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Old Jul 12, 2012, 08:12 AM
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Originally Posted by 747Pilot View Post
I'm not convinced of this statement as of yet.....hmmm.
Not sure if this will help at all, but...

I think what is meant is that it takes some time for the accelerometer to stop registering the horizontal acceleration.

When a multicopter tilts forward it will accelerate forward. We know this because it will transition from stationary to moving forward. Eventually it will reach it's maximum speed for the given motor speed, this occurs when the drag is equal to the force propelling it forward. At this point it will continue on at a constant velocity and will not be accelerating.

An accelerometer measures Acceleration. When the multicopter is not accelerating the force of gravity is the only force that registers on the accelerometers (and it can tell which way is up). When it is accelerating forward there are components due to gravity and due to the acceleration of the craft registering in the accelerometers. Using accelerometers only there is no way to tell which components of that acceleration are due to gravity and which are due the craft accelerating, you have to wait for it to stop accelerating.

A 'draggy craft' is one that can change atitude (tilt) without accelerating.
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Old Jul 12, 2012, 08:46 AM
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Joined Aug 2007
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Originally Posted by Atx_Heli View Post
how does it work otherwise? does it work with a little throttle trim...perhaps the esc could be re-calibrated to start motor only at 10% throttle and the controller still work? does it freeze the servos when not in stablization modes?

I have three boards about to go into planes in my next project cycle and am very curious...let us know what you are finding!...thanks
the controller calibrates itself to min. throttle, while in "receiver test" I see throttle go from zero to full, you don't have PWM out while menu is active so no way to test when exactly AIL/ELEV freeze at 1.5ms, can't use fixed wing !
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Old Jul 12, 2012, 09:24 AM
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United States, PA, Warrington
Joined May 2012
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Quote:
Originally Posted by bjhoogs View Post
Not sure if this will help at all, but...

I think what is meant is that it takes some time for the accelerometer to stop registering the horizontal acceleration.

When a multicopter tilts forward it will accelerate forward. We know this because it will transition from stationary to moving forward. Eventually it will reach it's maximum speed for the given motor speed, this occurs when the drag is equal to the force propelling it forward. At this point it will continue on at a constant velocity and will not be accelerating.

An accelerometer measures Acceleration. When the multicopter is not accelerating the force of gravity is the only force that registers on the accelerometers (and it can tell which way is up). When it is accelerating forward there are components due to gravity and due to the acceleration of the craft registering in the accelerometers. Using accelerometers only there is no way to tell which components of that acceleration are due to gravity and which are due the craft accelerating, you have to wait for it to stop accelerating.

A 'draggy craft' is one that can change atitude (tilt) without accelerating.
Hi,

Yes, you're correct and I understand the physics of what you described.

However, I need to go back to the original quote:

Quote:
It needs some speed to get air resistance
&
Quote:
Therefore the autolevel works best on draggy crafts.
It implies that some type of air resistance, perhaps from steady state airspeed, turbulent air flow from "draggy" frames, a laminar flow, prop wash, or any type of air flow etc... would have a determination in the speed of correction by the auto-level feature. To imply that, isn't correct.

The KK2 board doesn't receive any input from a pitot tube or other source, The initial explanation could lead someone to believe air pressure or air flow has something to do with it. It simply does not.

-747Pilot
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Old Jul 12, 2012, 10:33 AM
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Originally Posted by Erknie View Post
I am going to try reflashing the Turningy Plush 6A with faster firmware, that should get the P setting back up. There is a thread somewhere in this forum I saw the other day about flashing the Scilabs version of the Plush 6A. http://www.rcgroups.com/forums/showthread.php?t=1686498
Thanks for the link; I may look into that (if only to get rid of the high pitched scream). I fiddled with P and I gains a little more yesterday evening and I found my turnigy micro quad seems to fly better when I bump the Pgain up to 60 and take the Igain down to 50 (from 100). It's possible I was mistaking the oscillations I was seeing for P-related when they were really I-related. I still get a bit of shimmy on aggressive maneuvers, but they don't compromise control in any way and it's more stable with the higher P-gain.
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Old Jul 12, 2012, 10:35 AM
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Originally Posted by bobepine View Post
And this is all I have to say about this.... For mow.

Best,
Chris

http://www.youtube.com/watch?v=jin1XZGsdPA
Hey KK Did You Watch This Video Looks Like There is some serious problem with manual so please check it out and get the manual right
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Old Jul 12, 2012, 10:40 AM
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Originally Posted by stwaller12 View Post
I hope this isn't a dumb question but I'm new to quad copters. I have a DJI 450 frame that I wanted to mount this board to. The frame only has mounting holes to mount the board like the old board with the corner pointing forward. This board seems to mount 90 degrees from the old, with the front of the board or flat forward. Can I mount it with the corner pointing forward or do I have to get a new frame? Any suggestions or comments would be appreciated.

