…code, cg, electronics, 3d printing…

The main hurdle I’ve had with the Raspberry Pi is simply seeing the screen:  Since I don’t have  a spare monitor laying around, it’s plugged in over HDMI to my livingroom TV.  Sitting on my couch,… the text is really small.

Thanks to the awesome people at Adafruit Learning Systems, they’ve provided two tutorials specifically for logging into your Pi remotely over SSH (Secure SHell), and remote-controlling the desktop via VNC (Virtual Network Computing).  This gives you the advantage of not needing a spare monitor, keyboard & mouse to control the Pi:  You can use your current PC’s setup.

I don’t know anything about Linux or sysadmin work, but their tutorials worked exactly as shown and I was connected in no time.  I’m posting this mainly as a reminder to myself how I got all this stuff hooked up…

• First, you need to get a SSH connection from your computer (in my case, Macbook Air) to the Pi:  Adafruit’s Raspberry Pi Lesson 6: Using SSH shows you how.  Once this is setup, you can easily remotely login from a Terminal on your PC, and take control of the Pi.  But you don’t have access to it’s gui system, only the command-line.
• Second, to control the Pi’s gui, you need to install a VNC server on the Pi, and a client on your PC (Adafruit recomends RealVNC’s ‘VNC Viewer’).  Their tutorial covers all of this: Adafruit’s Raspberry Pi Lesson 7: Remote Control with VNC.

Once all that software is installed\setup\configured, how do you make the connection?

• Boot the Pi, wait for it to ‘be ready’.
• Open a terminal on your PC:  SSH into the pi (put in appropriate ifnet address of the Pi and login name):

• ssh 192.168.2.97 -l myPiLogin

• The terminal is now controlling the Pi.
• Next, start the VNC server on the Pi:

• vncserver :1

• Now that you have a SSH connection to the Pi, and the VNC server running on the Pi, you can connect via VNC Viewer on your PC:
• Open the VNC Viewer app, and connect to the pre-configured server you made earlier:   For example, 192.168.2.97:1
• After entering in the password, the Pi’s desktop should spring to existence on your PC.

Pi's desktop on my Mac's desktop: Success!

Last weekend I printed out this Makerbot Snowman for a ‘secret-Santa’ gift exchange:

All together took around 7 hours.  The next day I went to do another print.  But something was wrong.  The Heated Build Platform wasn’t ‘heating’… it was stuck on 14 degs.  Upon closer inspection I saw this:

(it was plugged in at the time, un-plugged for drama)

Fried.  Contacted Makerbot tech-support, and 5 days later I had a new wire & connector in-hand, no charge.  Plugged it all together:

And now it’s happily printing again.  It’s probably hard to tell from the pics, but the positive and negative leads on the new connector are a larger gauge:  Support said that the newer models ship with the larger wires, presumably because of these issues.

I thought it would be a good experiment to try 3d printing something ‘more complex’ on my Replicator:  Enter the “Botmobile”

• Assembly Instructions.
• Files on Thingiverse.

First off, some pics!

Here’s all the 3d parts printed out, plus the electronics kit… which is no longer available in the Makerbot Store:  I talked with Makerbot support, they’ve discontinued it

And here’s the finished thing:

It was quite a process to get everything printed out, but overall, really enjoyable and I didn’t encounter any problems.  I printed everything out in black ABS, and then spray-painted the body and wheels cherry-red (same as the previous bowl I printed).  The assembly went off without a hitch, and other than having to slightly adjust the front steering servo, it started driving right away.  Overall, I wouldn’t call it a ‘high performance’ RC vehicle:  Already the gearbox is starting to strip (and I can’t figure out why, it seemed pretty tight when assembled), and the front wheels hit the battery-box when turning sharp (underneath, in the middle) if you don’t trim it right.   But it does drive around and steer, so mission accomplished there.

Everyone’s been asking how long it took to print.  I’ve had little luck successfully using the ‘accelerated’ setting on my Replicator, so it’s all been ‘standard print times’.  There were multiple files to print, here’s the time estimates for each:

• Windshield: 1h 7 min
• Rear Axel: 1h 34 min
• Back half of body: 4h 51 min
• Front half of body: 5h 22 min
• Gearbox: 2h 21 min
• Interior seats: 2h 57 min
• Front steering assembly: 1h 44 min
• Wheels (all four): 8h 41 min

So that adds up to 28 hours 37 minutes.  It didn’t seem that long though:  Most of the long prints I did overnight:  I hooked up the printer to my a light timer (the type you plug your lights into when you go on vacation so you can turn them on\off at a certain time), and would set it to auto-turn off the printer about half hour after the print should finished.  Worked perfectly every time, didn’t have any misprints.

As of the time I printed it, I’m one of four people who have ‘made it’ on Thingiverse.  So it’s a unique feeling to know that… not many people on the planet have a 3d-printed RC car.  Here’s a few more pics: