Contributing to giving sight to AV's

Posted by RoboBill on December 16, 2014 at 9:02am

Hello everyone,

I'm trying to design and build an "open source" radar system. The premise is that while we have the hacked Neato and the RoboPeak system, I've not found anything for outdoor use. So I've built this scanner pictured below.

3691167470?profile=original

The parts list so far is

1) Hobbypower BGM5208-200T-12 HS Brushless Gimbal Motor

2) AlexMos 8 bit controller

3) Arduino Uno

4) Sparkfun Line follower (as a simple rotary encoder)

5) 12vdc power supply

The design criteria is that no special tools (lathe, mill, tap & die) are required. All parts shall be easily available from reputable sources. From this I hope more people will build one and begin to give real sight to their AV.

My question is how to best promote this project and share files like these two versions for the Lightware SF02 and Lidar Light units I made with Solidworks.

3691167506?profile=original3691167374?profile=original

I'm a real NOOB with Github and blogs, so any suggestions would be helpful.

Thanks

RoboBill

   

You need to be a member of diydrones to add comments!

Join diydrones

Email me when people reply –
Follow

Replies

    • Phill Scott > RoboBill January 9, 2015 at 9:55am

      Only passing power/ground through the slip ring would be a good idea.  I thought I could see you had a suppressor on the lines? perhaps they were different lines to the motor.  Had my LL confirmed as in the post and had a good chat with the guys I want to buy the NC machine through so I aim to go ahead with that.  Will be able to get going fairly soon.

      Another possibility if you wanted to go wireless could be an NFC card?

      This one does P2P transmission:

      http://www.seeedstudio.com/wiki/NFC_Shield_V2.0

    • RoboBill > Phill Scott January 9, 2015 at 1:25pm

      Hi Phill,

      I put a suppressor on both sides of the slip ring assembly. I'm now building the two arduinos with transceivers now. (I have these parts from a previous project). Will report back ASAP.  

      RoboBill

    • RoboBill > RoboBill January 13, 2015 at 9:06pm

      I've built the LL with Arduino/XBee to eliminate the slip ring noise. I'm not getting good readings outdoors. I think I need to tweak the LL settings and am awaiting help from the LL people.3702903448?profile=original

      RoboBill

    • RoboBill > Phill Scott January 9, 2015 at 6:42am

      Howdy Phil,

      I think its the measurement of the LL PWM signal that's the issue here. One possible fix .... mounting the Arduino on the upstream side of the slip ring. I believe this will work because I used both the analog and serial connection on the SF02 and it didn't appear to have any slip ring issues.

      I'll look at one of those mini Arduinos on Sparkfun.

      I will also follow your advice and put a suppressor around the gimbal motor wires.

      RoboBill

    • Phill Scott > RoboBill January 8, 2015 at 4:42pm

      What about noise from the motor?

      I wonder if you could hand crank it and see if you still get the odd readings with the gimbal power cables disconnected?

      If its not that, you could hand crank through 360 degrees and then back after removing the slip ring?

      The gimbal motor you are using has given me an idea - I'm waiting for the LL to turn up, and am seriously thinking of getting a table top NC router as they seem to be ideal for prototyping where 3D printers fall down - and it seems its easy to put a print head on the table anyway.  Then I can mess around with some ideas.

  • Phill Scott January 2, 2015 at 11:07am

    Ok Bill, I'll see what I can come up with.  Seems to me that we will be working the gimbal motor in exactly the opposite way to that intended by the gimbal control board.  So long as what the gimbal user wants is a defined angular velocity for the thing being stabilised (zero deg/s in most cases) then a.n.other angular velocity can work just as well.

    I've yet to find a suitable motor/servo solution.  As you say, annular shafts are hard to come by.  It seems a lot easier to use an offset motor and two cogs - then we can have whatever pass through size we want.  Not ideal for robustness but does make the problem go away.  Having said that, the baseplate might be of a size where the motor can be moved around without driving the baseplate size, and that may make the design more compact.

    • RoboBill > Phill Scott January 2, 2015 at 3:13pm

      Hi Phil,

      Check out ServoCity.com. They've got a lot of cool stuff that you might be able to use.  It all appears to be off the shelf so no machining necessary.

      RoboBill

    • RoboBill > RoboBill January 3, 2015 at 9:48am

      Here is a Process.org display of the Lightware SF02 outside. It was taken at about 8:30 AM. The sun is low being wintertime in the SF Bay Area. The sweep rate is 20 degrees per second.

      3702680995?profile=original

      welcome to the process...
    • Phill Scott > RoboBill January 3, 2015 at 10:17am

      How well do you think that represents the space you were in? The glass window reflection has given you a low range false reading? Do you think that there are any other false range readings?

    • RoboBill > Phill Scott January 3, 2015 at 12:09pm

      Hi Phil,

      I feel real good about the readings. The "out of range" on the left side was when the laser was pointing to a hillside 1/2 mile away. The glass window was reflecting the morning sun. So it too was a not read area. I later moved the scanner around a bit and it caught the profile of a circular sun lit brick wall perfectly. 

      I'm still having some problems with the rotary encoder and interrupts. My son will fix that next week.

      RoboBill

      BTW my dog is the bump just to the right of the building corner :-)

This reply was deleted.