Author Topic: Laser cutting is awesome  (Read 5039 times)

0 Members and 1 Guest are viewing this topic.

Offline GHFTopic starter

  • Jr. Member
  • **
  • Posts: 29
  • Helpful? 0
    • GeeksHaveFeelings
Laser cutting is awesome
« on: July 16, 2008, 12:34:40 PM »
Continuing my work with the Quadricopter (quadrotor helicopter; you can find minimal information about it in the Member Tutorials), I have been looking into getting this produced on a larger scale than just for myself. Of course, it would be difficult for others to reproduce my work (the whole point of this project) if all of it has to be made by hand. So, my second (third, really, the second revision never got made though) revision of the Quadricopter hardware would be produced with laser cut plastic:

Click for larger, not transparent image

All of the mechanical hardware used in this design, including the laser cutting, materials, and brushless motors (a biggie) comes out to only around $60. Then again, the electronics and batteries are where the cost is at, so it's not saying much.

So, I got the parts in the mail today:

There's a film stuck onto the plastic. Peel it off, and you get beautiful clear plastic:

:D :D :D

Offline airman00

  • Contest Winner
  • Supreme Robot
  • ****
  • Posts: 3,650
  • Helpful? 21
    • - Mechatronics and related
Re: Laser cutting is awesome
« Reply #1 on: July 16, 2008, 01:34:42 PM »
an update!!!!!!

did you finish it yet?

and I'm looking forward for a tutorial detailing your work,

post up your CAD in your tutorial so that everyone can make the parts
Check out the Roboduino, Arduino-compatible board!


Offline ceruleanplains

  • Full Member
  • ***
  • Posts: 57
  • Helpful? 0
  • Got Wumpus?
    • Project Log
Re: Laser cutting is awesome
« Reply #2 on: July 18, 2008, 02:44:43 PM »
where did you get your parts from?

Offline emmannuel

  • Full Member
  • ***
  • Posts: 87
  • Helpful? 0
Re: Laser cutting is awesome
« Reply #3 on: July 18, 2008, 03:28:38 PM »
Nice, those are some sexy looking parts.

I'm surprised they'd send using such weak packaging. I figured the thin plastic parts could easily break in that package.

Offline GHFTopic starter

  • Jr. Member
  • **
  • Posts: 29
  • Helpful? 0
    • GeeksHaveFeelings
Re: Laser cutting is awesome
« Reply #4 on: July 19, 2008, 01:30:42 PM »
The plastic is actually pretty strong stuff. It's 1/8" PETG, which was quoted at 60%-70% the strength of polycarbonate. It's very similar to bottle plastic (PETE), so it's extremely flexible and can bend by a huge amount without whitening. It's not at all brittle like acrylic (Plexiglas), and can be drilled without crazing (cracking).

I don't know if I'll get around to doing the tutorial though. I'd like to defray the costs that went into it, but I don't really have the time, seeing as how I have to go to South Korea for a week on a (sort of) robot trip, and probably end up writing a research paper on something related to robots at some point. :D

Nevertheless, I'm still photographing the build as a sort of documentation. It's easier than taking notes.

Anyways, some photos, in approximate chronological order: :)

The inner frame to hold electronics and batteries. You might notice that's propped up at the bottom. This is because I made a mistake in the design. One of the perpendiculars has landing gears that are smaller than the landing gears on the other perpendicular. The cardboard I put the frame on is also curved for some reason.

The motor mount's holes actually match the motor's mounting holes perfectly, but I angled the screws outwards (you can see it in this photo) so I could get the nuts on more easily.

Now with all the hardware on the motor mount.

Put the motor mount on the carbon fiber and attach the rotor to the motor. :D

Soldered some nice connectors to the motor leads.

Working on the whole frame...

(Heh, high school student books) You can see a computer power supply unit, a battery charger, and a big 13.2V 2.3Ah LiFePO4 pack (delivers 70A of current :D). I'm going to use regular LiPos (7.4V, 1Ah to 2Ah) for the copter though.

Close-up shot.

I've been soldering this stupid 4-way split power cable for a hour. >:(

Soldering 16-gauge wire to the itty bitty pins on a Deans Micro connector is not fun. It's even worse when you realize your bought Chinese knockoff connects that melt under a soldering iron. Melt and burn. With smoke.

But, it looks so nice once I had finished. The motor controllers are hooked up to a 12V rail of a computer power supply with a Molex connector. That way I can power it for experiments without having to charge batteries.

There are more photos at The links here might eventually break if/when I decide to rename them or resize them.
« Last Edit: July 19, 2008, 01:35:04 PM by GHF »

Offline bens

  • Expert Roboticist
  • Supreme Robot
  • *****
  • Posts: 335
  • Helpful? 3
Re: Laser cutting is awesome
« Reply #5 on: July 21, 2008, 07:01:19 PM »
So...who cut your parts for you?

- Ben