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Tom by David Buckley July 2002
Tom is a three servo biped walking robot.
Following on from biped robot Junior I designed Tom, much taller than bigFoot and Junior and named after Detective Tom Polhaus. 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 and obstacle detectors on the toes. It was intended to fit IR sensor looking through the soles to detect table edges.

  • 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 the 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, 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.
  • 4 September 2017 - Software amended to have allophones in BS2e-2 and PicAxe40x controlled by cmnds
    "A" - report Act, and "S" - say allophone stream.
  • 19 September 2017 - added a TwinkleToe optical obstacle detectors on each toe.
  • 19 November 2020 - added a plugin PicAxe08m2 for receiving Sony IR commands.
  • Hardware
  • # Tom plans
  • 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.
  • PicAx08m2 on each toe for optical whisker for obstacle detection
  • plugin PicAx08m2 for receiving Sony IR commands.
  • Software
    For an overview of the software see the Ambler page.
  • Tom commands
  • Tom Ear commands
  • Tom14-0.BSe - Command interpreter
  • Tom14-1.BSe - movement
  • Tom14-2.BSe - talk + word_DATA
  • Tom14-3.BSe - Acts1_DATA
  • Tom14-4.BSe - Acts2_DATA
  • KasTomCortex-40x-v1.bas - control of SP0256 speech chip
  • KasTomToeP08m2.bas - TwinkleToe
  • KasTom_IRearP08m2-v2.bas - receive Sony IR commands
  • Tom Ear memory dump
  • BigFoot, Junior and Tom

    Tom at 5th December 2009

    13 September 2011 with a PicAxe 40x controlling an SP0256 speech chip (also with later IR ear)
    The PicAxe 40x also reads the Hex-switch (green) and reports to the BS2e the Act to execute.
    The two 2x5 pin headers were intended to interface IR obstacle detectors, however I wrote the Aesir software which uses a PicAxe 40x2 and is a much more capable system so left Tom's BS2e+40x system as it is.

    19 September 2017 - TwinkleToes, optical obstacle detectors

    19 November 2020 - IR ear for Sony IR commands

    Tom plans
    Squares are 5mm
    Toe Sensors
    Tom & Kas - circuit
    Tom & Kas - PicAxe40x + SP0256 speech chip

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