Friday, March 22, 2013

Frame Finalities

Waterjet parts are in! I've already talked about the frame design, so on to the pictures:

The frame, coming together.  At this point I hadn't yet drilled holes to attach the angled braces, so they aren't pictured.

The frame, plus DAT WHEEL.  You know, for scale.
 Unfortunately, some of our waterjet parts got lost in the order to Big Blue Saw-- and these parts included the front pieces, which would have held the steering kingpins and attached the front bar to the rest of the frame :\  So it's sad that the whole thing couldn't come together today, but I temporarily used the prototyped pieces to show what the frame will look like.

It's up on the table now, so no WHEEL, but this is the final frame-- you know, with some replacements.

I've got some pictures of mechanisms that I like a lot: first, unconventional 80/20 attachments, for unconventional 80/20 angles.

For the large angled 80/20, I drilled hole at a 20 degree angle into the metal, and then milled out a larger hole for the head of the screw to go through.  The bottom of the bar is connect (as you can see in the second picture) with an 80/20 T-nut, and (as you can kind of see, in the whole frame picture), the top of the bar is connected by tapping the end of the 80/20 cross-piece bar, and screwing into that.

Second, I really like the kingpin steering mechanicism.

These milled-out aluminum blocks (right) will be the mounts for the front wheels.  They will fit between the two steering plates and the bolt (left) will allow rotation about its bearings. The steering wheel, and rider control of the steering, will link to the blocks' bottom plate.

There will be pictures when this happens, and those will be a better explanation.

Next up: attaching wheels, both front and giant back, along with steering!

Friday, March 15, 2013

Prototyping Prototypes

Oh man, putting things together!

So for the last couple weeks Helena and I've been SolidWorksing and designing things.  We've had to move the seat part of the frame apart a little (turns out: it would be hard for humans to fit in a ten inch space...) but we managed to fix it before we cut 80/20, and our frame design is pretty final:

ooh shiny CAD!

So now, before we cut / waterjet these connectors, we have to prototype them in wood (to make sure they work and hold the metal together).  pics pics pics:

wood prototypes, with tiny wooden lasercutter poops

And here are the wooden connectors with our cut 80/20.  soooo let's see if things go together!

and they did! I personally am really excited to have a physical object and not just drawings in a notebook.  Next up: more frame, connected with metal.

Monday, March 4, 2013

ObnoxiousKart: The Beginnings

This post, and probably several following it, are going to be about GOKARTS.  Specifically, one gokart, specifically obnoxiouskart (a.k.a. TriKart, FatKart, MiloKart, and others.).  ObnoxiousKart is the brain-child of myself and Helena Wang, and is an ongoing project in the class Design and Manufacturing (a.k.a. 2.00gokart).

First comes first: our designs, let me show you them.

Helena's idea sketches
My preliminary design
When we came up with the idea for a three-wheeled cart, we decided to theme it after three-wheeled motorcycles, with two wheels in the front and one in the back.  The front wheels are the turning wheels (controlled by the steering), and the back wheel will be driven.

In order to prevent the whole thing from torquing when weight is placed on it, we decided to make the frame two levels high (we're going to use a lot of 80/20 in this frame).

This drawing is a little more to scale for what the actual frame will look like: 1 block = 4 inches.

And, of course, in order to balance out the cart, the back wheel has to be huge.
dat wheel
This huge.

At this point, we've ordered some materials (see also: WHEEL), but we haven't gotten to building anything yet.  In the coming weeks: looking forward to cutting 80/20 and attaching it with our prototyped connectors. Lazzorcutting!