Saturday, September 5, 2015

The 3d printer arrives. Geeetech Prusa i3x

Well, it's about that time.  What time you might ask?  Time to build a 3d printer.

Oh look, A present from DHL.  That should give you a clue as where this came from...  

What we have here is a Geeetech Prusa i3x.  Well, at least the manual and packing list.

Lets keep digging.  Under the cardboard is the laser cut z axis frame.  You can see the cutout at the top for the LCD display.  Let lift away that layer...  

And then we get into the meat of things.  The stuff on the left are the rest of the laser cut acrylic bits to make the frame.  On the right is a PSU, and some control electronics.  What at first I thought was some wire to do the point to point wiring, is actually a few grams of plastic to test the thing out.  Good on you Geeetech!  I was worried the printer wouldn't come with any plastic, so I bought a kilogram of ABS.  The stuff from Geeetech is blue...  I should have bought blue...

Next layer!  Here we have all the rods that the axises ride on.  The four stepper motors, a small tool kit, the print head, and the rest of the control electronics.  

The tool kit really impressed me.  

Fans, limit switches, braid to keep the cabling looking nice... really it's a complete kit.

wow, I wish I did a better job with this photo.  But this is the print head.  

I should have it assembled in the next few weeks.  I'm excited!  

Thursday, July 30, 2015

Building a Better FPV Video Rig

A while back, I glued a small FPV camera to a Boscam 10mw transmitter.  It worked.  It worked great!  On a single lipo.  This.. becomes an important note.  

If you want to take a look at my previous micro FPV rig, click here:

Fathers day rolls around, and I bring my FPV gear to Michigan, to show it off to my Dad.  I plug that pretty looking JST plug, into my balance plug to JST adapter, and a whiff of white smoke comes out of the camera.  I had forgotten that my 10mw transmitter was 3.3v only.  I, in my infinite wisdom, had just fed the poor little thing 12.6v from a fully charged 3s 2200.  Whoops.

I'm a bit of a parts hoarder, so I did some digging through drawers, and came up with this little pile of parts.

Here we have the camera, a JST plug, a dip switch pack, some pin headers, some veroboard, the new 50mw transmitter, the burnt out old 10mw transmitter, and most importantly a 7805 5volt voltage regulator.

Why 5v, instead of 3.3v?  Well the 50mw transmitter uses 5v instead of 3.3.

First, I need something to work on, so I cut off a bit of veroboard.

And I started the test fitting process.  If you have the stuff on hand, always do test fits.  And do them often!

If you put a circuit board on the handle of pliars, it gets the pins out of the way, so componets will sit flat.  Here I am working out the distance between the pin headers, to see if I can mount the 7805 under the video transmitter.

Something my last camera didn't have, was a way to change channels.  This one, does!  Sadly, the cost is about 9 grams.  The whole previous rig was 9 grams, in the end, this one ends up being 17.4g.

Here's the 7805 under the VTX module.  It's a tight fit, but seems just fine in there.

And then I started soldering.  

Did anyone ever tell you how hard it is to stop, and take pictures between steps of a tutorial?  It's really very hard to remember.  Because my next shot was this:

That's the completed transmitter and camera module, with all of the protective hot snot in place.

At least it works, right?

 The antenna is just a bit of un-shielded wire.  It's cut exactly the right length for 5.8gHz.  I have some RPSMA jacks coming from surveilzone that should show up in a week or two.  Once those come in, I"ll swap this over to circular polarization.

That said, the rig works, and has decent range.  I'll try to get some real numbers on range later.

Thanks!  If there's enough demand.. I could probably clean the design up, and maybe do something silly like get a board done by oshpark or something.

Monday, July 27, 2015

The first Davis DA-2.

That, is a Davis DA-2.  Well... importantly it's the first Davis DA-2.  Some nice people flew it to oshkosh this year.  Sadly I didn't get in touch with them soon enough, so I didn't get a personal tour of it.  It was nice to get to see the original, and see how Leeon did it the first time around.  

My interest in the DA-2 is somewhat more than in passing, so I took a lot of pictures.  And with permission, from Giff, who's half owner, here's what I took.  He does call her Ugly Betty, so any of the rough edges.. well I assume he's aware of.  

Wednesday, July 22, 2015

Playing with my [gim]balls.

One of my goals is to have a "small" camera platform.  Part of getting there, is to have a gimbal to keep the camera steady, and aimed.  That means gimbals. 

In my latest order, I grabbed two cheap gimbals. 

This one is one desgined for the mobius.  It uses two 9 gram servos, and is really quite confidence inspring. 

I expect it'll do everything one can expect of a 2 axis gimbal.  I assembled it using some thing CA.  It went together fairly easily.  The only trouble spot was the servo arm on the bottom of the gimbal.  That is now just glued in place, no screws.   For about $10, it's a heck of a deal.

I also picked up a GoPro sized gimbal.  (in spite of owning zero gopros..)  It too is a two axis rig.  It uses a 9 gram servo to do the pitch, and a full size servo to handle roll.  
 It looks pretty good.  However I think the servo I had for the roll is just crap.  It had a lot of slop in it, so the whole gimbal has a bunch of slack and wiggle in it. 
Further reviews will come later, as I fly them.