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  • Hey all, just changed over the backend after 15 years I figured time to give it a bit of an update, its probably gonna be a bit weird for most of you and i am sure there is a few bugs to work out but it should kinda work the same as before... hopefully :)

Letus Gimbal

PC Greene said:
My understanding is that for ultimate control, responsiveness and accuracy, optical encoders & a closed loop system is superior otherwise motors are just freewheeling. Similarly gps is becoming A standard for high speed work.

Thank you,
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Which systems use optical encoders?
 
I don't know about optical encoders but, if I am not mistaken, GPS is typically accurate to about 3 meters so I can't see that being helpful in too many situations other than perhaps operating from a helicopter. What am I missing?
 
PC Greene said:
MoVI, & B4 to start...
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Can you point me to the info where that is stated...
Because it is nowhere to be found that that is the case.

To my knowledge you needed Optical encoders on Servos with the older freely gimbals. And with the current state of tech. with brushless motors you don't need that.

Freefly has the GPS for 'drifting' horizon' compensation... this could be useful. They say if you drive with a car or moving fast this would be useful.

With the current basecam board (The standard one) you have the option for a second IMU for even greater accuracy. I guess If you have to points of measurement you could compensate for 'Horizon drift'.
I only know that Hienle is working directly with the base cam team (From earlier info) So how the implementation is done on the Helix he has to fill in.
 
I scoured the BeSteady4 web site looking for this and found nothing. I was hoping for an explanation of optical encoder functionality.

FWIW, I seem to recall that Helix does utilize the second IMU in its design.

EDIT: Per the Helix web site -
  • Second IMU that increases the short-term precision of the stabilization 10x-30x times.
 
I read somewhere a few months ago that the BeSteady4 is using a custom 32bit Alexmos controller with optical encoder feedback and a different GUI and that they work directly together with Alexmos for that, probably this info is hidden somewhere in the BS4 group buy topic. That's why I actually expected that the new 32 bit controller will also use optical encoders. For some reason Alexmos decided to use a second (frame) imu instead and I'd guess that this approach works at least equally good.

Eventually it's just essential for long term stability to have another feedback device at all, which is not placed on the camera plate but connected to the frame to give feedback on the orientation of the gimbal. Optical encoders will be not precise enough to play a role in the actual stabilization control loop anyway. If it's a encoder with 1024 steps the angular resolution is only 0,35 degrees, if it's 4096 steps the angular resolution increases to 0,088 degrees which is still not as fine as the MPU6050 itself can do. They only produce additional data for verification, which is important regardless.

Best regards,
Andreas

www.portahead.de
 
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The final BeSteady Four design will implement 2 IMU (Inertial Measurement Units) – one located on the camera shelf and a second on the mainboard, inside of rear arm. It will also implement optical encoders inside each motor. This hybrid solution is completely unique to the BeSteady Four. This offers super accuracy of around 0.09 degrees from the sensors and no drift. Actual physical stabilisation will be accurate up to 0.2 degrees.
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From BeSteady site.
 
Hello Jean,

that's probably the actual post were I read that BeSteady is/was working together with Alexei Moskalenko: http://www.reduser.net/forum/showth...imbal-Thread&p=1245446&viewfull=1#post1245446
Maybe there was another one which mentioned the custom Alexmos 32 bit controller.

However, that time a custom Alexmos 32 bit controller was a kind of unique feature like the usage of optical encoders. Now that the 32 bit controller from Alexei Moskalenko is commonly available they somehow prefer not to mention their relation to him but of course still use the words unique, optical encoders and 2 IMUs for marketing reasons. But as I said before, a second IMU or optical encoders (...or both) are clearly usefull to give feedback on the orientation of the gimbal and for long term stability.
 
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Interesting, they claim something Alex himself said not possible in a personal email to me recently, that is "it offer 360 degree stabilisation on every axis". While Alex said "only 2 of 3 axis will rotate full 360 degree". And that's the limitation of all the gimbals out there. Also, you can put an encoder into the motors, but it needs a controller that can use that data, which the current 32-bit doesn't. They went with the route to use the second IMU, which we do implement. As far as I know, Dimitri was right, Movi went off the path of optical encoder since they went Brushless last year.
 
Thanks for jumping in here, Hien. Being as this is a new area for a lot of us, it helps to have informative commentary such as this to keep out any hype that might creep in.
 
[M10 and B4 most certainly have optical encoders and M10 also has GPS.

