No match for North Korea's 7 missile salute, but we tried.All flights have to take off pointing North & turn into the wind because of the 3DOF IMU. Managed to pull off some stiff wind without blowing string into the propellers. Forget about underslung payloads unless everything from takeoff to landing is automated.
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After spending 3 hours waiting for web pages to load, VicaCopter 4 is finally available for download. If U ever succeeded in building your own VicaCopter, U still probably wouldn't know half of what she can do.The idea with VicaCopter is to have a reference design that works but not to have you copy it exactly. It's mainly our own personal reference.It's amazing after all these years, VicaCopter is still the only English language source code for a fully functional helicopter autopilot that you can download without paying for. There is no support or warranty.Vicacopter uses a ground computer for flight control. An airborne microcontroller handles rate damping, PWM, & sensor capturing. The ground computer handles navigation & provides a simple instrument panel. Because you need a radio modem & ground station either way, it's the cheapest way to fly.VicaCopter supports 2 configurations:3 gyros & a sonar transducer for the minimal autopilot.6 DOF IMU, magnetometer, barometer, GPS for the full autopilotSome things VicaCopter can do:Can fly with under $100 of parts including a complete sonar positioning system.Automated landing & takeoffSonar position sensing for indoor flightGPS position sensing for outdoor flightGround station instrument panelUntethered communication from pilot to ground stationFully autonomous missions written in picoC scripting languageManual altitude & position changes from stick commandsCurved or linear pathsTurning towards a pointCamera trigger
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Integrated picoc as a runtime thread in VicaCopter. The current version locks up, it doesn't do floating point, it crashes your entire autopilot when it encounters an internal error, but after working around all the problems, managed to get some nifty flights out of it.It's like turtle graphics with a very very expensive turtle. U can build up incredibly complex flights out of reusable maneuvers. U can repeat maneuvers. U can nest maneuvers in maneuvers.Ironically, picoc was written to fly airplanes but its author never flew it in an airplane. His only application was that Surveyor rover.The lack of floating point means we can only do relative waypoints & no latitude & longitude.
That was a 15m altitude change & 2 pirouettes in picoc.
That was the cross mission & 2 circuits in picoc.
That was 4 orbits with the nose pointing in different directions in picoc. Impossible with tables of waypoints.It locks up if you forget a comma in an argument list. Don't use "assert" in programs which are intended to fly things. Run it in a thread so if it locks up, it doesn't crash you. A floating point trig library would be nice.
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Posted by Jack Crossfire on February 13, 2009 at 12:30am
These are basically 300ft XBee's for $10. They have no UART, only SPI. They don't have the GPIO functions of XBee's. They're the same size as XBee's. The idea is to bring the data processing of a really powerful computer on the ground to ever smaller, cheaper aircraft with these high speed radios.MicrochipHopefully Microchip is following the Sparkfun model of selling prototyped versions of its chips & not running short batches for reference designs.
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2 months after VicaCopter 2.0, it's VicaCopter 3.0. The autopilot has been moved to quad rotors. All control is done by VicaCopter. Just get 4 motors, 4 ESC's, 4 propellers, & fly. The quad rotor is the cheapest & easiest route to the air.A UAV programming language has replaced the table of waypoints to enable more complicated maneuvers. Automated takeoffs & landings, curved paths, pirouettes, turning towards a point are supported.Go to Vicacopter.com & build it.
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Posted by Jack Crossfire on November 21, 2008 at 10:30am
That's some extreme autonomous navigation. Forget about asking The Goog how it works or why anyone would bother launching a rocket sideways. We can only guess the 90 deg turn is to save space. There are probably some 1000000 deg/sec gyros in there. Maybe it's Attopilot 1.9.
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Decided to put VicaCopter 2.0 on vicacopter.com. This is the last version for single rotor copters. It's mainly a reference, since no-one will probably ever replicate it.This version uses ground based autopilot & has the most detailed schematics of them all. Embedded computers were never cheap & never provided enough computing power. The high cost of sub micro servos, rapid servo wear, difficult payload mounting, & tail rotor effects were counting down the T-Rex clock. A steep drop in brushless motor prices & a servo death & it's quad rotors over T-Rexes.
