XAircraft SuperX
- Thread starter envy
- Start date
That's the Best!
Companies like XA shouldn't have a contact page if they aren't going to respond, that just kills me.
I'll hit my dealer up again and maybe he can get them to give him an answer. I've tried this before with no joy, but I'll give it another go.
Sorry for venting, I'm just a little frustrated right now... but I'll survive
I've had many, most I have answered myself through experiment and the god folks help in forums like this one.
Right now I would like help understanding the BlackBox Data. They have a simple handout, but it doesn't explain all of the aspects of the data.
My most pressing concern at this point is hoe the "G" Value correlates to the settings in the GUI.
I know by reading the manual that the RC Gains will act upon the Attitude gains by 50% - 200%, and I get that, what I don't know is how to take the "G" Value from the BlackBox Data and translate that to a number that can be input into the GUI Gain settings.
In other words, once I tweak the gains using the RC Gains, I want to take the "G" Value and translate that to a number i.e. 1.5 that I can use in the GUI. Then I would zero Out the RC Gains and only use the GUI value.
I know that the SX "Remembers" the last setting of the RC gains and if you disconnect your channel 7 from the I/O or just disable the knob that the gains will be remembered, but in my opinion too many things can happen to make that scenario problematic, so I would prefer to hard code the gains in my GUI.
I could just go through the hassle of making my changes in the GUI and forget about the RC Gains altogether, but that wouldn't be utilizing a potentially good feature.
I haven't gotten an answer anywhere about this, and I think that a lot of people have assumptions as to what these values mean, but there hasn't been a definitive answer.
The people that should know the answer cold (XA), haven't provided a sufficient manual on the subject, nor have answered the question.
Thanks for the input!
Anthony
mediaguru
Member
While I can't say that G value of X equals a gui value of X, my interpretation has always been:
1. Work to make the GUI value the best overall number for basic flight. For me that's 1.2. Flies well in calm or wind.
2. Once #1 is done, G knob helps adjust for wind or changes in flight weight.
1. Work to make the GUI value the best overall number for basic flight. For me that's 1.2. Flies well in calm or wind.
2. Once #1 is done, G knob helps adjust for wind or changes in flight weight.
Av8Chuck
Member
I obviously didn't program the SX, but since no one that did chimes in on this forum I'll take a stab at your question. I don't see why the SX would be any different from most of the other controllers I've worked with, but all the flight controllers I've worked with use Proportional-Integral-Derivative, PID tuning, which is a control loop feedback mechanism. Some controllers like the Open Pilot CC provide you with the ability to change setpoints directly in real time in their GCS while others like DJI and the SX hide it under different GUI inputs and Tx Controls. Nevertheless your PID tuning.
If the PID controller parameters (the gains of the proportional, integral and derivative terms) are chosen incorrectly, the controlled process input can be unstable, i.e., its output diverges, with or without oscillation , and can cause instability by excess gain, particularly in the presence of significant lag. Generally, stabilization of response is required and the process must not oscillate for any combination of process conditions and setpoints, though sometimes marginal stability(bounded oscillation) is acceptable.
There are several methods for tuning a PID loop. The most effective methods generally involve the development of some form of process model, then choosing P, I, and D based on the dynamic model parameters. Manual tuning methods can be relatively complicated and inefficient which is why some companies only allow you to change one variable. The choice of variable will depend largely on whether or not the loop can be taken "offline" for tuning, and on the response time of the system. If the system can be taken offline, the best tuning method often involves subjecting the system to a step change in input, measuring the output as a function of time, and using this response to determine the control parameters.
So what does this mean to the SX and the knob on your TX? There are several methods for effecting the variables for PID tuning, the knob on the Tx could be adjusting the gain/strength of one feedback loop (the outer) to effect the sensitivity of the other (the inner), where the inner feedback loop represents basic flight commands and the outer represents attitude control that adjusts the "deadband" reducing the frequency of activation of the inner loop. Or it could be that the GUI sets the PI and the knob on your Tx changes the derivative in real time.
There are a lot of other ways that PID tuning can be accomplished, nevertheless, there are several good reason why XAircraft have not answered your question:
In either case the amount of gain represented by the "G" value from the Blackbox does not translate to a single number that can be entered into the GUI. Also, and probably more importantly to them, the way they answer your question would reveal what math their using which is a trade secrete (if such a thing exists in China...) Its really all just how the programers decided to implement the math.
If you don't understand or care about the math and want to visualize PID tuning, think about it in terms of two sets of three weights, one set is large and heavy and you can distribute them on your multirotor equally. You can adjust how far out from COG they go and how heavy they are. The big weights are represented by the gains that you're setting in the GUI. The heavier the weights and the farther out from COG the more docile or stable the MR. However, there are are physical limitation to your MR (a lot of variables) like prop size, KV and thrust. If you add too much weight (Gain), too far out from the GOC then you can easily get yourself into a flight condition where inertia overpowers thrust and you get the "Flip of DEATH." The knob on your Tx represents the second set of lighter weights, by positioning them relative to the heavier weights you can increase or decrease the response and the effectiveness of the the bigger weights. If you set these gains too high then you'll usually see the MR oscillate quickly. The heavy weights are used to setup you MR in ideal calm conditions, the lighter weights are for fine tuning, they can be moved relative to the heavy weights for changing conditions like higher density altitude, wind or a change in COG.