Interested in testing our M10 in comparison to B4 and Helix towards reducing hype and nailing down what practical advantageous each sensor provides...

Thank you,

hienle said:
Interesting, they claim something Alex himself said not possible in a personal email to me recently, that is "it offer 360 degree stabilization on every axis". While Alex said "only 2 of 3 axis will rotate full 360 degree". And that's the limitation of all the gimbals out there. Also, you can put an encoder into the motors, but it needs a controller that can use that data, which the current 32-bit doesn't. They went with the route to use the second IMU, which we do implement. As far as I know, Dimitri was right, Movi went off the path of optical encoder since they went Brushless last year.
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PC Greene said:
[M10 and B4 most certainly have optical encoders and M10 also has GPS.

Interested in testing our M10 in comparison to B4 and Helix towards reducing hype and nailing down what practical advantageous each sensor provides...

Thank you,
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PC - can you enlighten us on the specific functions and benefits of these optical encoders? (Or point us to a source to gather this info for ourselves). And what about the controller issue; how is that integrated if, as Hien says, the current 32-bit system doesn't handle it. We seem to have some conflicting (or at least, confusing) information here and it would be nice to get it reconciled. Thanks!
 
I have a feeling that we are entering a phase where people are comparing specs while missing the greater point.

One man's opinion; at the end of the day, it will come down to the skill, training and creative eye of the operator.
It's just like owning a RED camera does not make you a world class cinematographer. It's how you use it.

Will an inexperienced operator actually see a difference between encoders? Will an experienced operator?
Will it turn into a matter of personal taste? If so, what do specs matter when comparing the best effort each manufacturer brings to the table?
Ergonomics alone may be more of a factor in producing the end result than anything else. Then again, maybe not.
It may be the type of shot - one gimbal may handle a particular move better than another.

Perhaps we will learn over the next few months what real world advantages one system or design approach may bring over their competitors.
When we do, it's knowledge to bank.

These are wonderful times for image creators - more tools are becoming available that provide new and exciting options when visualizing a scene.
It looks like gimbals will be everywhere this year - cannot wait until I see the results!
 
Brian F Kobylarz said:
I have a feeling that we are entering a phase where people are comparing specs while missing the greater point.

One man's opinion; at the end of the day, it will come down to the skill, training and creative eye of the operator.
It's just like owning a RED camera does not make you a world class cinematographer. It's how you use it.

Will an inexperienced operator actually see a difference between encoders? Will an experienced operator?
Will it turn into a matter of personal taste? If so, what do specs matter when comparing the best effort each manufacturer brings to the table?
Ergonomics alone may be more of a factor in producing the end result than anything else. Then again, maybe not.
It may be the type of shot - one gimbal may handle a particular move better than another.

Perhaps we will learn over the next few months what real world advantages one system or design approach may bring over their competitors.
When we do, it's knowledge to bank.

These are wonderful times for image creators - more tools are becoming available that provide new and exciting options when visualizing a scene.
It looks like gimbals will be everywhere this year - cannot wait until I see the results!
Click to expand...


Skill is always a given. Without it, one gets less than ideal results. But, I think, in this case, it may be an issue of whether a particular set of technologies will actually live up to the promise. When we are talking about encoders, I don't think "we" (although I can only speak for myself) are talking about whether micro measurements are going to make a difference in a specific shot but, rather, whether the technological details will fail to deliver what is promised. In other words, will the "wrong" encoders actually mess something up, kind of like a lens that can't get focus or a tripod head that sticks erratically. For me, it would be nice to know what the technology is, what it does and how it might help, and what might go wrong in its operation.

One thing I don't want is for claims to me made which confuse the actual facts. Are optical encoders actually used? If so, why are they "better" - or are they? If so, what do they actually do? Will it actually matter in the performance? If so, how and under what conditions? If one suggests they are not helpful, where is the actual disagreement? In the end, actual facts are better than misinformation or hype so that we can agree on them and move on to more substantive issues of performance.

And, yes, gimbals will be the latest craze - I am thinking the real innovators in 2015 will be going for the "shoulder mount look." :smiley:
 
Terry VerHaar said:
Skill is always a given. Without it, one gets less than ideal results. But, I think, in this case, it may be an issue of whether a particular set of technologies will actually live up to the promise. When we are talking about encoders, I don't think "we" (although I can only speak for myself) are talking about whether micro measurements are going to make a difference in a specific shot but, rather, whether the technological details will fail to deliver what is promised. In other words, will the "wrong" encoders actually mess something up, kind of like a lens that can't get focus or a tripod head that sticks erratically. For me, it would be nice to know what the technology is, what it does and how it might help, and what might go wrong in its operation.

