Difference between revisions of "Polycopters"
From Vague Hope Wiki
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* Barometer - least sensitive, probably best for high-flying vehicles. Needs to be kept away from the wash from the propellers. | * Barometer - least sensitive, probably best for high-flying vehicles. Needs to be kept away from the wash from the propellers. | ||
* Ultrasound sonar - very sensitive for low-level flight, but tops out at a few metres. | * Ultrasound sonar - very sensitive for low-level flight, but tops out at a few metres. | ||
| + | * IR laser - Pete suggested this on my blog, I'd have thought performance would degrade outdoors, waiting to hear back. He's probably the expert here. | ||
==Hardware required for behaviours== | ==Hardware required for behaviours== | ||
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* Outward-aimed sonar - required for Autonomy behaviour: dynamic avoid | * Outward-aimed sonar - required for Autonomy behaviour: dynamic avoid | ||
* Radar - required for Autonomy behavior: dynamic rendezvous (allows dynamic avoid too) | * Radar - required for Autonomy behavior: dynamic rendezvous (allows dynamic avoid too) | ||
| + | |||
| + | ==Geekspeak== | ||
| + | * AP/Autopilot - low-level control processing, e.g. correcting for tilt due to wind, keeping level for landing. Think "Pilot". | ||
| + | * Autonomy - high-level control processing, e.g. navigating to certain points, loitering. Think "Navigator". | ||
| + | * RF - radio frequency | ||
| + | * RTK / RTCM - Real Time Kinematic / something, read this: http://linux.die.net/man/5/rtcm-104 Very little chance we'll use either. | ||
Revision as of 14:15, 25 January 2011
Contents
Background reading
- http://vicacopter.com/vika1.php (via http://hackaday.com/2011/01/17/tri-rotor-helicopter-with-full-autopilot/)
- http://aeroquad.com
Hardware choices
CPU
- Android phone - free GPS/gyro/cam/Wifi, but long boot time - even with a separate watchdog, crashed phone = crashed copter. Still need to break out an interface to motor control board.
- Arduino 2009 / UNO - nice hardware as has A+D I/O built in + neat shields for motor control. GPS/gyro/cam/control method will still need to be worked out. Memory space too limited for full autonomy?
- Arduino Mega - as above, more expensive but more memory, enough for full auto?
Altitude sensor
- Barometer - least sensitive, probably best for high-flying vehicles. Needs to be kept away from the wash from the propellers.
- Ultrasound sonar - very sensitive for low-level flight, but tops out at a few metres.
- IR laser - Pete suggested this on my blog, I'd have thought performance would degrade outdoors, waiting to hear back. He's probably the expert here.
Hardware required for behaviours
"What do we need to have in order to do x", in increasing level of unlikelihood that our vehicle has it:
- 3 axis Gyro - required for AP behaviours: takeoff, land, hover, up, down, move wrt vehicle orientation, pitch, roll
- 2/3 axis magnetometer/accelerometer - required for AP behaviours: move wrt north; local time-based autonomy behaviours (think LOGO)
- Barometer / ground-aimed sonar - required for AP behaviours: set altitude
- GPS - required for all outdoor location-based Autonomy behaviours, accuracy ~10m
- Multi-band RF receiver - required for all indoor location-based Autonomy behaviours (triangulation)
- Heading unit - negates need for magnetometer if in GPS coverage
- RTK GPS - improves position accuracy in heavy GPS coverage to ~1m
- RTCM GPS - improves relative position accuracy while in communication with static base station to ~1cm
- Outward-aimed sonar - required for Autonomy behaviour: dynamic avoid
- Radar - required for Autonomy behavior: dynamic rendezvous (allows dynamic avoid too)
Geekspeak
- AP/Autopilot - low-level control processing, e.g. correcting for tilt due to wind, keeping level for landing. Think "Pilot".
- Autonomy - high-level control processing, e.g. navigating to certain points, loitering. Think "Navigator".
- RF - radio frequency
- RTK / RTCM - Real Time Kinematic / something, read this: http://linux.die.net/man/5/rtcm-104 Very little chance we'll use either.
