My brushless gimbal result

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DennyR

Active Member
I think the dual motor concept could work and it could also work with a say 2:1 belt drive to also add torque. This would mean running two separate controllers and two IMU's.

By setting a very slight difference in the IMU attitude you would create a slight torque bias removing any backlash issues. I have successfully used this technique with servo drives.
 

Skysurf

Skysurf

Member
DennyR,

thanks for your reply. Do you think that using two of the 100g motors (like the ones you mentioned from iflight-rc) would be powerful enough to handle a camera of 1,5-2kg?

Would be nice not to have to use the gear reduction.

If using a third controller on the pan-axis, do you think that it could be done without reduction (using only one motor)?

Thanks again,

Jesper
 

nicwilke

nicwilke

Active Member
DennyR said:
I think the dual motor concept could work and it could also work with a say 2:1 belt drive to also add torque. This would mean running two separate controllers and two IMU's.

By setting a very slight difference in the IMU attitude you would create a slight torque bias removing any backlash issues. I have successfully used this technique with servo drives.
Click to expand...

Great idea.
 

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DennyR

Active Member
Skysurf said:
DennyR,

thanks for your reply. Do you think that using two of the 100g motors (like the ones you mentioned from iflight-rc) would be powerful enough to handle a camera of 1,5-2kg?

Would be nice not to have to use the gear reduction.

If using a third controller on the pan-axis, do you think that it could be done without reduction (using only one motor)?

Thanks again,

Jesper
Click to expand...

Think about it, If the gimbal is working correctly then the camera does not actually move or create inertial loads, accept when the operator gives an input. As inputs should always be slow and gentle then the motors only need a lot of power when the gimbal is a long way out of balance or has high frictional losses. In a perfect world with no outside disturbance (wind etc.) it would just sit there like a steadicam.
I think there's some potential for a large camera set-up.
 
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Skysurf

Skysurf

Member
Denny,

I fully understand and agree with what you are saying. My concern is - like you mention - the movements induced by the camera operator. If the camera operator is trying to follow a fast moving object and the camera has to tilt quickly and then stop - this might be a problem.

Regarding the pan axis, I guess it will be hard to do it without having some kind of gear reduction, especially considering the loads that will be placed on the motor/shaft if it is going to carry the weight of the gimbal and camera.

Thanks for your input.

Best,

Jesper
 

GotHeliRC

GotHeliRC

http://gothelirc.com
Well, I guess I will leave that to you guys to figure out. :) I will keep it simple by using 1 motor and 1 board.

About tilting the gimbal. Remember, this is why the camera need to be perfectly balance and no restriction by cables or such other. The only friction you're overriding and bearing friction. This is how the system works. So far from my testing with this motor it have no problem moving the camera, unless it's being held by something. IMO this is the only way to get a smooth control motion is by magnetic field / bearings. The only way to get a smooth motion with servo is to gear it down, but this is a different method. So how smooth it move depend on the code, motor power, bearings.

Alex recently add in some adjustment so the control motion can be adjust and tuned.


IMO, Simple Brushless Gimbal = Multicopter .
2 brushless motor per axis and 2 board = Multicopter with collective pitch. (no longer Simple).
 

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DennyR

Active Member
I agree with keeping it simple, The notion that you need to have a fast moving gimbal to allow heavy handed stick inputs is really something that will work against you and not help you. The less input the operator makes the better the footage will look. If you need to move the camera fast to catch sudden movements you are too close to what you are shooting. Chances are that the footage will not be usable anyway due to motion blur artifacts.
The other problem that you may encounter when moving the camera too fast is that you can saturate the gyro. This will cause the program to reboot in the middle of your shot. The last time I spoke with Alex he said that the 6050 is set at the highest sensitivity setting. To give an idea of how sensitive that is, consider this. For the IMU to sense a movement the camera baseplate must actually move. Well, did you see it move and did the camera see it move!!!
 
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Stacky

Member
The reason I thought I needed fast movements from a gimbal had nothing to do with heavy handed stick movements. I was concerned about windy days and the need for the gimbal to keep up with sudden changes brought about by gusts of wind which have more of an impact on smaller lighter multis.

DennyR said:
I agree with keeping it simple, The notion that you need to have a fast moving gimbal to allow heavy handed stick inputs is really something that will work against you and not help you. The less input the operator makes the better the footage will look. If you need to move the camera fast to catch sudden movements you are too close to what you are shooting. Chances are that the footage will not be usable anyway due to motion blur artifacts.
The other problem that you may encounter when moving the camera too fast is that you can saturate the gyro. This will cause the program to reboot in the middle of your shot. The last time I spoke with Alex he said that the 6050 is set at the highest sensitivity setting. To give an idea of how sensitive that is, consider this. For the IMU to sense a movement the camera baseplate must actually move. Well, did you see it move and did the camera see it move!!!
Click to expand...
 

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DennyR

Active Member
Stacky said:
The reason I thought I needed fast movements from a gimbal had nothing to do with heavy handed stick movements. I was concerned about windy days and the need for the gimbal to keep up with sudden changes brought about by gusts of wind which have more of an impact on smaller lighter multis.
Click to expand...

Stacky, think about it. The camera does not move, everything around it moves. The motors are just reeling in the slack so to speak. Only when you add stick input do they feel the weight of the camera.
 

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Stacky

Member
DennyR said:
Stacky, think about it. The camera does not move, everything around it moves. The motors are just reeling in the slack so to speak. Only when you add stick input do they feel the weight of the camera.
Click to expand...

Lets just say I am flying on a windy day and add no stick inputs, the multi will move around, some movements are smooth with the wind and others have bounces in them. Sure heavy handed stick movements result in a lot of unwanted movement but wind has an impact especially on lighter machines. I have a very light quad, I have put a simple Jakub gimbal underneath it and on a slightly breezy day I can see small jittery bounces in the footage, I then put the same gimbal under my big hexa and the footage is smooth. Then with the same gimbal under the Hexa on a windier day im seeing the identical bouncy jittery issues creep in to the footage.
The point is, not all gimbal corrections people are wanting are to compensate for heavy handed stick movements.
 

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DennyR

Active Member
Just to see what else may be required to get a brushless working properly, the wires from your camera may need to run through a hollow shaft motor OR one of these. This is the wiper track from a Zenmuse View attachment 10033View attachment 10034
 

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vip

Member

GotHeliRC

GotHeliRC

http://gothelirc.com
vip said:
First off congratulations on getting the motors together.
I would like to ask that you put up what the motors are used for on your site..
Like..... this one approved for go pro, this one for nex series.. etc..
Click to expand...

Done.

More size is coming in about 2 weeks.
 


GotHeliRC

GotHeliRC

http://gothelirc.com
Hi All,

I have listed the Gimbal up with pricing.

http://gothelirc.com/shopdisplayproducts.asp?id=201&cat=Brushless+Gimbal

I will try to give more details when I have more time. If you have been following the thread you probably know almost all.

I was hoping to put up a lower price but unfortunately with the low volume production it's very hard. I felt that I had give it my best and have been hard at testing it and to make it good, I think this is a fair price. :)

First batch is very limited, so first come first serve.

thanks
 

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tombrown1

Member
Looks great! Nice work on this project. One thing really holding me back is the first NEX video posted on the website which shows a huge horizon roll on the pan at the end. Has that improved, or is this just a limitation of Alex Mos?

Best,

Tom
 



jcmonty

jcmonty

Member
Awesome. Looks great!

Couple of questions:

1) Are you planning on releasing a larger size for Gh3/T2i sized cameras?
2) Will you sell the gimbal without the alexmos board? If so, what's the price for everything but the controller board?
 

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