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Kasper by David Buckley November 2003
  • Kasper Gallery
  • Amblers
  • Kasper is a three servo Biped Walking Robot.
    After Loki I decided to return to an Ambler sized biped robot with three servos like Tom. Named Kasper after Kasper Gutman because the third servo made it look quite fat.

    Kasper is identical to Tom except for the skeleton and the Ultrasonic sensor and 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.


  • November 2003 - Designed and made.
  • 14 June 2004 - fitted with Ambler BrainBoard v2 using a BS2e. Software Mom5.BS2 converted to Kas5.BSe.
    Toe boards added with wire loop bump switches, holes for downward IR-hole-sensors.
  • 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 Kasper'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
  • # Kasper plans
  • height 10 inch (25cm) overall, 8.5 inch (21.5cm) 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.
  • Kasper commands
  • Kasper Ear commands
  • Kas14-0.BSe - Command interpreter
  • Kas14-1.BSe - movement
  • Kas14-2.BSe - talk + word_DATA
  • Kas14-3.BSe - Acts1_DATA
  • Kas14-4.BSe - Acts2_DATA
  • KasTomCortex-40x-v1.bas - control of SP0256 speech chip
  • KasTomToeP08m2.bas - TwinkleToe
  • KasTom_IRearP08m2-v2.bas - receive Sony IR commands
  • Kasper Ear memory dump
  • Photos
  • Kasper Gallery
  • Kasper plans
    Squares are 5mm

    Toe Sensors
    Tom & Kas - circuit
    Tom & Kas - PicAxe40x + SP0256 speech chip

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