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1
Logic layer
Poll for sensor state
Send motion direction commands
Return polled state also do interrupts in
immergency situations
Sensors layer
Sensors checking suspension, fuel or battery
state, engine state etc.
Mechanical layer
2
Logic layer

• Have separate electrical layer next to
  mechanical one?

Separate electronics from engine and power
architecture (can exchange the electric motor for
a small combustion motor in the future)
- would need extra team for the electrical layer
Solution? Still have 3 teams separate power
architectures for the motor and for the
electronics (sensors/logic) part (2 subcomponents)
3
Logic layer
Electrical power architecture for Logic and
Sensors
Sensors layer
Possibly recharge using engines power
Engine its power architecture (electrical or
combustion or whatever)
Mechanical layer
4
Mechanical layer
See the Mechanics teams material on the web
http//www.mech.upatras.gr/robgroup/teams/mechani
cs/index.html
5
Sensors layer

• Define sensor classes
• Find info about available sensors order them
  in classes
• Design a plug play architecture for sensors
• Possibly design build some custom sensors

See the Sensors teams material on the web
http//www.mech.upatras.gr/robgroup/teams/sensors
/index.html
6
Logic layer

• Implement microcontroller logic for detecting
  available sensors (getting an id their class)
  and talking to them, plus receiving interrupts in
  special (immergency) cases
• Implement logic and architecture for wired
  and/or wireless communication with an external
  logic module (for example a Personal Computer)
• Design implement path-planning algorithms on
  the external logic module

See the Logic teams material on the web
http//www.mech.upatras.gr/robgroup/teams/logic/i
ndex.html
7
Wireless communication

• Bluetooth
• - too expensive for cheap/amateur projects
• - quite complex space setting, arround 10m range
• - many devices in the same space cause problems
• discovery architecture, ready-made modules
  implementing all the needed protocols (plus
  video/voice codecs etc.)
• Other standards
• - steep learning curve
• - expensive implementation of not needed features

8

• Suggested solution for wireless communication
• use Radiometrix (http//www.radiometrix.co.uk)
  chips
• transceiver (BiM2)
• long range (100m)
• low cost (1-10 pieces 31.78 euros academic
  price)
• communication controller (RPC)
• contains hardware logic to connect to PC via
  parallel port (printer)
• carries BiM2 on it
• - implement Aloha or similar Multiple-Access
  protocol for many robots/base(s) sharing a radio
  frequency channel

9

• Cant use FDMA (Frequency-Division-Multiple-Acces
  s) cause we cant grab many frequencies, one for
  each communication link (government doesnt allow
  it, plus theres a limited number of available
  radio frequencies)

• Aloha logic similar to radio taxis one
• originally designed implemented at the
  university of Hawai to link university
  departments scattered among various islands
• logic is
• 1) listen silence for silence
• 2) if no one transmits, wait a while (random),
  then transmit (add signature to where you are
  sending data, possibly encrypt too)
• 3) When finished sleep for a while (random), then
  go back to (1)