Wednesday, November 27, 2013

Robot, take out the trash!

Requirements | Design 1 | Design 2 | Chassis ]

I hate wheeling the trash to the curb on trash day and sometimes I forget. Screw that noise, man. A robot wouldn't mind, wouldn't forget and wouldn't care if it's freezing outside. I'm building Take Out The Trash Robot. TOTT Bot, for short. So there.

A few of the many Actobotics parts I'm evaluating
ServoCity was kind enough to send me a giant box of cool Actobotics parts to evaluate. Seriously. I'm like a kid on Christmas opening the coolest new lego-lincoln-erector-tinker-riviton-toy ever designed!

What the Isaac Asimov is Actobotics, you ask? Lots of cool parts. Precise parts. With drill holes in compatible locations. So, it's easier to prototype. Between the ball bearings, precision shafts and tubing, lightweight aluminum channel, gears, sprockets, chains, belts, and pulleys, not to mention ServoCity motors and giant servos I'm seriously giggling with glee here.

As it turns turns out, I've been wanting to build a trash robot for a few years now. After wondering "what am I going to do with all these parts?" for awhile, I decided the trash robot is the perfect project to see what the Actobotics platform can do for us robot-builders. It's going to take several weeks to build and I'm capturing it all here. Hope you'll tune in while I prototype, build, figure, calculate, screw up, fix, and all that joy. On to the problem statement...

Tuesday, November 26, 2013

Pololu Black Friday

Pololu is doing another Black Friday sale this year! Lots of great deals. (No affiliation, I just like Pololu). (Update: click here for deals from Sparkfun, GHI, Parallax and Bot Thoughts!)

Pololu Robotics and Electronics is having its biggest Black Friday sale yet, discounting hundreds of sensors, actuators, motor controllers, and other robot parts by 30% to 60% and offering an additional 11% to 15% off orders over $100! Buy one Zumo Robot and get one free, save on a 3pi Robot and get a free programmer, and take advantage of great deals on select Arduinos, Raspberry Pis, and mbeds. The first doorbuster deals go live Wednesday, November 27, and the sale runs through Cyber Monday (December 2). For details, visit

Sunday, November 24, 2013

Cyber Monday, New Products!

Announcing Bot Thoughts Cyber Monday discounts! Details here.

Thursday, November 21, 2013

Microchip PIC 24F, 10MSPS 16-bit ADC, 2x OPAMP, DAC

16-bit, 10 MSPS ADC, dual op amps and 2x10bit 1 MSPS DAC. In case you were wondering MSPS is Million Samples Per Second.

If you're not picking your jaw up off the floor then maybe some comparisons will help.

AVRs have 10-bit, 15 kSPS ADCs. That's kilo-Samples Per Second. Two orders of magnitude difference. The ARM NXP LPC1768 can do 10-bit conversions at 500kSPS. There are Kinetis ARMs that do over 800kSPS. The dsPIC33F has 10-bit, 1.1 MSPS converters which used to be impressive to me.

Oh, and 10 bits is ok, 12 bits is pretty good. But 16 bits is crazy resolution for an MCU. Usually more bits means slower sample rates. And yet...

Tuesday, November 19, 2013

Hacking a dual rail supply for HP204 oscillator


I built a custom power supply for my HP204 oscillator and cleanly modded screwed up, hacked things together, and eventually shoehorned it into the case.

Now why would I go and do all that? Read on...

Monday, November 18, 2013

Sparkfun AVC 2014 Announced

Sparkfun has announced the date and venue for the 2014 Autonomous Vehicle Competition. June 21st at the Boulder Reservoir. Details here.

Thursday, November 14, 2013

ATtiny Software Serial

ATtiny software serial transmit and receive, based the Arduino SoftwareSerial library, and around 1K compiled. That's what I've been working on. Why?

Spy photo :) of ultra compact eeZeeISP AVR programmer
I'm designing a low cost, really small AVR Programmer, that's why. It's based on an ATtiny84A and requires SPI which claims the USI peripheral, leaving no hardware serial.

Here are the details on TinySoftSerial.

Saturday, November 9, 2013

Robot Art

My best friend is an artist. His latest blog post features some of the robot head art he's been working on. His prices are reasonable so if you want one, let me know and I'll put you in touch.

Wednesday, November 6, 2013

JavaOne: Raspberry Pi Embedded Challenge

After a couple late night hours at JavaOne Java Embedded Challenge, Bruno and I had written a field sobriety tester on a Raspberry Pi using JavaFX and Java Embedded Suite. It's an example of how easy it is to build embedded solutions when all the hard work is already done for you :) Here's what we put together...

Friday, November 1, 2013

AVR Watchdog as Sleep Delay

Use the AVR Watchdog Timer as a sleep delay. Put your ATtiny / ATmega to sleep and the Watchdog Timer will wake it up after a specified interval.

oh no, it's the glowing, blinking eyes of a chupacabra!
This is the technique I used for my lost R/C airplane model alarm. I also used it last night for my Halloween glowing, blinky eyes. Here's how.