Multiple choice RTH question

[pauxier]

Which path will a P4P take when the RTH button is pushed? Red, Green, or Blue?

 

[msinger]

Red

 

[joet]

Green. If in a signal loss RTH, it will backtrack the way it came until it regains signal, at which point it will go straight-link RTH. However, since RTH was initiated with the button, signal must exist, and thus straight-line RTH.

 

[msinger]

Green. If in a signal loss RTH, it will backtrack the way it came until it regains signal, at which point it will go straight-link RTH.

You're looking at this diagram incorrectly. Green is showing the Phantom making a bee line back to the home point. It will never do that.

 

[dirkclod]

Well a P4P is different than I have ever seen . No matter what it would come back Red

Added/ sorry singer we hit at same time

 

[smiller]

Green is showing the Phantom making a bee line back to the home point. It will never do that.

I'm confused, that's exactly what it will do (beeline home, after first climbing to RTH altitude) if the manual RTH button is pressed. Why would it dog leg like the red line?

If signal is lost it will first backtrack for a certain distance, then beeline RTH if contact is not reestablished. But that was not the scenario outlined in the OP.

But the diagram is confusing, which color (if any) is the original outbound leg?

 

[pauxier]

I hadn't thought of this possibility

 

[Alex Baxter]

Green. If in a signal loss RTH, it will backtrack the way it came until it regains signal, at which point it will go straight-link RTH. However, since RTH was initiated with the button, signal must exist, and thus straight-line RTH.

I think it's a vertical profile (even though the bird is side on), so RED, it'll always come home at the altitude that RTH was pressed, unless the RTH point is lower that the set RTH altitude, in which case it'll rise to the RTH altitude before setting off home..

 

[msinger]

I'm confused

Yes -- this is a confusing diagram if you don't look at it correctly.

 

[pauxier]

I assumed that if you have a RTH value set and you are lower than that, it would rise first then travel home. It got me thinking about being above the set value, and would it lower immediately then return or something else. Hard to explain, that's why I tried to diagram (might have made it worse)

 

[smiller]

Green is showing the Phantom making a bee line back to the home point. It will never do that.

But why do you say that the P4P will never beeline back home if RTH is requested(?) That is exactly what it will do.

Edit: Oh wait, I got it. It is an altitude diagram, not horizontal.

 

[msinger]

Bingo

 

[Mr. Salty]

Yes -- this is a confusing diagram if you don't look at it correctly.

People are looking at it incorrectly because it's a confusing diagram!

As illustrated, it's from above because of the silhouette of the Phantom. But the intent apparently is for it to be seen as a side view. And if that's the case and your Phantom is on its side it's never going to make it back to the home point as it plunges to the ground!

But, if we go by the apparent intent of the diagram, the correct answer is red. The Phantom will ascend to the set RTH height unless it is already above that set height. It will then maintain its current height until it is over the home point, then it will descend.

Unless you're using the current version of the DJI Go app on an Android device. Then the Phantom could land a couple of miles from the home point unless it runs out of battery before it gets there.

 

[joet]

You're looking at this diagram incorrectly. Green is showing the Phantom making a bee line back to the home point. It will never do that.

I was looking at it in the wrong axis - i.e. From the top instead of the side. Yes, if the P4 (and any P3, P4, Mavic, as I understand it) engages RTH above the RTH set altitude, it will proceed at that altitude to the home point and land.

Exception: If it is within a certain distance - 25', I think? - it will simply land on RTH.

 

[pauxier]

I tried to fix the diagrams a bit, sorry for the confusion and thanks for the info. I am going to test this soon and I hope it is red!

 

[joet]

Mo

I tried to fix the diagrams a bit, sorry for the confusion and thanks for the info. I am going to test this soon and I hope it is red!

No need to worry, it is absolutely red. If RTH initiates for any reason below RTH altitude, it will climb to RTH. If it is above RTH altitude, it will proceed home at that altitude. It will NEVER descend until it is over the home point and landing.

Now for the P4 - with obstacle avoidance - if it detects an obstacle in its path, it will climb to avoid the obstacle. So it can ASCEND if needed, but will never DESCEND.

 

[Meta4]

I assumed that if you have a RTH value set and you are lower than that, it would rise first then travel home. It got me thinking about being above the set value, and would it lower immediately then return or something else. Hard to explain, that's why I tried to diagram (might have made it worse)

Your Phantom is programmed to come back at or above RTH but it will never descend to RTH.