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Old Oct 15, 2012, 10:52 PM
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Originally Posted by tiede3d View Post
Yes, this stabilized platform is carried by hand and not flown.

I haven't computed the value of the inertial mass that might be needed. But the servo doesn't need to move the center of mass of the whole upper mass, only a small balancing mass relatively far from the center gimbal support. It is the torque which is mass times lever arm which is important. In this case the lever arm is large (maybe 6 or more inches) and the balancing torque needed should be small because the whole assembly is almost perfectly balanced to begin with. I imagine something with the mass of penny moved an inch or two might be the order of magnitude needed. The movement of the mass can be nearly frictionless so the servo motor wouldn't need to do much work . Both the mass (and thus the force) and the translation distance are small. As to servo torque, if the RPM of the servo motor is high enough, the translations can be smoothly accomplished even with low torque using the mechanical advantage of a screw with a large number of threads per inch.

I don't really need to worry much about how much mass is needed for batteries, controller, or servos because whatever is needed can be distributed or compensated with other additional mass to keep the platform center of mass over the gimbal. Since it is hand carried, a person can easily support the mass even with two small HD video cameras and all the hardware. The design allows a support rod attached to the gimbal to be further supported by a pocket attached to a belt.
You might have more luck contacting Eagletree directly or billpa who started this thread. I find this thread is really all about the primary function of the Guardian which is airplane stabilization, not camera platforms.
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Old Oct 16, 2012, 01:31 AM
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Originally Posted by tiede3d View Post
Hi,

I'm interested in 'flying' a hand held video camera stabilization rig of my own design but which works something like the Steadicam Merlin. These rigs work by balancing the camera support platform on a gimbal. The whole thing is essentially a pendulum with a slightly larger mass below the gimbal to keep it 'balanced'. It is difficult to keep the support from swaying when accelerated and to aim or pan the camera where desired.

My goal is to attach a 3D control system such as the Guardian to such a stabilized platform. The outputs would simply move masses on the horizontal x and y axes to keep the platform level as it is accelerated in various directions. I'd also like something like the hold heading feature used on airplanes to keep the stabilizer pointed in a fixed direction.

Since the members here are all experts at RC motion control, my question is could the Guardian system be used for my application even though it isn't a motorized vehicle or airplane?
Guardian is an excellent but highly developed and dedicated air plane stabilizer. I think you should check also some more "primitive" but very programmable devices like Ice-Man BL-3G or even Arduino based gyro-boards.
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Old Oct 16, 2012, 03:58 AM
Rick
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Joined Mar 2011
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Quote:
Originally Posted by tiede3d View Post
Yes, this stabilized platform is carried by hand and not flown.
I think the Guardian is quite capable of handling a gimbal system. A couple of us have experimented some with (I think) fairly primitive airborne camera stabilization. I know my setup is really primitive. What you are describing sounds beyond anything I have heard discussed here.

Originally Eagle Tree said they intended to expand the firmware for gimbal applications but haven't announced anything further. The best suggestion seems to be to get in touch with Bilpa, perhaps by pm, or perhaps open a support ticket.

I doubt that anyone here has the solution you are seeking but some love a challenge. If you want to pursue help here, perhaps a few photos or a diagram would facilitate better suggestions. It sounds doable but breaking new ground may require experimentation and some blind alleys.
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Old Oct 16, 2012, 04:23 AM
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Ok starting to lose patience now, paid for my ET G back in late Aug, and it shipped 24 Sept. The tracking number provided hasn't changed status for about 3 weeks. Contacted ET and they were not very helpful saying it can take 3-16 weeks.....not in my experience from the US-Aus, two weeks is very typical. Contacted USPS and no reply. Ended up ordering another from from Fast Lad UK and it shipped the next day. Knowing my luck the second one will arrive before the first. Frustrating waiting...

Now having had a rant, a question regarding setting max travels, I assume one should turn the ET off, verify max travels on full rates, then set the 2D or 3D mode and then tilt the plane 45dgs away from the heading to check the travels are no more than the max travels normally set up without the ET on. This process doesn't seem well documented in the manual and I wondered what others were doing in this regard. Might as well learn up on setup whilst I wait for this box o' tricks to arrive....Cheers.
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Old Oct 16, 2012, 04:32 AM
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All servo linkages should be such that at full travel nothing binds ,that ios get mechanical setup correct first. IMO having a setup that will stall a servo and then reducing EPA or using D/R to prevent this is just plain wrontg.


Compared to a clock face 12 on the G 2D/3D Pots is no gain / correction. You will need to turn pot s CW or CCW to obtain correct direction of correction. Start with 10 or 2 O clock and increase in small steps.

Charles
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Old Oct 16, 2012, 04:53 AM
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I agree Charles but from what I've read on this forum the ET can command greater throws than your programmed Tx limits can't it?

Also can I keep my Differential and Rudder mixing with Ailerons through the ET module? I quite like the way I've set up my bird so far, and whilst I see there is a 'complete the turn' feature I would prefer to control this in my Tx. Cheers
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Old Oct 16, 2012, 08:43 AM
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Originally Posted by Flyindude View Post
I agree Charles but from what I've read on this forum the ET can command greater throws than your programmed Tx limits can't it?

Also can I keep my Differential and Rudder mixing with Ailerons through the ET module? I quite like the way I've set up my bird so far, and whilst I see there is a 'complete the turn' feature I would prefer to control this in my Tx. Cheers
Yes it definitely does not constrain itself in any way to what your radio commands. In the PC set up, you will see the servo set up page, the default min/max limits are very large, it only obeys those limits. You need to set them up for your specific plane.

