twice in a row, and owned my own lego mindstorms 2.0. I can tell you this Indigo.
Ditch the rubber bands, they do not work.

[MoD]

@Indigo: I've also done a competition a lot like that. It was called "First Lego League" and we used the mindstorms 1.0 and a freaked-out graphical programming language to do several tasks on a playing field with lego objects, but without any human intervention; we had to program everything procedurally with hard numbers. We didn't fare very well against the competition because of our dysfunctional team and because we didn't have any rotation sensors and nobody was inventive enough to improvise substitutes.

Your model instantly reminded me of a mars rover, probably because of the legs and flat top somewhat reminsescent of a solar panel. About the chains, pulleys, and gears, I'm still suggesting you go with gears, but that you mentioned chains made me wish I was born at a different time. By the time I got into the Technic sets they didn't use the chains much at all.

I like the idea of a openable hood for easy rebuilding, but looking in there I wonder what kind of speed you'll be getting. Instead of using a worm to 24-tooth crown I'd use a worm to a 16? tooth bevel gear or stick a different type of gear out further with some sort of brace. But I'm not familiar with the kind of mothors they had back then so they might have different speed/torque than the ones I'm used to.

[ptoing]

Looks pretty nifty, but wouldn't the gears lock up easily, or is there some logic behind it that is not instantly obvious?

La aŭto estas bizara.