Thursday, April 30, 2009

Robot Nao

Robot Nao is based on a 500 MHz AMD Geode CPU running Linux and implementing dsPIC Microcontrollers for motor control. Programmable in C, C++, Urbi and Python. Ethernet (in the back of the head) and WiFi are supported on board.

High level control and simulation via Aldebaran Choregraphe, Microsoft Robotics Studio, and other software.

For more information check out their website.

Tuesday, April 28, 2009

Cool Tool: Johnson Bar

The Johnson Bar or J-Bar is probably my favorite tool ever, it has been said that its mother was a hand truck and that its father was a lever. The Johnson Bar provides both a lever and a fulcrum in a convenient wheelie package. I suggest the 7 foot length for maximum leverage.

You can buy yours now at McMaster-Carr for around $130.

Monday, April 27, 2009

Reference Designator

R is for Resistor
C is for Capacitor
L is for Inductor
D is for Diode
F is for Fuse
Y is for Crystal... Wait, what!?

In another case of not being able to google find something if you don't know what it is called; if you are trying to figure out if Q3 is a transistor or a diode or an IC, then you need to look at its reference designator.

Friday, April 24, 2009


Upside: No Homework
Downside: No Credit

Wednesday, April 22, 2009

Waterproof IP68 Ethernet Cable

This looks like it would be useful when you need to connect your waterproof ground robot or AUV to the network for upgrades. There is no retention clip on the waterproof side, it is held in by the screw cover. I may end up using this one as a cisco style serial port.

A Revolution Technology of 9V Battery

This is definitely a revolution technology

This battery provides a drop in replacement for a regular 9 Volt battery and only weighs 23 grams when empty.

One downside however is that lithium polymer batteries are slightly temperamental. If the batter puffs up or appears bloated you should stop charging and properly recycle the battery as it is dead. You should only use a charger designed for lithium Polymer batteries, and preferably one with a built in cell balancer.

These cells are bloated and are now a fire hazard as lithium tends to react violently with air.

So each cell in the battery provides 3.7V and 380mAh but somehow the battery provides 9V and 450mAh. This is the power of Revolution Technology!

Actual specs are closer 8.4V peak voltage and 380mAh. I think the revolution has problems accurately rounding. On the upside your microcontroller's voltage regulator won't care that it is not getting 9 Volts.

Q1 appears to be a AO8822 Common-Drain Dual N-Channel Enhancement Mode Field Effect Transistor made by Alpha & Omega Semiconductor.

U1 has 6 pins and is labeled with part code PAL.

This particular battery seems to have died due to a short between pin 1 and pin 2,3. Sparkfun is awesome and sent me out a replacement with any hassles.

Wednesday, April 15, 2009

More Draganflyer X6 video

Friday, April 10, 2009

Self-locking latch mechanism

Here is an animation made in Pro/E for a latch mechanism that could be used for robotic payload delivery and retrieval.

Thursday, April 9, 2009

Infravision: Test Image Output

Unfortunatly the camera spacing seems a bit off for the focal distance.

The next step is getting streaming video working.

If you already have 3D glasses, Schillr is a collection of Stereophotography tools and images.

Software Version Control

Here is a nice SVN Cheat Sheet

Wednesday, April 8, 2009

Glue Logic

If you need a few NAND and NOR gates but don't need a full FPGA or CPLD, take a look at GALs which are the modern version of PALs and PLAs

This tutorial looks like a good introduction to GALs and this tutorial by Kenneth Maxxon explains how to use CPLDs.

Tuesday, April 7, 2009

Arduino Stacking Headers

I tried using wire wrap receptacles for an Arduino daughterboard and found that the insertion force was way too high for reliable usage. The alternative I found is Samtech Part numbers ESQ-108-14-T-S and ESQ-106-14-T-S. Unfortunately, only Arrow seems to stock them. Perhaps I'll carry them when I get the online store up and running.

These connectors work much better then the wirewrap sockets.

Old Robot Arms