The Robot - Progress and a Video

[ Thanks to Adam Palmer for this link. ]

"The motor controllers sometimes dropping/misinterpreting commands during heavy load was solved by a number of different fixes. Firstly, I believe with the USB to TTL converters the data lines are pulled up to 5v with a 4.7K resistor. I added a second 4.7K resistor in parallel to Tx to give the controller more of a chance against interference. I also added various smoothing capacitors, and edited my serial port byte transmit tool to restore the serial port settings graceefully on exit. Oh - I also cut the cables from their default 1m to the 12cm that I needed.. No more dropped commands.

"The wheels are better reinforced under the base to cope with the added weight and I have also balanced it out more by adding a 0.5kg metal cage to the opposite side to the battery. The metal cage houses a proper DC to DC adapter which takes about 7.5v-15v DC and converts to a clean 12V output."

Complete Story

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• The Robot: A Body, Sensors and Good Progress(Nov 15, 2008)
• The Robot: Successful Installation of Debian onto the Alix 3c2 Board(Nov 04, 2008)
• Linux Robot - Watch This Space(Oct 08, 2008)