One thing I don't want is for claims to me made which confuse the actual facts. Are optical encoders actually used? If so, why are they "better" - or are they? If so, what do they actually do? Will it actually matter in the performance? If so, how and under what conditions? If one suggests they are not helpful, where is the actual disagreement? In the end, actual facts are better than misinformation or hype so that we can agree on them and move on to more substantive issues of performance.

And, yes, gimbals will be the latest craze - I am thinking the real innovators in 2015 will be going for the "shoulder mount look." :smiley:
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The proof will be in the products delivered.

With so many of the products converging to come to market within a relatively short time span of each other, it is perhaps a bit unfair to bait and challenge manufacturers to reveal too many details in advance of product release.

In much the same way as Jim Jannard learned with RED, his competitors absolutely loved it when he revealed too much too soon.

They are all so close, perhaps it is time to give everyone the opportunity to prepare their products for release without sideline speculation.
I think we can all pass the time with some anticipation, even healthy suspense as we approach the finish line.

To me, the best part is that with all the competition, everyone is working to build the best they can - and we are the beneficiaries - better products at lower costs.
 
Brian F Kobylarz said:
The proof will be in the products delivered.

With so many of the products converging to come to market within a relatively short time span of each other, it is perhaps a bit unfair to bait and challenge manufacturers to reveal too many details in advance of product release.

In much the same way as Jim Jannard learned with RED, his competitors absolutely loved it when he revealed too much too soon.

They are all so close, perhaps it is time to give everyone the opportunity to prepare their products for release without sideline speculation.
I think we can all pass the time with some anticipation, even healthy suspense as we approach the finish line.

To me, the best part is that with all the competition, everyone is working to build the best they can - and we are the beneficiaries - better products at lower costs.
Click to expand...

The main difference in all this is that Hien at Letus has been extremely forthcoming here on this thread. I consider that a HUGE bonus to the end users as we make our choices. It would seem that he is not afraid to reveal his technology and his thinking and, in fact, step up and change things when someone has a good suggestion. Letus is preparing their product in a timely fashion and still takes time to comment here.

If someone is going to make a claim about optical encoders but not tell us why we should care, then it is marketing hype. There is nothing mysterious about their inclusion as they are revealed on the web site (or is it possible that could be old "leftover" information and doesn't apply. But assuming it is accurate, why would it be so hard to explain why we should value their inclusion. That is not giving their competition any special insight as the engineers employed by their competitors most likely know about optical encoders, etc. What I am looking for is a clear explanation as to whether this is a significant market differentiator or a trivial detail, like making it gray instead of black.
 
Optical encoders built into the brushless motors provides feedback to the control system so it is constantly "aware" of the precise physical position of the motor(s).
Without this, the system is constantly "guessing" as to where the motor actually is.

How much this (or the benefits of GPS on fast moving gimbals) translate into real world benefits won't be known until differing systems performance can be compared.

Thank you,

Terry VerHaar said:
PC - can you enlighten us on the specific functions and benefits of these optical encoders? (Or point us to a source to gather this info for ourselves). And what about the controller issue; how is that integrated if, as Hien says, the current 32-bit system doesn't handle it. We seem to have some conflicting (or at least, confusing) information here and it would be nice to get it reconciled. Thanks!
Click to expand...
 
I dunno Brian...a whole lot of money is being thrown around - as are performance claims in this space.

While it is certainly the right of the manufacturers not to share more than they wish, it's also the right of the consumers not to buy in.

This will all become moot within the next weeks and months as units ship, are used, thoroughly tested, compared and the results shared.

Then we'll see how important optical encoders, GPS etc are, not to mention the elephant in the room many fail to talk about - the all important software that makes it all work.

Thank you,





Brian F Kobylarz said:
The proof will be in the products delivered.

With so many of the products converging to come to market within a relatively short time span of each other, it is perhaps a bit unfair to bait and challenge manufacturers to reveal too many details in advance of product release.

In much the same way as Jim Jannard learned with RED, his competitors absolutely loved it when he revealed too much too soon.

They are all so close, perhaps it is time to give everyone the opportunity to prepare their products for release without sideline speculation.
I think we can all pass the time with some anticipation, even healthy suspense as we approach the finish line.

To me, the best part is that with all the competition, everyone is working to build the best they can - and we are the beneficiaries - better products at lower costs.
Click to expand...
 
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