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The USB2AX is a small interface to control Dynamixel servomotors like the AX-12 from a computer. It plugs into a USB port and has a 3-pin Dynamixel connector to be connected to the servos.
If you're in a hurry, jump to Quickstart !
Status LED: the LED lights up GREEN when the USB2AX is ready, RED if not (no driver, USB authentication error…).
The pads and jumper under the PCB are detailed in the GPIO and SPI page.
The USB2AX is a direct way to control servos to move legs, arms or claws in a robot with an embedded computer (laptop or Raspberry PI for example).
You can also use it as a tool to setup, diagnose or fix your servos.
Have a look at some examples of application!
The USB2AX can talk with the Dynamixel servos which use a half-duplex TTL interface (3-pins connector).
More specifically:
Fortunately, the USB2AX can not do everything
Read the Quickstart Guide, and be on your way
More information for everyone:
Some more stuff for power-users:
Advanced topics to use the full potential of the hardware for your specific application!
First prototypes,
v1.0,
v3.0a,
v3.0b,
USB2AX Mini,
v3.1a.
v2 never saw the light of day, it was very similar to v1 and scraped when I realized it was going to be much bigger than v1. Instead, I went on with v3 that used smaller components (0402 passives instead of 0603, QFN instead of QFP for the ATmega).
And finally the commercial v3.1a, which differs from the original v3.1a only by its corners: they were rounded, they are now square for manufacturing reasons.
Xachikoma by Xevel, the four-legged reason for creating the USB2AX. 4 legs, 5DOF each, plus powered wheels instead of feet.
Charlotte by KevinO, an hexapod controlled with a Raspberry Pi through an USB2AX.
HexaWheels by Siempre Aprendiendo, an hexapod with wheels and a Raspberry Pi.
Grinder by Nick Donaldson of http://gotrobots.com, a big hexapod using MX-28T and one USB2AX, and with free wheels to move like the Roller-Walker!
Xevelabs, Xevel's blog.
Fourwalledcubicle, Dean Camera's blog.
PoBot (FR), a review by the French robotics association PoBot.
Seeedstudio, the manufacturer of the USB2AX v3.0a.
Contributors:
Nicolas Saugnier (Xevel) - Idea, original schematics, firmware, and everything else starting at v3.0.
Julien Le Guen (JLG) - Eagle schematics and routing of first versions.
Richard Ibbotson (iBot) - optimization of the code for lower latency, improvements to the schematics, implementation of advanced functionalities.
Thanks:
Dean Camera for making the greatest USB library for AVR, LUFA.
Weston T. Schmidt for making the cross-platform app DFU-Programmer!
Trossen Robotics, Robosavvy, SeeedStudio and Adafruit for the help (direct or indirect) to bring the USB2AX to market.
Inspirations:
Arbotix RoboController
Arduino Uno
Adafruit ATmega32u4 Breakout Board
Ruggeduino, for over-voltage protection on DATA