Follow Me Erratic Behaviour

[mikeve]

Hi Gang

Had a search and couldn't find anything similar...

First try at the Follow-Me mode. Set it up and activated it looking (sort of) at me. Moved sideways and it seemed to follow OK. I turned in the direction I was moving and the bird sort of shook itself like a wet dog and accelerated past me without pivoting. Reset to Atti then GPS mode and all was well. gave it another try and the same thing happened. It seemed more like "Tag, you're it" than "Follow me".

Any ideas? Here is the HD report.

HealthyDrones.com - Innovative flight data analysis that matters

I will upload the relevant video in a bit.

Many thanks.

Mike V.

 

[Mark The Droner]

Sounds like a bad fix on your device

 

[mikeve]

Here's the video...

 

[mikeve]

How can I tell? I was using an iPhone 6 in a very open space.

 

[Ken62465]

With firmware 1.7.6 installed I noticed this same thing today. The P3A shook in place multiple times, finally said "F this" and exited. It did not do this with firmware 1.6.4. Seemed like when I stop moving it freaked out.

I also noticed with the new firmware the "Homepoint" quick access icon is gone..ha? I had to access it from drop down menu. That sucks but why would they remove it? Course I'm only a few weeks old on the thing so maybe I'm missing something.

 

[mikeve]

I just upgraded too. And I don't think you can properly exercise the feature in the simulator.

 

[Ken62465]

lol..never tried follow me in the simulator...that even sounds f'd up..lol. Can you even do that? Simulator and run around with the remote? I'm sorry I'm just chuckling at the thought...all in good fun.

I want to correct the second part of what I said. Firmware has nothing to do with the icon being removed, that was goof on my part. I believe the DJI Go app updated on me and the latest version seems to have removed the icon for "Homepoint"...that bites because I like quick access to it for things I do.

 

[Ken62465]

I watched your video. Your first post said "shook itself like a wet dog" yet the video seemed to do a flyaway. I did not experience this myself but the shook like a wet dog I absolutely did...3 times to be exact. It did it every time I moved and then stopped. It was like it was shaking it's fist at me for stopping and didn't do that with 1.6.4 firmware. Might test again again tomorrow....all was normal until I stopped.

 

[mikeve]

The shaking wasn't all that evident in the vide. It flew away at full speed immediately afterwards. I stopped it by switching to GPS right away.

First time I'd tried follow me.

 

[Sagebrush]

How can I tell? I was using an iPhone 6 in a very open space.

An iPhone will not allow an app to access the GPS/GLONASS chip so there's no way to tell how many satellites... but you had plenty of horizon so I just can't believe it was a bad fix with your device. The only real way to check the "fix" is to confirm the blue GPS dot on the phone appears to be accurate.

Are you sure the GPS was turned on in the iPhone or it wasn't in Airplane Mode?

Sagebrush

 

[mikeve]

The blue dot was in the right place.

 

[BudWalker]

Hi Gang

Had a search and couldn't find anything similar...

First try at the Follow-Me mode. Set it up and activated it looking (sort of) at me. Moved sideways and it seemed to follow OK. I turned in the direction I was moving and the bird sort of shook itself like a wet dog and accelerated past me without pivoting. Reset to Atti then GPS mode and all was well. gave it another try and the same thing happened. It seemed more like "Tag, you're it" than "Follow me".

Any ideas? Here is the HD report.

HealthyDrones.com - Innovative flight data analysis that matters

I will upload the relevant video in a bit.

Many thanks.

Mike V.

The problem you had may be related to similar incident that was reported here Testing Follow me-mode, fly away and crash :(
and for the next several posts.

There is a difference though. Apparently your problem didn't occur precisely when you engaged Follow Me. Never the less I'd like to look at your .DAT if you could provided it. Look here to see how to retrieve the .DAT. It'll be large; can you post it via Dropbox or equivalent.

 

[mikeve]

HI Gang

A little more info from the test yesterday. The first time I tried FM function it worked for 15 seconds before is shook and then it took off. the second time, it shook and then took off immediately.

Tried it again today. No fly-away tendencies, but the shake was there. I found out that it shakes "like a wet dog" when my iPhone tilts enough to trigger the display rotation. Normally, looking at the display in landscape mode (wide), the top is the top. When I let the remote hang on the neck strap, the remote tilts enough to force the iPhone to rotate the display 180 so that the top is at the bottom, if you know what I mean.

The fly-aways from yesterday are still unexplained.

 

[mikeve]

The problem you had may be related to similar incident that was reported here Testing Follow me-mode, fly away and crash :(
and for the next several posts.

There is a difference though. Apparently your problem didn't occur precisely when you engaged Follow Me. Never the less I'd like to look at your .DAT if you could provided it. Look here to see how to retrieve the .DAT. It'll be large; can you post it via Dropbox or equivalent.

BudWalker, I have sent you a PM with a DB link. Many thanks for your help.

 

[Sagebrush]

when my iPhone tilts enough to trigger the display rotation

Curious deal. Glad you figured out....

S

 

[Mark The Droner]

Water is an efficient block of GPS and our bodies are made of water. For that reason, I would not want to hang my device from my neck and allow it to be so close to me while in Follow Me. I would want to hold the device out just a bit so that it has access to as many satellites as possible.

 

[BudWalker]

BudWalker, I have sent you a PM with a DB link. Many thanks for your help.

As I mentioned there have been a few incidents lately where the initiation of Follow Me coincides with an abrupt change of where the P3 thinks the tablet is located. You had one of those. But, you also had another incident where the disruption in tablet location wasn't related to Follow Me initiation.

This plot shows tabletLongitude and flyCState(blue line); flyCState=25 indicates FollowMe mode.

The second disruption at time 956 occurs exactly when FollowMe mode is initiated. I've speculated that this is not an actual change in the lat-long coordinates generated by the tablet's GPS. Rather, it's a bug of some kind that presents itself when inititiating FollowMe mode. @AndersGB has determined that the coordinates coming from the tablets GPS are correct. See Testing Follow me-mode, fly away and crash :( and the next several posts for more info in this.

The first disruption at time 924 looks like a random event caused by an actual change in the tablet's GPS. See @Marknmd 's post immediately preceding this post.

Just for fun I plotted the tabletLongitude and velocity.

It shows that after the first, smaller, disruption the P3 started flying away. After the second, larger, disruption the P3 flew away much faster.

 

[mikeve]

This plot shows tabletLongitude and flyCState(blue line); flyCState=25 indicates FollowMe mode.
View attachment 47980

Wow! Great analysis! I will do the same sort of look at yesterday's flight that showed the shaking when to app display flipped.

Interesting... I was just looking at the replay in the DJI Go app and, for the first fly-away, the bird yawed to keep pointing at me. It's as if one part of the app knew where I was and the other part didn't. Further, the blue dot didn't jump at all.

Thanks again for a great analysis.

 

[AndersGB]

Wow! Great analysis! I will do the same sort of look at yesterday's flight that showed the shaking when to app display flipped.

Interesting... I was just looking at the replay in the DJI Go app and, for the first fly-away, the bird yawed to keep pointing at me. It's as if one part of the app knew where I was and the other part didn't. Further, the blue dot didn't jump at all.

Thanks again for a great analysis.

The same for me, the blue dot (= the RC/tablet) had the correct position in the replay all the time. That's why I got suspicious and wanted to look at my accident deeper.