MARCY 3 REVEALED
There's the current Marcy 3 plan. Unfortunately not enough space to build her. Basically install a fuselage aroundVika 1. It's obsolete but it was the real Major Marcy's plane & we canuse the tail fins as landing gear. No-one knows if She actually flewone or if She just managed it.
The idea with this is to have panels which bolt onto carbon fiber rodsso she can fly with or without the fuselage. To speed up yaw response,the aft propeller tilts inside its shroud without actually moving theshroud. The aft shroud is probably going to be permanently tilted tosome neutral angle & probably tall enough to cover the propeller atnormal angles.
Forward landing gear is removable for hand launches but notretractable. There's a dome under the nose with a slit for a point &shoot camera to tilt inside of but not pan. Dome has to be strongenough to land on.
Propellers are 12x6 which makes the shroud inner diameter 13". Wings & fuselage between the wings & tail are variable length, probably made of removable sections. Aft fins contain CF rods & are used as landing
The exact dimensions are a long way from being known. The more rent increases, the smaller she gets. May use aluminum angle rods because
MARCY 2 REVEALED
The next indoor sonar demonstrator, since the monocopter ended up too big & unstable.
Swapped Vika 2's flight computer & shrunk her to the smallest possiblesize to make Marcy 2. She's the smallest vehicle we can make economically. A smaller vehicle using Feigau motors like theParrot demo would be more expensive so it's cheaper to bury our 1 Feigauthan buy 2 more to make a tri rotor. Turnigy/Towerpro 2410-9's are thelow point in motor prices when they're in stock.
Time to get rid of our 3 year old IDG300's. They had troubleinitializing on 1 axis. The pair could still be used in a flat IMU buttheir temperature sensitivity was horrible. Nowadays it's not worthhoarding gyros. They were free samples at a time no-one ever heard ofUAV's. Invensense thought their only use was phone cameras but we knewbetter.
Time to use up the LISY300AL's we got last April in a cube IMU.
MARCY 1 RADIO DISASTERS
The Marcy 1 ground station is basically a scratch built USB radio with 2 channels & a 224khz soundcard, sending 1.8Mbits of telemetry & sonar tothe laptop & 9600bits of commands to the aircraft.
Radio failures explain some of her instability. The Marcy 1 radios havenever performed as well in the fully integrated ground station as theydid in this test:
They sometimes work & sometimes drop out for no reason. There seems tobe no difference between straight dipoles, impedance matching baluns,plastic enclosures, bare circuit boards, low baud rates, isolatingcapacitors, & choke inductors for Vbus.
These radio parameters improved on the reference software.
Set the AFC range to +15/-16 Fres.
Use the highest receive bandwidth.
Use the highest FSK deviation.
The choke inductor on Vbus got rid of a lot of sonar noise.
Stepped up the remote control to 115000 baud but the flight computeronly has enough horsepower for 86000 baud. Now it's coming down tointerference from through hole parts.
She didn't crash there. It's a radio test.
New 900Mhz -> PCM receiver with a balun.
Without wind & with perfect radio contact she can hover in a smallarea. Cyclic effectiveness ramps up with very small magnitude & seemsto decrease with higher magnitude until she falls out of the sky.
Finally ran a stabilization pass on some Steve Morris helmet cam footage to see if it did any good for helmet cam footage. It looks a bit more like flying than clinging to someone's head but he needs a TASE gimbal & a head tracker.