Everyone knows Air Busses have problems, from the 2001 crash due to rudder failure to the 1988 takeoff crash on GooTube, so no surprise that the latest sudden 650ft descent of an aircraft was an Air Bus whose IMU malfunctioned & sent out an erratic orientation.What a thrill that our home made IMU & autopilot can be at least as reliable as the world's largest, low bidding, government subsidized passenger airline manufacturer's. Our IMU has drifted from vibration but never suddenly disconnected or generated noise in flight.http://www.abc.net.au/news/stories/2008/10/14/2391134.htm
Spring mounted mass accelerometers truly do suck. Thermal accelerometers were once the standard & they're coming back now that everyone knows what high frequency vibration does to spring mounted masses.It's China to the rescue again, as the thermal accelerometers from Memsic are being used in thousands of persistence of vision wands at the olympics. The wands can display any communist party approved message when waved by manual labor. There are no pictures of the wands except for the thousands of blue dots in stadium wide shots. It must be an election year.Read more…
XBee Pros have been raised from $32 to $36. Feel like a fool for not buying more at $32, although the direct store still has some. Still have 2 $32 modules from last year. The higher priced model is the XBee ZB ZigBee PRO Series 2 supporting "more dense mesh networks". Maybe it even has Techron to clean your speed controller.In 5 years these obsolete modules will be $65. Should buy some paperclips. The next bull market is paperclips I tell U.The good news is a new 900Mhz module has appeared in the XBee form factor & all the way down to $75. Instead of upgrading those obsolete 2.4Ghz cameras to 900Mhz, could get 900Mhz XBee's for data & save a ton of money.
uBlox 5 is an enabling technology as far as navigation is concerned. We're going to see amazing things in cheap autonomous rotorcraft because of it. Optical flow may actually be knocked out by uBlox5 & the former complexity required to damp velocities is gone.Have 2 videos of the uBlox 5 controlling position in the wind. This is of course, totally electronic stabilization without flybar.
Another first from the "don't apply if your resume doesn't say MIT on it" department. The Eurocopter may have been the first to summit Everest, Alan Szebo Sr/Jr may rule the 3D kingdom, but the Hummingbird's got the endurance record now.http://www.darpa.mil/body/news/2008/A160DARPAReleasev4.pdfNow if only the Hummingbird could repeat these stunts without crashing.
It was the simplest, cheapest UAV possible: a magnet. It couldn't fly very high, it couldn't follow waypoints, it couldn't carry much of a payload, it was even more unstable than a helicopter, but it could fly as long as PG&E didn't have a rolling blackout.The guidance system was as simple as can be. Just pulse the throttle when too low or high. Scale the duty cycle based on the time between boundary conditions for lead compensation. A side magnet could move it sideways.Later on, discovered wings. Wings had huge advantages over a magnet.But, after the spare parts consumed $500 of rent doing nothing, decided there would be no other use for them & it was time to rebuild the magnet UAV. The hall effect sensor no longer works. It'll take some time to track one of those down.
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Have beaten the light painting algorithm to death. These are movies of some words being painted by autopilot. The 35mm sensor captures the entire flight from underneath. Then the flight recording is shown in Google Earth.Painting text in this confined space is the hardest thing the computer does. It requires a third entry in our gain schedule for velocity.P=1.0 Vmax=2m/s satisfy radius=2m for painting textP=1.0 Vmax=1m/s satisfy radius=5m for hoveringP=100 Vmax=4m/s satisfy radius=5m for forward flight. Light painting VIKA from heroine worshipper on Vimeo. Light painting LION from heroine worshipper on Vimeo.These are the still photos.
Ning is the only game in town for 13megapixel photo downloads. Right click & view image to get the Ning bling.
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