RTH Features

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Seems to be a lot of confusion about different RTH scenarios. What is the setting I want that will allow me to return home by tracing the route? I sometimes fly at night and the Visual Sensors are a no go. Thanks
 
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I believe that the conclusion for this feature is: it only kicks in when a signal is lost. It is an attempt by the AC to backtrack to the point where signal can be reconnected. It is not a selectable feature vs the common elevate and beeline back home. That said, the CA for return to home has to be set under the RTH advanced setting and you are correct that it would be ineffective in poor or no light.


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I believe that the conclusion for this feature is: it only kicks in when a signal is lost. It is an attempt by the AC to backtrack to the point where signal can be reconnected. It is not a selectable feature vs the common elevate and beeline back home. That said, the CA for return to home has to be set under the RTH advanced setting and you are correct that it would be ineffective in poor or no light.


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Thanks. My one concern about the common elevate and beeline back home, if you set it with CA you have no control of the bird at all..I understand that makes sense, if its tracking back it doesn't need the pilot mucking it all up.
 
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Actually I use the RTH function not long after I take off the drone. This is to make sure that if I have lost signal it will fly back. Sometimes when the drone is out of sight and when I m too lazy, I use the RTH function also until the drone is near to me


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What is the setting I want that will allow me to return home by tracing the route?
This is supposed to automatically engage if the obstacle sensors are enabled. I attempted to reproduce this behavior yesterday (in a wide open location) and I couldn't do it. My Phantom returned straight back to the home point every time. I'm assuming there is some kind of built in logic that will only retrace the flight path when you lose the remote controller signal near obstacles. Unfortunately, DJI does not have documentation of this feature anywhere.
 
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This is supposed to automatically engage if the obstacle sensors are enabled. I attempted to reproduce this behavior yesterday (in a wide open location) and I couldn't do it. My Phantom returned straight back to the home point every time. I'm assuming there is some kind of built in logic that will only retrace the flight path when you lose the remote controller signal near obstacles. Unfortunately, DJI does not have documentation of this feature anywhere.
In your testing I am assuming you turned off the RC to force the RTH vs pressing RTH. Interesting, I too was considering that the logic may be mapping the path during flight for obstacles, and in the absence of any it would take the return path of least resistance. Do you believe that too?


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That would make sense. Without creating a risk to the AC, it would be useful to repeat the test with a line of trees or like obstacles that would clearly be seen as a solid barrier by the AC. Given my understanding, I would think it would react as expected and retrace for a time of x before it elevated and beelined home.


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Thanks. My one concern about the common elevate and beeline back home, if you set it with CA you have no control of the bird at all..I understand that makes sense, if its tracking back it doesn't need the pilot mucking it all up.
So long as you have connection to the drone you can cancel the RTH and retake control.
 
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This is supposed to automatically engage if the obstacle sensors are enabled. I attempted to reproduce this behavior yesterday (in a wide open location) and I couldn't do it. My Phantom returned straight back to the home point every time. I'm assuming there is some kind of built in logic that will only retrace the flight path when you lose the remote controller signal near obstacles. Unfortunately, DJI does not have documentation of this feature anywhere.
How did you do the test with loss of TX connection? Did you turn off the TX? Or did you fly the drone out of LOS so it was an actual TX communication lost? In my testing, the backtrack only works with the latter. Turning off the TX initiated a normal RTH. It appears that the system is somehow "smart" enough to know that you simply turned off the TX and thus initiates a standard RTH.


edit: here's a video of the backtrack working

 
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Clearly these things are very smart and getting better with every generation. Nice example of trackback vs failsafe RTH.
 

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backtrack only works with the latter. Turning off the TX initiated a normal RTH.
Yes, that seems to be the case. Here's an example of what happened when I caused the remote controller signal to drop by blocking it:

RthTest.jpg


The short straight line near the end of the flight is just due to missing data since the downlink was lost between those two points. The Phantom should have kept flying along the original path. As you can see though, the route back does not follow the path exactly. With obstacle avoidance enabled though, that shouldn't matter since the Phantom would correct itself if there were obstacles in its path.
 
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Yes, that seems to be the case. Here's an example of what happened when I caused the remote controller signal to drop by blocking it:

View attachment 71828

The short straight line near the end of the flight is just due to missing data since the downlink was lost between those two points. The Phantom should have kept flying along the original path. As you can see though, the route back does not follow the path exactly. With obstacle avoidance enabled though, that shouldn't matter since the Phantom would correct itself if there were obstacles in its path.
That's interesting. Without OA enabled it appears you could get into trouble and crash during return, since it doesn't actually follow the exact path. Seems like that could be a liability if you're out having a good time in sport mode and lose connection. Am I wrong?
 

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RTH will not retrace the previous path if OA is disabled.
 
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This is supposed to automatically engage if the obstacle sensors are enabled. I attempted to reproduce this behavior yesterday (in a wide open location) and I couldn't do it. My Phantom returned straight back to the home point every time. I'm assuming there is some kind of built in logic that will only retrace the flight path when you lose the remote controller signal near obstacles. Unfortunately, DJI does not have documentation of this feature anywhere.
Not to mention none of the sensors work at night.
 
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That's interesting. Without OA enabled it appears you could get into trouble and crash during return, since it doesn't actually follow the exact path. Seems like that could be a liability if you're out having a good time in sport mode and lose connection. Am I wrong?
Sport mode in and of itself will not disable OA sensors during backtrack and RTH, it auto goes into P mode. I tested this. Disabling the OA sensors manually however, will disable OA during RTH and as msinger stated it will not backtrack at all with OA sensors disabled.
 
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To whom it may concerned...

I am new to the drone world, and want to utilize the expertise of others as well as learn from my good and bad experiences.

first of all, I would like to know if the Phantom 4 landing gear extensions will fir on the Phantom 4 Pro?
 

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