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Tom by David Buckley July 2002
For biped robot Tom I decided to put the tilt rods at the back so if I ever put arms on then the rods wouldn't get in the way. Tom was tested with a Toddler control board and it turned out the 18swg piano wire rods were a little weak and I had to stiffen them before Tom would walk properly. The extra height of Tom and weight of the three servos means the 4mm plywood flexes at the wrong time and the speed and range of movements needs to be limited for smooth walking.

Tom is fitted with three GWS SO3 standard size servos and has bump switches on the toes. It was intended to fit IR sensor looking through the soles to detect table edges.

History
  • July 2002 - Designed and made. Tested with a Toddler control board
  • 14 June 2004 - fitted with Ambler BrainBoard v2 using a BS2e. Software Mom5.BS2 converted to Tom5.BSe.
    Toe boards added with wire loop bump switches, holes for downward IR-hole-sensors.
  • 2008 - stiffened Tilt rods using channel from an umbrella someone had thrown into my garden.
  • Summer 2009 - 9v battery for ElectronicsPower replaced with 2AA cells in series with ServoPower.
    On Condor Using Ultrasonic sensors drained the 9v battery quite quickly.
  • 13 September 2011 - removed the breadboard and fitted a PCB with a PicAxe 40x controlling an SP0256 speech chip and with the intent of using the 40x to read IRwhiskers.
  • 3 September 2015 - using a combined battery for servos and electronics always caused noise breakthrough on the speech output. So I removed the extra two AA cells and fitted a 9v boost regulator to power the electronics so now there is no noise breakthrough. I also fitted a 1.3mm coax socket for external 5v power when testing. The boost regulator is lighter than the two AA cells removed and the difference made a considerable improvement in Tom's walking.
  • Hardware
  • height 11.5 inch (29cm) overall, 10.5 inch (26.7cm) to top of head plate.
  • three GWS SO3 standard size servos, Tilt, Stride, FootSplay.
  • Ambler Brain Board v2 using a BS2e.
  • 2 AA cells on each foot connected in series on the BrainBoard to power the servos
  • 1 9v battery in body for electronics power.
  • 2 AA cells in body wired in series with ServoPower for ElectronicsPower.
  • second PCB with an SP0256 speech chip and a PicAxe 40x to control it.
  • BigFoot, Junior and Tom


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