In March 2023 I dragged the dilapidated Liberator remains out from under the Laser-Cutter and decided to refurbish it.

  Base size             20" x 15" x 10" to top of Skirt
  Rear Track            13 1/2"     => 3mm wheel travel per degree when turning on the spot
  Front track (nominal) 10"
  Wheelbase             9 1/4" forwards, 13" in reverse
  Castor radius         1 7/8"
  Rear wheels           6 1/4" dia.  => 499mm circumference ~> 500mm
  Drive
    10 tooth XL on gearbox
    60 tooth XL on drive wheel
    72 tooth belt 1/4" wide
    free running 120 rpm   => max speed 1m/sec
    free running ~3/4 amp, heavy load 3 amp, moderate load 1 - 2 amp
  Wheel encoder
    80 tooth MXL on wheel
    32 tooth MXL on encoder     (not yet refitted)
    => 200mm per encoder revolution 

  Motor/gearbox from Maplin 12v Auto Polisher, 
    output shaft held in chassis mounted dual ball race
  Front castors from abandoned Supermarket trolley
  Chassis and Skirt plates - wood

• I stripped it all down, cleaned it and resprayed everything;
• replaced the missing wiring in the Skirt plates;
• added witness LEDs activated by the Skirt microswitches, they are also under computer control;
• replaced the missing foam padding round the edges of the Skirt plates;
• remade the two side IIC boards with an added PCF8591 4 channel A/D convertor to read the IR whiskers (not yet made);
• made a similar IIC board for the rear Skirt plate;
• remade the power distribution for the base;
• remade the electronics shelf and fitted two motor driver modules which were spare from when I originally made Liberator.
• made a housing for the Base Ultrasonic Array.
• refitted the upper and lower body complete with their Ultrasonic Arrays.