System

Elcano DIY robot kit

The Elcano Project is developing low-cost hardware and software kits to convert any vehicle to self-drive. We are concentrating on recumbent tricycles, since that produces a real people mover at a total cost of under $5000. Our kits could also be used in full-sized cars or toy RC cars.

The kits are based on Arduino microcontrollers, and allow you to connect them robustly into a compact, low power package. The basic package uses several processors:

  • C2 – Dual control: low level vehicle control, either from the driver or the AI.
  • C3 – Pilot: Detects obstacles and feeds settings for the next path segment to C2.
  • C4 – Path Planner: Computes the best route from current location to destination.
  • C5 – Reverse pilot (optional): May supplement C3 and C6.
  • C6 – Navigator: Reads GPS, INU, Odometer, Sonars, etc. to get best position estimate.
  • C7 – Vision: Locates certain features of interest.
  • C8 – Simulator interface: Replaces sensor inputs with outputs of PC simulator.

The control signals are documented on Wiring_C2PCB.xls for low-level and on Wiring_C6Trio.xls for high-level.  Processing is supported by a set of custom circuit boards:

  • MegaShieldDB – Plugs into C2 and brings out signals on robust cables, making the wheels spin and steer.
    Eagle Schematic /PDF;  Eagle Board / PDF
  • MegaShieldTrio – Houses C3, C4, C6, INU and GPS. It can also be configured to include C5.
    Eagle Schematic /PDF;  Eagle Board / PDF
  • Sonar – Houses five sonar range finders, covering 180 degrees.
    Eagle Schematic /PDF;  Eagle Board / PDF
  • MegaShieldSim – Houses C8 and connects to the MegaShieldTrio.
  • Panel – Operator status information and switches.
    Eagle Schematic /PDF;  Eagle Board / PDF
  • E-stop – Remote E-stop and joystick for operator control.
    Eagle Schematic /PDF;  Eagle Board / PDF

The heart of the system is the flexible MegaShieldTrio board. It includes a proto-board area and may be useful for any project based on three or four Arduinos. The standard configuration uses an Arduino Mega SDK for C6, and Arduino Nanos for C4 and C3. The Mega SDK is a USB host and will interface to an Android smart phone. Shields can be plugged into C6 and C4. The MegaShieldTrio has plugs for odometers and two sonar boards. Alternatively, the board accepts a Digilent Max 32 as C6. It can also be built to use an Arduino Uno for C6 and and an Arduino Nano for C5. The main communications link between processors is serial.

The C7 vision processor may be any suitable platform, and communicates with C6 over USB. It will also use USB to talk to a camera. The C7 processor could be quite extensive, and incorporate V2V, I2V, radar and Lidar. The system will work without any C7 processor.

A PC based simulator is under development. It will use USB to communicate with C8; C8 then generates all the sensor signals for the AI. These include a simulated video camera to C7. It also supplies the signals that would come from GPS, INU, Odometry and Sonars.

Architecture

Leave a Reply

Your email address will not be published. Required fields are marked *

Open Source Autonomy