From Hovercraft

Revision as of 22:26, 26 September 2006

Microcontrollers

Arduino

Arduino website. Buying info - $31.95 Uses Atmel ATmega8 chip (Specs) More specs

Pros:

• USB connection
• Nice IDE
• Good documentation/reference with examples

Connecting sensors:

• Ultrasound: http://www.arduino.cc/en/Tutorial/UltrasoundSensor
• Accelerometer: http://www.arduino.cc/en/Tutorial/AccelerometerMemsic2125

Powering board:

• Takes 9-12V DC input - use a 9V battery

Powering fans:

• Need an H-bridge and 9V battery per fan

From Wikipedia "H-bridge" entry: "An H-bridge is an electronic circuit which enables DC electric motors to be run forwards or backwards. These circuits are often used in robotics. H-bridges are available as integrated circuits, or can be built from separate components."

Basically, they allow us to use an external power source (another 9V battery) to supply the power to the fan.

Logging sensor data:

• Bus memory circuit - we need an EEPROM

How many sensor reads per second to record? 10 should be enough Maximum logging time on the course as per project requirements is 10 minutes. 600 seconds * 10 reads/second = 6000 values Let's say a value ranges from 0-1024, e.g. 10 bits. 6000*10 = 60000 bits total. 60000/8 = 7500 bytes. 7500 bytes * 3 sensors = 22500 bytes = 22.5 kbytes

256Kb of memory should easily satisfy that requirement.

HoverSim

HoverSim is a simulation application designed as a testbed for hovercraft control techniques.

External Links

• "Design and Implementation of an Open

Loop Hovercraft Controller: Final Report" - http://web.mit.edu/danburns/www/resources/hovercraft.pdf