All your custom mixes flow right through to the plane. The Guardian will modifiy any and all of your radios inputs to perform its function so at any one instant your mix may not be accurate but the Guardian does not block anything. I have rudder to aileron mixes that still work fine. I also have a flaperon setting that works as well.

I find the 'complete the turn' feature quite bizarre. I think it is because I fly co-ordinated turns normally anyway where I guess a lot of RC people don't use rudder.
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Old Oct 16, 2012, 02:23 PM
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Flyindude, sorry about your situation with international airmail. It's usually pretty reliable, but the outliers can be really frustrating. My guess is that customs is the likely culprit.

tiede3d, we're indeed working on gimbal and other features, but I don't have a timetable for release of those features at this point. Will be posting here, of course, when we get there.
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Old Oct 16, 2012, 02:28 PM
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Living in Canada I know that tracking only works till it leaves the states.
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Old Oct 16, 2012, 02:49 PM
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What some seem to be missing is that if controls do not bind with servos at the max limits the Guardian will not cause them to bind atleast to the best of my knowledge and experience..

IMO way to many set servo arm lengths and control horn lengths to the point that 100% of normal servo travel will cuase stalling / binding and then they use reduced EPA to prevent this binding. I am saying that if the mechanial setup is correct there will be no binding.

If someone has found that Guardian will drive a servo past its' 45 or 60 degree normal travel range then this could be a seriuos issue.

As I have mentioned these days I am flying helis and learning about FBL units. Not saying these are the same as the Guardian however they are programed for total travel of servos in their software and if one uses reduced Trans, travel by way of the D/R the FBL will still drive the servos to the max. range set in the software.

This means that if the swashplate can bind at the max. throw limits set in the software then reducing the travel by way of the Transmitter does not help.


Charles
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Old Oct 16, 2012, 03:15 PM
Launch the drones ...
Ashtabula, OH USA
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Quote:
Originally Posted by everydayflyer View Post
What some seem to be missing is that if controls do not bind with servos at the max limits the Guardian will not cause them to bind atleast to the best of my knowledge and experience..

IMO way to many set servo arm lengths and control horn lengths to the point that 100% of normal servo travel will cuase stalling / binding and then they use reduced EPA to prevent this binding. I am saying that if the mechanial setup is correct there will be no binding.

If someone has found that Guardian will drive a servo past its' 45 or 60 degree normal travel range then this could be a seriuos issue.

As I have mentioned these days I am flying helis and learning about FBL units. Not saying these are the same as the Guardian however they are programed for total travel of servos in their software and if one uses reduced Trans, travel by way of the D/R the FBL will still drive the servos to the max. range set in the software.

This means that if the swashplate can bind at the max. throw limits set in the software then reducing the travel by way of the Transmitter does not help.


Charles
From your post, I'm unsure whether or not you're aware that servos can be limited to 100% travel using the PC SW that ET provides for programming the Guardian.
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Old Oct 16, 2012, 06:43 PM
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Originally Posted by Tim Green View Post
From your post, I'm unsure whether or not you're aware that servos can be limited to 100% travel using the PC SW that ET provides for programming the Guardian.
Yes I am aware of that but are you or the ones with issues seeing the Guardian 2D/3D with default settings drive a servo witht a signal outside of the normal 1.100 to 1.900 range?


What is defined as 100% travel a range other than I posted?
What range will the default Guardian achive?

Charles
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Old Oct 17, 2012, 08:20 AM
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United States, AR, Benton
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Short extensions for USB connection

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Originally Posted by simages View Post
Try this site USBFIREWIRE That's a micro-b plug I believe and you should be able to get just what you need for easier access.

http://www.usbfirewire.com/
Thanks! I ordered four of the 5" micro B extensions to give a flexible connection with USB to laptop, also two of the 12". This should make program adjustments and resets at the field much easier. ET should offer the 5" on their site as it can be difficult to attach the stiff cord they sell to a unit mounted at CG in fuse or cabin.
Jim
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Old Oct 17, 2012, 08:30 AM
Launch the drones ...
Ashtabula, OH USA
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Quote:
Originally Posted by everydayflyer View Post
Yes I am aware of that but are you or the ones with issues seeing the Guardian 2D/3D with default settings drive a servo witht a signal outside of the normal 1.100 to 1.900 range?


What is defined as 100% travel a range other than I posted?
What range will the default Guardian achive?

Charles
Nope - I have no servo grinding issues - but I did set my max servo travel to 100% using the ET software - which is why I don't have any servo grinding issues..
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Old Oct 17, 2012, 08:39 AM
Launch the drones ...
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Used my Guardian 2D/3D for the first time yesterday - and I had fun with it. Lots of fun.

Launched hands off in 3D (full throttle), and whatched as the plane kept on going up that launch path, getting smaller, and smaller - until I took back control of the aileron stick.

Did big lazy circles up in the sky, using 2D, by merely holding the aileron stick to one side or the other.

Landed once in 2D - but there was no wind to speak of yesterday, so cannot say much about landing in 2D. (Except watch out for those big wide 2D turns, if you have a tight landing space)

It is possible, to relax while the plane almost flies itself in 2D circles, with this device. I was flying in a Finwing Penguin - its maiden flight actually. Nice FPV plane. Had my pots at 50%, and my transmitter gain at 100% - no oscillations. Will try my pots at 75% next time.
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