While we maintained a presence at the IARC this year, we did not compete. The competition took place in Puerto Rico in July.
We will gradually upload notes from various presentations, conversations and observations. Feel free to discuss in the comments!
Notes from Michelson’s Opening Presentation:
Possible MAV missions:
1. Home into radars, swarms, disrupt air traffic
2. Home into radios and do damage, disrupt communications
3. Prime mission: underground facilities, something that flies in, sits in a powered down state and activates as needed, stealthy
Current Problems:
1. Scaling, not only Reynolds #, but also wavelength of communications frequencies
2. Indoor: communication problems and GPS problems. Navigation needs to be autonomous. Can’t have a high gain GPS antenna on a small scale. Similarly a scaled down com antenna won’t talk through walls.
Examples: Black widow, Mirador
3. Weight: Bulk of energy going to propulsion
4. Latency: eliminating teleoperation would eliminate a number of sources of latency
5. Energy
6. Aperture: Wide bandwidth video feed conflicts with high frequency to accommodate size of vehicle
Example: bump on global hawk is a satellite, aperture size of communications
7. Self Stability: Can assume cultural environment like vertical walks and horizontal roof, need a reference in absence of GPS, maintain starting memory
8. Avoidance: Reactive, Preplanned, random decisions to avoid getting stuck
Indoor Navigation without GPS
1. Ultrasonic system, own GPS system inside, before Novatel and other companies people didn’t know how easy GPS was and we became reliant on GPS thereafter
2. How do birds do it? Vision, Gravity, Range estimation (stereo vision), Acoustic cues, Airflow direction, Friendly or foe / potentially useful obstacle detection
Low Power Communications and Sensing in Spectrally Cluttered Environment
1. Noise Sources
2. Multipath
3. Near field spectral clutter, e.g. if trying to implement a radar, how do you interpret your reflections
4. Low power transmission @ high frequency
Indoor Fixed Wing
1. Not good
e.g. Aerovironment UAV – could get sucked into a vent, 90 s flight time, landing problems, can’t go so fast
2. If you can get 5 minutes inside a building you can cover a lot of rooms
3. If can land then can power down and maybe plant a sensor, mission can last weeks. E.g. land and wait for someone to turn on lights.
Tail Sitter MAVs for Indoor Flight
1. Efficiency not so great, some possibilities
Lighter Than Air
1. Toy blimps, but 15 cm is impractical: only 1.84 grams of lift
2. In a breeze it would act like a sail
3. Drag
Quadrotors
1. Many teams
2. Around for a while, 1923
Co-axial Helicopter
1. Better for indoor
2. Fly slowly
3. Highly controllable
Flapping Wing
1. Hard for controls
2. Everything in nature flaps wings except maple seeds?
e.g. Entomopter, Aerovironment Humming bird, CIA dragonfly
Conclusions:
1. Close proximity to obstacles
2. Spectrally cluttered multipath
3. No teleops, No GPS
4. flapping wing etc good
Stay tuned for more notes and videos!
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