Thanks,
Scott
Don't even think of mounting it the wrong way the sensor values will give a wrong output to the motor and will almost certainly result in a crash,just work something out to mount the board right or else buy a new mount
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Old Jul 12, 2012, 10:40 AM
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Originally Posted by Akcopter View Post
Hey KK Did You Watch This Video Looks Like There is some serious problem with manual so please check it out and get the manual right
The manual's motor pin order worked fine for many of us, myself included. It seems to me the problem is not the manual (not pointing fingers in any direction here ).
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Old Jul 12, 2012, 10:42 AM
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Originally Posted by rcbif View Post
How do I reverse a gyro? I need to reverse my tricopters YAW gyro.

It's either tha or I have to rewire the tiny servo, which I'm not sure my soldering skills are up to. Help!
hey check out the new updated manual and the procedure to reverse the yaw servo is specified
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Old Jul 12, 2012, 10:42 AM
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Originally Posted by 747Pilot View Post
It implies that some type of air resistance, perhaps from steady state airspeed, turbulent air flow from "draggy" frames, a laminar flow, prop wash, or any type of air flow etc... would have a determination in the speed of correction by the auto-level feature. To imply that, isn't correct.

The KK2 board doesn't receive any input from a pitot tube or other source, The initial explanation could lead someone to believe air pressure or air flow has something to do with it. It simply does not.

-747Pilot
It actually makes sense to me. I don't know if its true but what I think he's saying... If you start with your multirotor level and non-moving and it starts to tilt, very slowly, too slowly for the acc to notice then it'll start to pick up speed, again slowly, but then will reach a sideways airspeeds that equals the aerodynamic drag of the craft moving through the air and the acc realizes that its deaccelerating and will adjust. So a draggy craft will hit that resistance faster and harder, deaccelerate harder and get a quicker response.

I think I'll get a couple big sheets of foamcore board and set them up vertically to create drag in the forward/rearward and left/right movements for a test.
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Old Jul 12, 2012, 11:19 AM
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Originally Posted by pbmax View Post
The manual's motor pin order worked fine for many of us, myself included. It seems to me the problem is not the manual (not pointing fingers in any direction here ).
How can that be man!! really confused here.. my kk2 board is mounted on my tricopter for now but need to replace the old kk board on my quad and test it with this..will get back soon with my input
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Old Jul 12, 2012, 11:26 AM
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Originally Posted by Akcopter View Post
How can that be man!! really confused here.. my kk2 board is mounted on my tricopter for now but need to replace the old kk board on my quad and test it with this..will get back soon with my input
Worked fine on my quad too...
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Old Jul 12, 2012, 11:32 AM
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Guys please help. I cant seems to eliminate wobble, is it possible that my motor kv is too low for the frame or the prop is too big?

Quad Frame 450mm motor to motor, 750kv NTM prop drive, 10x45 prop 3s.

Thanks.
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Old Jul 12, 2012, 11:44 AM
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Originally Posted by rizky_p View Post
Guys please help. I cant seems to eliminate wobble, is it possible that my motor kv is too low for the frame or the prop is too big?

Quad Frame 450mm motor to motor, 750kv NTM prop drive, 10x45 prop 3s.

Thanks.
Nah, that's a good low kv motor and right size prop for it... Its what I'm using. I assume your not using flashed ESCs? Are they Plush or? Try lowering the p-gain on roll/pitch to 30. Then start bringing it back up until it wobbles, low it back a tad, and you're good!
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Old Jul 12, 2012, 11:53 AM
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Originally Posted by primeri View Post
Omg.. I almost lost my quad after i mounted kk2 to my Talon frame and testflew it. I hadn't any problems with kk1 thought.

In sensor test if I tilt board very hard to any direction, is it normal that kk2 tells that gyro's status isn't ok? Tried to flew my quad and it was almost uncontrollable. It tries to correct itself really aggresively. I think some of that is beacuse of gains, but how's that sensor test result. I have calibrated sensors and done all that basic stuff.
hey that's what happened to me while testing the sensors moving the board a bit wildly changes the status of the gyro on the board from ok to not ok..is this normal..I flew with this board not a problem,but did not go wild with it ....kk plz help..
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Old Jul 12, 2012, 12:00 PM
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Originally Posted by Akcopter View Post
hey that's what happened to me while testing the sensors moving the board a bit wildly changes the status of the gyro on the board from ok to not ok..is this normal..I flew with this board not a problem,but did not go wild with it ....kk plz help..
See this response...
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