Wednesday, January 19, 2011

Hacking the OWI 535 Robotic Arm Edge 5 axis

I have started compiling information on ways to extend the OWI 535 Robot Arm. The general idea is not to turn the arm into anything unreasonable, just to get the most learning possible out of a nice, accessible kit.

So whats the todo list?

1) USB interface - Easy there are two commercial one availible which takes the effort out of it. Otherwise you can hack in a pic interface if you are keen.

Solution (3)
RAI-Pro USB interface kit

OWI USB Interface kit

2) Position sensing - Currently there is no useful position control built into the system ( or the commercial usb interface) So the arm drifts pretty badly when its under any load or the batteries start to fade... or really anytime.

Partial solution

3) Power system - Replace the batteries with some more reasonable power source to drive the motors at a more consistent rate.

Solution (?)

4) Better software Interface - Having the ability to code against a standard dll wrapper around the driver would be more useful than the current black box software. There is a driver "elanusb.sys" but I am still trying to work out how to interface with it.

The other option is to write a new USB driver for the system. Once I remember to look at the USB IO chip on the USB interface board I will hopefully be able to figure out what is capabilities are and hack up a driver for it. Should be fairly simple as there are only 5 axis and one light so it should be fairly much on/off for each axis with forward and backward, plus the light on/off. So I estimate there are about 12 commands possible. That's assuming the timing logic is not encoded into the IO chip; which seems unlikely.

Solution (?)


Another group of hackers on the same path

Data Sheet for the Main Elan USB chip (EM78M612DDMJ) here


  1. I am working on this. checkout the link to see a video of my progress.

  2. Any progress? What is the latest news?

  3. I have completed my modification program. See

  4. Brilliant. Reading your work with interest.