DucktileMedia
Drone Enthusiast
not at all. It's my birthday today so i may not get around to it. PM me an email.
Photohigher skyline rsgs
- Thread starter 1001 Copters
- Start date
The MC and IMU should only be stuck with the supplied gummed paper. the dedicated soft mounting is inside the cases. Do make sure that the IMU has clearance around the top frame cut out.
Ok OK I give in. I'll be up all night at this rate. The answer was staring us all in the face. you cannot mount a high sensitivity gyro on a solid vibrating surface without getting feedback noise. Just disconnect it from the shaft and hold it in your hand and you will see the jitter stop there and then. What I did was to turn up a drive flange and then make a lead washer the same dia. this was sandwiched between the IMU and the flange with something called evo rubber (some small pads) this then formed a torsion dampener. I'll post some pictures later but I think you should get the idea. That is the source of the problem. That is not to say the firmware is perfect so lets see if they have done something with that as well. But with this you can go fly....
I would add to that. all of the loose wires that are not being used will have to be cut off as they will interfere with the imu as it can now move a little.
I would add to that. all of the loose wires that are not being used will have to be cut off as they will interfere with the imu as it can now move a little.
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Mactadpole
Member
DennyR,
PLEASE do post pictures. Your findings are much appreciated. Look forward to any videos you might be able to share of your results as well. I have just let mine sit in the box until it is all sorted.
Thanks, Shawn
PLEASE do post pictures. Your findings are much appreciated. Look forward to any videos you might be able to share of your results as well. I have just let mine sit in the box until it is all sorted.
Thanks, Shawn
Happy Birthday! A pm has been sent.
DJIFlyer
Member
Rotary Damper: I mentioned a few days ago that I was waiting for some parts to test an idea as it would apply to the jitters in pitch movement on the AV200 gimbal that I have my RSGS attached to. The parts came approximately an hour ago and I no longer have any jitter as this did exactly as I had hoped it would. The odd yellow attachment method that you see is just a couple of wire ties that I used temporarily to test my idea prior to making a proper mount or drilling a couple of tiny holes to hold the rotary damper down with. I will attach a couple of pictures below. This is of course located on the opposite side of the RSGS. I just got creative with a longer screw from the inside pointing OUT, filed a couple of flat sides on the end of that screw so that my set-screws has something flat to lock onto and that was it. The only other detail is the take the flanged bushing that they have and reverse it.
It Works!
View attachment 5547View attachment 5548
I will shoot some video in the days to come and will get it posted at that time. I hope that this will help some of you.
It Works!
View attachment 5547View attachment 5548
I will shoot some video in the days to come and will get it posted at that time. I hope that this will help some of you.
Attachments
DJIFlyer
Member
That's the problem, for the moment. I used one from an inexpensive Chinese gimbal that I had laying around to test this idea and it worked great. I am trying to find a supplier to provide me with several different ones in a range of resistance so that I can choose one and then share my findings. I am very happy with the results and the advantage (over creating friction with washers, etc.) is that once you find the right resistance it remains that way wereas just creating friction can change with wear and time. I will get to bottom of this this and share it with everyone as soon as I know more.
psionic001
Member
Here: Rotary Dampers
http://www.smallparts.com.au/store/categories/dampers+rotary+adjustable/all/
http://www.smallparts.com.au/store/categories/dampers+rotary+adjustable/all/
You have to provide a vibration dampening between the pitch shaft and the IMU. NOT the shaft and the frame otherwise the imu will not control the movement correctly. The shaft must remain free to move and be mass balanced or it will not work. killing the jitter by holding the shaft is not the way to do it. You have kill the jitter at the source of the problem which is incorrect gyro mounting.
If you strap down the pitch shaft, how can it possibly move in small increments. It will stay put until it overcomes the friction and then jump.
It is a known fact that a high sensitivity gyro setting is required to stabilize a camera, the trade off, is that it will be sensitive to all other movements including its own feedback if it is not mounted correctly. A pid algorithm cannot deal with bad mounting if it is to maintain it's designed sensitivity level.
Also once the imu has been mounted correctly it will have some small amount of free play in which to move against any vibration. This makes it sensitive to any loose wires etc. that are attached to it. These must be strapped down to the same base or removed as even a very small movement will produce an unwanted reaction at the camera.
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nicwilke
Active Member
Won't the damper simply assist sucking up the dead band? My cheap XA gimbal has oil dampers.
Sent from my GT-I9300 using Tapatalk 2
Take a look at just about every tail rotor gyro. they are usually supplied with an interim vibration absorbing plate that is sandwiched between the base and the gyro. the size and densities of the materials used are based on test results to determine the optimum characteristics. If you want to strap down your shaft in the belief that it will increase your servo deadband then go ahead my friend. If you want to destroy the resolution of the IMU then that is how to do it.
Why do you think that the Zen is almost friction free in all three axis. Why do you think that pro systems such as Cineflex run in air bearings. Friction and poor balance = loss of resolution and response time.
Those oil dampers that you mention are to reduce the airframe vibration getting to the camera mount. they would serve that purpose even if the mount had no stabilization movements at all. They are what is termed first stage vibration supression
Why do you think that the Zen is almost friction free in all three axis. Why do you think that pro systems such as Cineflex run in air bearings. Friction and poor balance = loss of resolution and response time.
