My RC autogyro prototype - Page 5 - RC Groups
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May 20, 2017, 09:35 PM
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I enjoy rc autogyros just as much full scale flying since its such a new thing I haven't tried.

gyrobee gyroplane cruising to a friends strip (12 min 32 sec)


gyrobee gyroplane cruising to the cotton fields (7 min 39 sec)


gyrobee gopro side mount helmet cam test (3 min 44 sec)


cruising in gyrobee (11 min 27 sec)
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May 21, 2017, 09:20 PM
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I only got in a short flight today before the rain set in but I learned alot. basically with any trim or subtrim the stabilizer thinks your telling it to input a command and you have to toggle the flight mode switch really fast to let it know its neutral point. this is why it was turning left in auto level mode. Getting the level attitude right can be tricky depending on how fast you want to fly. Currently have a 50% rudder to aileron mix, will try a 100% rudder to aileron mix since it steers mostly with rudder anyway. All this will be covered in the 50+ page pdf file. I will be working on a website too that offers the free plans and other helpful stuff.
May 23, 2017, 04:51 PM
It's all in the Blades!
SafeLandings's Avatar
The problem with roll/rudder mix is that in certain situations with every flight you need to add opposite roll to flatten a turns etc (well I do any way). Wouldn't it be best to get a model flying almost hands free first? then compliment the model with a gyro after? I also find getting a few gyronuts to build your design is a bonus, they get to have fun and you get feed back and honest opinions.
The biggest issues with trying to replicate matching flight characteristics from one model to another is the head and blades, get these right and you can pretty much add what ever fuselage you want underneath.

I like the full size videos, is that you flying?

Keep at it

Rich
May 23, 2017, 08:10 PM
Registered User
Quote:
Originally Posted by SafeLandings
The problem with roll/rudder mix is that in certain situations with every flight you need to add opposite roll to flatten a turns etc (well I do any way). Wouldn't it be best to get a model flying almost hands free first? then compliment the model with a gyro after? I also find getting a few gyronuts to build your design is a bonus, they get to have fun and you get feed back and honest opinions.
The biggest issues with trying to replicate matching flight characteristics from one model to another is the head and blades, get these right and you can pretty much add what ever fuselage you want underneath.

I like the full size videos, is that you flying?

Keep at it

Rich
Thanks mate yes thats me. The roll/rudder mix just makes the turns more coordinated. I released the plans. They even show how to configure the lemon rx stabilizer plus for newbie pilots.
Last edited by RedBaron_RC; May 23, 2017 at 08:29 PM.
Aug 10, 2017, 10:44 AM
Registered User

Feedback


Quote:
Originally Posted by SafeLandings
The problem with roll/rudder mix is that in certain situations with every flight you need to add opposite roll to flatten a turns etc (well I do any way). Wouldn't it be best to get a model flying almost hands free first? then compliment the model with a gyro after? I also find getting a few gyronuts to build your design is a bonus, they get to have fun and you get feed back and honest opinions.
The biggest issues with trying to replicate matching flight characteristics from one model to another is the head and blades, get these right and you can pretty much add what ever fuselage you want underneath.

I like the full size videos, is that you flying?

Keep at it

Rich
Jeff,
Do you like Rich's idea of feedback from other gyronuts? You do call this a prototype, which pretty much means it is expected that some changes to the original will develop to improve the model. You've done a good job with this creation, but it is yours. Do you want us playing with your design and finding improvements to it?

Cheers,
Russ
Aug 10, 2017, 10:01 PM
Registered User
Your free to do what you want with the plans rus, modify to your hearts content.
Aug 12, 2017, 12:05 PM
Registered User

rotor tilt


Hi guys

I love this plan especially since its built largely with the dollartree foamboard. I notice the design only tilts left and right. Is the flight control sufficient using only the traditional rear elevator control ? Reason I ask is that I love the simplicity of only tilting in one plane, but it would seem to me that if you want to do the nose high super slow power OFF touchdowns, the elevator would be largely ineffective? If its still effective even at slow speeds without power, then I'm super eager to slap one together and try it !!

Jim
Aug 12, 2017, 01:57 PM
Registered User
Jim,
your conclusions are correct. Details, pros, and cons are explained in "17) What are the different rotor configurations like?" here: https://www.rcgroups.com/forums/show...ns-and-Answers

But it should be simple to modify the design to allow direct roll and pitch control.
Aug 14, 2017, 02:43 PM
Registered User

Flight tests and Modifications


Ok, here goes! Jeff...I'm not picking on your design, but rather using what I have learned about model gyros to improve Chippy. Chippy builds easily, quickly and cheaply, The rotor spun up quickly and she flew first launch. I see why you were fitting an electronic stabilizer, as she is not at all stable. Also, the following rate is too slow. By the time a rotor control input is given, Chippy has flown past where it was needed before the rotor responds.

Took the blade tip weights out and replaced them with bamboo skewer pieces. Back in the air....following rate now just fine as Chippy responds promptly. No change to stability, still a handful to fly. Moved the battery around to find the best CG, and climbed up to do a power off descent. Although the rotor was spinning fast, Chippy dropped straight down....way too fast for a safe landing, so aborted by applying power. Landings must be done with considerable forward airspeed (for a gyro). Chippy needs to fly faster than a gyro should, and is not very stable. Notice the motor gets very hot and there is a loss of power.