Although XAircraft has not answered your question to the satisfaction of most people, it does appear that there implementation of this type of proportional control is much better than DJI, or just about all of the controllers I've tried. The interesting and discouraging part of all this is that they don't seem to recognize this as their competitive advantage. DJI has implemented a lot of cool features that really appeal to users but they did so [in my opinion] on top of flawed math so you see a ton of bad press and YouTube video about "fly Away's" and "Flips of Death." If XAircraft would start to layer functionality on top their SX, or open it up and provide a developers API so we could add that functionality I think everyone might be surprised at how rapidly that development would progress.
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Av8Chuck
Member
What he said..
Hi Guys... WOW that's a lot of information, but I get it.
I am use to PID tuning, but as you mentioned, the SX uses a strategy for how we manage the gains that make it simpler for the end user, albeit with less specific control.
I have had an experience with 2 of my SXs whereby adjusting the RC gains would cause the FC to stop functioning. That's OK on the ground but unacceptable inflight.
I now believe part of the problem to be the improper setup of my endpoints on my Futaba 14SG, which I have now corrected.
After loosing an MR to this malady, I am reluctant to repeat the experience
For that reason, and my sense of security, I don't want to keep my RC Gains connected for normal flights and would prefer to make my final adjustments in the GUI, however what I'm hearing is that it may or may not be that simple. It may be that the coarse adjustment is achieved in the GUI and the fine tuning takes place on the TX... Or you may be able to achieve the same results through the GUI alone...
So if the same results can be achieved by making all of my adjustments via the GUI, then that would be my preference. I was just trying to use the RC Gains to help me determine the proper GUI settings easier than making an adjustment while connected to a PC, then flying, then landing and reconnecting to the PC, etc, etc...
BTW All of my previous flight tests with the SX were on light quadcopters and now I have an SX in a 1400mm octocopter that's AUW (with payload) is 40 lb. Quite a difference
At the default settings in the GUI of 1.0 the MR responds well to inputs, but doesn't like to maintain its position and is all over the place, which would be expected. Once the weather allows I will start with mediaguru's suggested starting point of at least 1.2, although I feel that it will require a higher setting in the final analysis.
Thanks for your input gentlemen and if anything I said doesn't ring true or you have further input, I appreciate all of your feedback!
Thanks... Anthony
I am use to PID tuning, but as you mentioned, the SX uses a strategy for how we manage the gains that make it simpler for the end user, albeit with less specific control.
I have had an experience with 2 of my SXs whereby adjusting the RC gains would cause the FC to stop functioning. That's OK on the ground but unacceptable inflight.
I now believe part of the problem to be the improper setup of my endpoints on my Futaba 14SG, which I have now corrected.
After loosing an MR to this malady, I am reluctant to repeat the experience
For that reason, and my sense of security, I don't want to keep my RC Gains connected for normal flights and would prefer to make my final adjustments in the GUI, however what I'm hearing is that it may or may not be that simple. It may be that the coarse adjustment is achieved in the GUI and the fine tuning takes place on the TX... Or you may be able to achieve the same results through the GUI alone...
So if the same results can be achieved by making all of my adjustments via the GUI, then that would be my preference. I was just trying to use the RC Gains to help me determine the proper GUI settings easier than making an adjustment while connected to a PC, then flying, then landing and reconnecting to the PC, etc, etc...
BTW All of my previous flight tests with the SX were on light quadcopters and now I have an SX in a 1400mm octocopter that's AUW (with payload) is 40 lb. Quite a difference
At the default settings in the GUI of 1.0 the MR responds well to inputs, but doesn't like to maintain its position and is all over the place, which would be expected. Once the weather allows I will start with mediaguru's suggested starting point of at least 1.2, although I feel that it will require a higher setting in the final analysis.
Thanks for your input gentlemen and if anything I said doesn't ring true or you have further input, I appreciate all of your feedback!
Thanks... Anthony
kloner
Aerial DP
if there is no g nob input your not doing it right. If changes makes it squirly you might try reducing the endpoint on that ch since your probably jumpting 10-50% a click.... my endpoints are set to 30 on g knob and moving it yields about 2-3% at a time, full deflection of the ch is like 60% gain, endpoints left alone it'll peg out really high
Yes, I had a bad experience, which is why I prefer not to use it on a regular basis, plus the fact that I don't have enough channels to keep it connected permanently anyway.
Anthony
SamaraMedia
Active Member
So I'm in the process of tearing down my 900mm UAP1 hex to upgrade from NAZA and Zenmuse H3-3D and intend to put a Super X I purchased off the forum a few months ago. I'm using KDE 2814 515kv motors, ZTW 45 amp ecs and 6s batteries. I have a T8FG with R6303SB or R6208SB. I'm building a Quadframe V2 gimbal so I can upgrade to 4:3 or DSLR rather than GoPro. Any known issues with motor and esc choice with SX? Everything has work real well with current setup but first time SX user.
Thanks,
Thanks,