Is any work being done by the development team to add this class of vehicle to the capabilities of the APM or Pixhawk series of autopilots? The Arcturus design is very nice and looks like a very useful cross between Multi-rotor and normal aircraft designs.
here is a link to their site - http://arcturus-uav.com/index.html
dennis
Comments
Rob...
one more thing. design the three multi-rotor (tricopter) props to incorporate the foldback capability of glider props so when the horizontal flight puller props are in use the three tricopter props streamline to reduce drag.
dennis
Rob....
I think I understand what you are saying. I have been looking at the FireFLY6 -
http://www.birdseyeview.aero/products/firefly6
and your post makes me wonder if the props/engines on that vehicle should be re-engineered. perhaps two of the props on the front two pods should be optimized for normal "airplane" flight and only used for that when the pod is in level flight configuration. perhaps eliminate one of the props at the back since there is no need for a prop back there for horizontal flight. finally, optimize the two remaining props in the front and the remaining back prop for multi-rotor (tricopter in this case) flight. the end result is two puller props in the front optimized for forward flight horizontal flight and three props (tricopter) optimized for VTOL operations. your thoughts?
When I read things like this... What if I told you that you can get an off-the-shelf solution for about $2-3000. It's very mature technology. You have several choices of manufacturers. They can fly for 2 hours easily, at up to 100 km/h. It has excellent VTOL capability, and can hover in almost any wind condition. It can lift up to 20lbs if you want to, but typically would limit to 5-10lbs if you want to achieve the flight duration I mentioned previously. They weigh only about 15lbs, and are only 1.5m long, and 15cm wide. This is available *today*.
All of these proposed new aircraft need to beat those performance metrics to really make sense.
There's actually a lot of misconceptions around the idea of high-pitch props on multirotors. Basically in the early days of multirotors, with low motor efficiencies, lack of availability of purpose-made motors, poor frame designs, poor controller design, etc, Slow Flier props were needed. But those same factors don't exist anymore, and people aren't circling back to look at the science again, or just doing a bad job of that.
There's a guy on RCG... Ferdinand? He's been pushing this stuff, but nobody seems to be listening. He's setting endurance records, with 6" pitch props. And he's got quads that can actually fly 45 minutes, with a payload, and I mean *actually fly* at up to 10-15 m/s or so. He's doing something right.
There's considerable room for improvement here.
I don't have all the answers on this. I'm just saying... the conventional wisdom most people operate with right now isn't it.
For example, most people think that low pitches are required to prevent stalling the blade, because we are effectively operating statically. But you have to remember, that the propeller creates it's own inflow. It doesn't operate statically. That inflow velocity can be quite high, allowing really high pitch props. But an issue arises when you accelerate the propeller too fast, before the induced flow can accelerate, then you can get stall.
Consider for example, the tail rotor on a heli. Most have up to 45° of pitch available. What's the linear pitch of that? Extremely high. But we use them in a static condition. You only run into trouble if you move the pitch too fast, before velocity builds, then you can get stalling. But even then... when you stall the tail rotor, you don't really get in a condition where thrust stops, you just get in a situation where thrust does not rise linearly with power. The tail rotor sucks all this power, but doesn't make tons of thrust. It's still making substantial thrust though.
Sorry, rambling post... Point is just that I think these things can be made to work just fine with fixed pitch props. You just need to engineer the system right.
- Mathieu: I could not translate the Russian on the ArduVTOL page, but it seems like this guy has something
nice and semi-familiar in the works.
- Dennis: I am not too sure as to the Bolt-On concept, but what the heck.
I actually have a file on my PC where I did an initial design mashup of Flying Wing-
come-XOcto. It had the basic genetics of the RVJET, Skywalker X8 & Boeing 747.
Then the FireFLY6 came out - and the airfoil looks the spitting image of what I was
sketching out. The FireFLY6 is actual a Wing + Y hexacopter, and for the life of me,
I cant figure out the dual AutoPilot reasoning, but it seems to work.
There is also the WingCopter project from Germany, which works solely using a single
APM and close to no code changes - http://www.wingcopter.com/index.html.
Actually, here is my little VTOL collection, not all too serious :-)
https://www.youtube.com/watch?v=ShEg93DgbsE
https://www.youtube.com/watch?v=BWQiaYLgIaI&list=PLpjBzEYlFBlAI9...
https://www.youtube.com/watch?v=MlbZQ01hwO0
https://www.youtube.com/watch?v=fOJ8TWYUedA#t=107
One more thing....
I really like the idea of a "kit" that can be added onto existing airframes. The "Jump" solution i found that started this thread is just that - a bolt on kit. A whole new technology area would be created that involved design, manufacture, and sale of kits that could turn the MILLIONS of existing rc aircraft into multi-rotor vehicles if the software to control this configuration existed in one simple place. Where better than the ArduPilot community? My guess is the 95% of the software development effort is already done - we just need to accomplish that last 5% and create this "new" class of vehicle to augment plane, copter, rover, ......
GO TEAM!
dennis
Gil....
I totally agree with you on every point you make. I started this thread because I am looking for a solution to a Search and Rescue (SAR) need that doesn't allow for a fixed wing landing strip in all cases. SAR needs the extra endurance (legs) of a fixed wing platform over a multi-rotor vehicle. A blend of multi-rotor and fixed wing capabilities with fixed wing like cruise performance that simply DOUBLES the flight time of a multi-rotor in cruise mode while still allowing for very limited hover (close look mode) and VTOL is my goal. The SAR goal is to find/save people so efficiency is much less important to me than functionality; i don't really care if there is a trail of disturbed air behind the vehicle generated by the non rotating lift rotors while cruising as long as i can generate that tubulance for twice as long with this vehicle as i can with a multi-rotor craft. Moving parts just make things more complicated and likely to fail so rotating wings/rotors/surfaces just seem to make the solution more complex (aka - heavy) IMHO. Whoever develops this capability will end up with their picture on the wall in all Search and Rescue facilities..... I am an aerospace engineer and not a programmer so I know what I want (need) but not how to accomplish it with the software; if this were to turn into an APM/Pixhawk project I would certainly sign up to participate in any way i could. I am a HUGE fan of the APM/Pixhawk system and development team and would like to see the solution to this real need come from here as opposed to a commercial entity (DJI?).
dennis
The Arduvtol is a solution, but it is not open...
or there is https://sites.google.com/site/hobbyarduino/project-updates/theresul...
Hi Guys -
I want to second and support the initial request.
The suggested "Quad+Wing" configuration, and its "Tri+Wing" little brother
are much needed for certain applications, despite what you may have in mind.
These craft are very usefull for controlled land survey and search-and-rescue
applications, and require the carrying capacity for meaningful payloads,
not just GoPros.
I, for one, would very much love to see an APM/PixHawk solution for these layouts,
with a proper solution for transitioning between flight modes and perhaps setting up
a 9th control channel for the Forward (Wing) prop. A certain Mil-Spec manufacturer
has configured such a craft with Electrics for the VTOL part and Gas for the forward thrust,
claiming for better efficiency. There is of course the cool-cat FirFLY6 ( http://vimeo.com/birdseyeviewaerobotics )
but that is still a little awkward and doesn't have the mission and payload capacity we require.
Having the VTOL on a fixed wing solves the "landing" issue when you are carrying $$$ optic sensors,
currently addressed with parachute pods. Etc. Etc.
The person to code this for the APM / PixHawk will go down in my personal book of saints & geniuses!!!
From what I've heard, the V-22 is pretty good. It did have some problems in the beginning but nowadays it works and their crews (and the field commanders) love it.
-
1
-
2
-
3
-
4
-
5
of 5 Next