Saturday, April 8, 2017

mowbot reboot

I'm working on rebuilding the mowbot.  One of the main problems with my previous design was that a lot of weight was placed on the front caster wheels, eventually causing them to fail.  My next iteration of the mowbot will position most of the weight over the rear drive wheels.  With less weight on the caster wheels (and perhaps sealed bearings?) they should last much longer.

The first step for the new frame is the motor mount plate.  I designed this in OpenSCAD, exported to Inkscape and finally printed on paper to use as a template.  A good friend allowed me to use his plasma cutter (thanks Chris!) to make this plate.  

Next I will start mocking up placement of the mower deck and batteries. 

Tuesday, April 19, 2016

AustinROV @ 360 Bridge

Check out our latest AustinROV adventure.  We saw fish!  Lots of things went wrong, some things went right, read more on the team blog.

Monday, April 18, 2016

TinyCore NAS on Raspberry Pi

One of the major drawbacks of the Raspberry Pi is that by default you are running the OS on an SDcard.  Eventually this turns into a corrupted SDcard where you lose the OS and everything you didn't back up.  One solution is to use BerryBoot and install the OS to a USB flash drive or HDD.

The TinyCore solution is to run the OS entirely in RAM.  This frees the SDcard from the barrage of reads/writes by the regular Raspbian system (or most other OSes) thus extending the lifetime of your project/OS/data/happiness.

Is it more reliable?  I don't know yet.  If it works for a year then I'd say yes it is indeed more reliable.  For now I'll just assume it is and hope for the best.

By the way the Raspberry Pi is a terrible NAS.  I was already aware of this.  Don't build something like this unless you already understand the limitations.  For my next NAS project, possibly many years down the road, I'd like to do something with gigabit ethernet and sata.

Here are the steps for installing and configuring your very own piCore NAS.

  1. Install piCore 6.1 to an sdcard and expand the filesystem. 
  2. Run tce-ab and install ntfs-3g.tcz and samba4.tcz.
  3. Configure networking
  4. Configure samba.


Friday, February 12, 2016

Goodbye dyn, hello google

DynDNS is kind of expensive if you pay them to manage DNS for you.  My DYN services were costing me about $45/year.  When it came time to renew this year, I shopped around and found Google to be much cheaper at ~$12/year.

Check into it if you own any domain names.  If you have a cheaper service, tell me who it is.

Monday, November 23, 2015

IOIOcar p1 oops boards for free

Due to a PCB manufacturing error I'm currently overstocked on IOIOcar p1 boards and I'm giving them away! That's right free! These boards work just fine for the IOIOcar functions, they just have an incorrect hole spacing in the prototyping area. If you pay for shipping then I will send you one PCB for free.

Consider these "limited edition" since I've designed a new board and won't be making any more like this. Leave a comment or get in touch if you're interested.

You will need the parts from the BOM to complete the board:

More details might be found on GitHub.

Here is a table showing the IOIO pins utilized.

IOIO PinIOIOcar Function
3UART RX (gps tx)
4UART TX (unused)
39Servo power relay
40ESC PWM output
41Servo PWM output

Get autopiloting!

Sunday, October 4, 2015

AustinROV: For real this time

AustinROV: For real this time: We took the ROV to the San Marcos River today at La Isla. This is sort of how it went, though it doesn't tell the whole story.

Monday, September 7, 2015

Introducing IOIOcar

Here are the beginnings of my entry for the Sparkfun AVC in 2016. My vehicle doesn't have a name yet and I am looking for suggestions. I'm releasing all of my source code and hardware designs to encourage openness and competition. Check out my github for the files. On the right you can see a picture of the electronics plate for mounting the brains to a Traxxas Rustler.

On the hardware side, I've developed a PCB that I call the IOIOcar. This is a board that connects Ytai's IOIO to a couple of servos and a relay. I'm using OSH Park to produce the PCBs and selling kits here.

The software is written in Java using Android Studio. The Android phone (or tablet?) provides many sensors and GPS which come in handy for navigation. Importing the "android" folder from github should be all that you need to do to get started.

I was planning on selling kits but nobody was interested.