Replaced the vertical fin/rudder with a much larger one, and cut off the horiz stab angled pieces. Back in the air and stability is much better but rudder is too touchy......made the rudder smaller and solved that issue.
Last edited by rus1; Aug 14, 2017 at 04:30 PM.
Aug 14, 2017, 03:15 PM
Registered User

You are Flying the Rotor


It is important to remember you are flying the rotor. Everything you hang below has the purpose of power and steering. The rotor on Chippy is inefficient, not generating enough lift. This is demonstrated by the very fast sink rate with no power, and the fast landing speed required. The blades are quite thin and the airfoil shape only a little different than flat blades as far as their use on a gyro. Perhaps on a helicopter, driven and higher rotational speed they would be fine, but we can do better on our gyro without too much extra work.

The idea is to make a much more efficient airfoil from our dollar tree foam pieces, but keep the method similar. To accomplish this, we need to widen the width of the main blade blank to 2-5/8", and cut out a smaller piece the same length and 1-5/8" wide. After removing all the paper on all sides, we hot glue the smaller piece to the top of the larger piece by applying the glue and smearing with a popsicle stick before sticking the pieces together. The smaller piece is glued 3/16" back from the leading edge of the larger piece, which has the skewer glued to it.

Now we use our sanding block to make the leading edge of the top piece disappear into the bottom piece, and do the same on the back side, making the trailing edge 1/16" thick. Now we round off the top middle section to match and our airfoil is done. The process sounds difficult, but it is actually pretty easy in practice because the foam sands so easily.

Now we can make plywood blade mounts to accommodate the wider chord just like the original and use the big triangle as before. Or we can make "tangs" to do the same job and use a smaller triangle piece. We opted for the latter because we see the big triangle as having more drag, but both ways will work. We still use the rear skewer piece to set the angle of the blade, and in this case (with the wider chord) it is 2 degrees negative. Once again the blades are covered with packing tape as in the original, but more tape is used because of the wider chord and thicker airfoil.
Last edited by rus1; Aug 14, 2017 at 05:34 PM.
Aug 14, 2017, 03:52 PM
Registered User

We are Almost There


Back in the air with the new rotor....oops! The CG has drastically changed and we must move the battery as far forward as we can get it and stand it up, at that! Once this is done we find Chippy behaves as a gyro should. The following rate for rotor control is just fine. She flies much slower, is quite stable, hands off. Climb up to do a power off descent, and Chippy slowly floats down and easily makes a soft landing, The only downside is because we don't have a DC head, pitch control is minimal without the prop blast, and the really cool rotation just before touchdown that can be done with a DC head is not possible. Regular landings are much slower like gyro landings should be. Wow, what a difference! ...but remember...you are flying the rotor, and this is a much different rotor.

OK, so now Chippy is flying like a gyro should...stable, floaty, and slowly if desired. What else could be done to make it even better? The next change should be to look into the hot motor issue. Previously we learned that for their size, gyros need a different power system than a similarly sized fixed wing airplane. Gyros are like pulling a large trailer with a small car. You need power to pull because of the drag or weight and you need it in a lower gear. It takes a lot of work for that power system that would be perfect for the same size fixed wing airplane to pull that draggy gyro rotor through the air! That's precisely why the motor gets hot...its working very hard.

Chippy needs a motor that turns a larger prop at a slower speed. We need to increase the prop to a 10" prop with a lower pitch, and replace the motor with a motor that has a lower Kv, say in the 750-1000 range. This also means we must raise the nose to accommodate the larger prop by making the landing gear taller. This will also shorten the ROG take-off roll.

Oh, and here are some pics of how we balanced the blades for the new rotor. A short straight piece of popsicle stick is drilled to accept the rotor spindle and blades so we can balance the blades against each other until all are equal.
Aug 14, 2017, 08:56 PM
Registered User
Looks great rus! Now you see why the plans were free, so you guys were free to experiment. I need to buy a auto G to see what all the fuss is about.
Aug 14, 2017, 09:14 PM
Registered User
Quote:
Originally Posted by anitelite
Hi guys

I love this plan especially since its built largely with the dollartree foamboard. I notice the design only tilts left and right. Is the flight control sufficient using only the traditional rear elevator control ? Reason I ask is that I love the simplicity of only tilting in one plane, but it would seem to me that if you want to do the nose high super slow power OFF touchdowns, the elevator would be largely ineffective? If its still effective even at slow speeds without power, then I'm super eager to slap one together and try it !!

Jim
short answer no, and neither is the china made auto g2. If you want something that is super effective at slow speeds without power then I would suggest a glider. not trying to sound like a butthole
Aug 14, 2017, 09:34 PM
Registered User
have you been able to perform a loop rus? mine wouldn't do a loop no mater how hard I tried.
Aug 14, 2017, 09:49 PM
Registered User
you forgot the polyhedral tail rus, that was one of the key features in the plans, my original design had a polyhedral wing that crashed and burned.


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