Those oil dampers that you mention are to reduce the airframe vibration getting to the camera mount. they would serve that purpose even if the mount had no stabilization movements at all. They are what is termed first stage vibration supression
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1001 Copters
Member
Hi,
to obtain the best:
A/ mount the skyline on a servo plate with gyro gel mount between servo plate and skyline.
B/ use the H loom
C/ Control that you don't have any mechanical play in your gimbal AND servo. Otherwise, remove this mechanical play.
D/ use a small washer of plastics or nylon or other stuff that will create a little friction between tilt servo and gimbal
Hope you wil find this helpfull
best regards,
Cédric
Isn't it the same solution ? plcing the skyline on a small flange and glue it with Gyro gel like Khyosho ?
This mod has been described very early if I remenber well but effectively it's a good solution.
It's interesting to see that this solution (flange + gyro gel) has been found on french and US board nearly at the same time
nicwilke
Active Member
OK, I understand (I think), but the RSGS is reading the angle of the moving frame while on the moving frame. Its giving the signal back to the servo and the servo adjusts the tray accordingly.... Dampened or not, the RSGS is measuring the angle. Which comes first, the chicken or the egg? I thought the dampening would only make the servo work a little harder (small force). Could you please explain to me how my understanding is incorrect?
Isn't it the same solution ? plcing the skyline on a small flange and glue it with Gyro gel like Khyosho ?
This mod has been described very early if I remenber well but effectively it's a good solution.
It's interesting to see that this solution (flange + gyro gel) has been found on french and US board nearly at the same time
How many people does it take to change a light bulb? Answer= 100. Thats 1 to do it and 99 to say I could have done that.
View attachment 5549
I did not expect anything else. I should have left you crying in your beer.
Attachments
DucktileMedia
Drone Enthusiast
OK, c'mon. Denny, you get full respect for being one of the few guys on here who really understands this stuff. I am sure there will be skepticism, finger pointing and ultimately some gyro envy going on but lets not start throwing sand at each other. You have both made HUGE efforts on here to do what PH should have done but sometimes the guys designing the technical core of the product forget to plug it in and then wonder why it doesn't work. We have all been there. Have you ever asked someone where your hat was when it was sitting on your head the whole time? Ultimately, somehow, we are all in this together. We all paid money for a gyro that needed some help and although we wont get a paycheck for our hours of frustration, we may get a usable product. I really hope this is all it takes. I certainly was getting very close to returning the gyro after hearing I needed a new harness, 2 separate BEC's, fill my servos with grease, add a felt washer and 5 firmware updates. So i would laugh if all we needed was some ear plug foam(courtesy of Kloner) to fix the problem.
OK what you have failed to understand is that the IMU measures the angle relative to it's movement in space, it applies a correction signal that must not be corrupted by any other source if it is to point the drive system in the desired position. If you place external loads on the servo that interfere with the PID algorithm it will not return the correct resolution. i.e. it will keep jumping from one position to another. The pid algorithm controls how fast the servo starts and slows down as it approaches its final position it does not know how to handle a friction brake. This is all irrelevant until you understand the reason behind mass balancing. Newtons third law as I recall.
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Juri you are one of the real genuine guys here. Keep us all inline mate.
1001 Copters
Member
Hi Denny,
I have a big respect for your work, your knowledge and moreover your sharing of the info you have but I don't explain why some of your messages are a bit agressive :/
I'm a kind of alien in the world of multirotor webshop because I'm communicating a lot on boards and I publish tests of material. When I find a good product I'm trying to show the interest of it.
On the skyline problem, I have been as close to my customers as I can, I have seen that some of the resellers refuse to refund the customers. That's not my case and I have said it very early.
About placing the skyline on a small wheel, I have talked about this solution in the newsletter I have published This solution wasn't solving all the issues because there was two kind of problems: jitter comes from power source AND vibrations.
Using the H loom solve the power source surce problem but there's the vibration part. Another part comes from the mechanical play in the gimbal / servo.
Denny, if you want to speak about anything with me, perhaps I made something wrong or I'm upsetting you in some way, please contact me by mail or PM to see what it is, I can call you in the evening also to speak directly, it's always better to speak by phone rather than via boards
Best regards,
Cédric
I have a big respect for your work, your knowledge and moreover your sharing of the info you have but I don't explain why some of your messages are a bit agressive :/
I'm a kind of alien in the world of multirotor webshop because I'm communicating a lot on boards and I publish tests of material. When I find a good product I'm trying to show the interest of it.
On the skyline problem, I have been as close to my customers as I can, I have seen that some of the resellers refuse to refund the customers. That's not my case and I have said it very early.
About placing the skyline on a small wheel, I have talked about this solution in the newsletter I have published This solution wasn't solving all the issues because there was two kind of problems: jitter comes from power source AND vibrations.
Using the H loom solve the power source surce problem but there's the vibration part. Another part comes from the mechanical play in the gimbal / servo.
Denny, if you want to speak about anything with me, perhaps I made something wrong or I'm upsetting you in some way, please contact me by mail or PM to see what it is, I can call you in the evening also to speak directly, it's always better to speak by phone rather than via boards
Best regards,
Cédric