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DRAGON - Technical Specification  - ver 1.0
================================

The dragonís technical specification has been grouped into the three following sections:
  Physical details, 
  Electrical and control details and 
  Anatomical breakdown. 
These give the overall physical sizes, mechanical, electrical and control equipment 
content, and the anatomical breakdown gives an indication of the location of all of 
the parts related to each other.

Physical details
----------------
  Scale  - Built to anthropomorphic scale, 
           lizards and Komodo dragons cover a wide range of sizes.

  Height - 150 mm

  Width	 - 290 mm span of the legs standing normally

  Length - 450 mm Head and body, (excluding non functional tail)

  Weight - 1.16 kg 

  Joints - 6 single axis    Servos  DoF
    Head left / right         1	     1
    Head up / down            1	     1
    Front legs in / out	      1      1
    Front legs rocking beam   1	     1
    Centre body pivot 	      1	     1
    Back legs in / out	      1	     1
    Rear legs rocking beam    1	     1
      Totals                  7	     7
   

  Bearings       - 2 sleeve bushes one per rocking beam

  Servos         - 7 (4  mini, 3 standard )

  Links          - 6

  Gear drives    - 1 at 1:3 (centre body pivot)

  Direct drives	 - none

  Dampers        - none


Electrical and control details
------------------------------

  Power supply
     1.0 Ah 7.2 volts Nickel Cadmium, 12 amp diode 10 amp relay main supply
     Voltage regulated supply 1 amp 5 volts

  Controllers
     Two Scenix SX28AC/DP  microcontrollers running at 8 MHz 
     The SX28AC processors are executing their programs at 8.88 MIPS, but this capacity
     is limited by the Stamp2SX which is executing code at 0.01 MIPS
     One Stamp2SX microcontroller module

  Sensors - seven analogue and digital inputs
     Right eye  - 1 off analogue input light sensors
     Left eye   - 1 off analogue input light sensors
     Front right foot contact switch
     Front left foot contact switch
     Back right foot contact switch
     Back left foot contact switch
     Battery voltage 

  Outputs
     Servo power relay
     Collimated red laser diode (nose mounted for vision )

  PCBs - three custom designed and fabricated PCBs

  Control electronics / processors
     control voltage regulation
     power management and battery voltage sensing			


Anatomical breakdown
--------------------

  Head	
    2 eyes  - single pixel light dependant resistor with focus lens
              set for convergence with laser output at 250 mm
    1 Laser - optical targeting
       	
  Body	
    3 servos
      Head pan and tilt
      2 x Ripmax SD200 Mini Servo - Torque: 2.5 kg/cm, Weight: 16 g
      Centre body pivot 
      Hitec HS-300 BB Servo - Torque: 3.5 kg/cm, Weight: 44.5 g

    2 Scenix SX28AC/DP  microcontrollers
    1 Stamp2SX microcontroller module
      System controls covering all functions
      Vision, input, output servo control and memory

    3 PCBs
      Electronics custom designed double sided,
      including power management 1 x 12 amp relay, power sensing, 5 volt 1 amp regulator

  Battery - 1.0 Ah 7.2 volt Nickel Cadmium

    1 switch - SPST power on/off
         
    1 charge socket

  Front right leg
      2 x 1/2 servos - Lower leg in / out, leg up / down
      Knee - 1/2 x Ripmax SD200 Mini Servo - Torque: 2.5 kg/cm, Weight: 16 g
      Rocking beam - 1/2 x Hitec HS-300 BB Servo - Torque: 3.5 kg/cm, Weight: 44.5 g
      1 switch - foot contact to floor

  Front left leg
      2 x 1/2 servos - Lower leg in / out, leg up / down
      Knee - 1/2 x Ripmax SD200 Mini Servo - Torque: 2.5 kg/cm, Weight: 16 g
      Rocking beam - 1/2 x Hitec HS-300 BB Servo - Torque: 3.5 kg/cm, Weight: 44.5 g
      1 switch - foot contact to floor

  Back right leg
      2 x 1/2 servos - Lower leg in / out, leg up / down
      Knee - 1/2 x Ripmax SD200 Mini Servo - Torque: 2.5 kg/cm, Weight: 16 g
      Rocking beam - 1/2 x Hitec HS-300 BB Servo - Torque: 3.5 kg/cm, Weight: 44.5 g
      1 switch - foot contact to floor

  Back left leg
      2 x 1/2 servos - Lower leg in / out, leg up / down
      Knee - 1/2 x Ripmax SD200 Mini Servo - Torque: 2.5 kg/cm, Weight: 16 g
      Rocking beam - 1/2 x Hitec HS-300 BB Servo - Torque: 3.5 kg/cm, Weight: 44.5 g
      1 switch - foot contact to floor