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Logging sensor data: | Logging sensor data: | ||
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How many sensor reads per second to record? 10 should be enough | How many sensor reads per second to record? 10 should be enough | ||
Revision as of 23:41, 26 September 2006
Contents |
Microcontrollers
Arduino
- Arduino website - Specs.
- Buying info - $31.95
- Uses Atmel ATmega8 chip (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:
- Memory - we need an external 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
Interfacing an EEPROM - this one stores 64 Kb of memory.
We're also going to need to write code that reads from the EEPROM and uploads the data logs through the USB to the PC.
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
