Hoping someone can help me here – I’m pretty sure it’s something quite simple and I tried some searches but to no avail.
I’ve already had a few successful flights with Pixhawk/Skywalker X-5 flying wing – in a park right next to my house. I decided to go to my local flying club today but I could not get the Pixhawk to arm (flashing yellow). In Mission Planner I looked at the Flight Data map and rest my mouse over the plane symbol and it shows 6Km to home. I then look at the Flight Plan tab and see the green “H” over my house!
So, it’s obvious that my home point has not been reset. Why is this? I’m sure I read somewhere that Pixhawk will record a new home point wherever it is powered up? I can only presume that the distance to home is what denied me the ability to arm because when I got home everything is fine.
When I was at the model club field I did try right click the plane symbol in the Flight Data map and selected “Set Home Here” but that did not help either.
Thanks in advance,
Sounds like you could use rally points.
Hi Stephen - that's the answer to my needs - thanks so much!
Still, it would be nice if the home point ambiguity in Plane could be resolved!
Before taking off, I always like to make sure my Pixhawk FC has the correct return to home GPS co-ordinates. Within the Mission Planner, there's an option (I can't remember right now), that you select to save the current coordinates directly to the flight controller, and then you can click on that option again, to read back the GPS coordinates so that, you can confirm if they are correct or not.
This has become part of my pre-flight check list.
Hi Francisco - please can you tell me where that option is in Mission Planner? This will be really useful to me especially during my practice/testing at my local model flying club. Right now, I have to take my plane and walk out into the long grass/mud away from the landing strip/pits area to acquire GPS in a location so that RTL is not circling over everyone's heads!
See here under the "Tips" section
Hi Mike - note that I was asking Francisco to explain how I can change the home point co-ordinates stored in the flight controller, as that is what he implies can be done.
I had seen the tips section you linked to, but all that does is re-set the Home location in Mission Planner. It does not allow me to reset the home point in the flight controller so that I am not circling over the pits and the flight line when I execute RTL.
Update: I thought I would also post my issue in the Plane user group, as I know there are a few subtle difference regarding home point acquisition between Plane and Copter.
I got a very useful reply from Michael Pede, as follows:
"Hey. The Home is tricky. It is also misleading. When you connect your tablet or PC at the field, and it reads the Home position before the GPS lock, it will give the Home position that was last valid.
When it DOES get a GPS lock, it will set the new Home location, but will NOT update your tablet. You need to disconnect and reconnect your telem after a new home is set.
As to why your home was once again set to home, perhaps you connecred your telem once it had armed, and the drift from your GPS lock inside a house caused it to jump to the other side of the house."
Also, I was fiddling again this morning and something interesting happened. The plane was sitting in my back garden (where GPS was acquired and still showing 30m or so to the home point in my workshop where it first acquired GPS after buying it). So I remove the SD card from the Pixhawk and suddenly the home point is where the model is sitting!
Am I just remembering this incorrectly? I thought home was reset to where the machine was last armed, not where it was powered up?
That's for 'Copter. In 'Plane its when it gets GPS lock. Presumably there is a good reason for the difference but someone else will have to tell you what it is.
Agreed - and the following is what the wiki (http://copter.ardupilot.com/wiki/common-planning-a-mission-with-way...) says:
"For Copter the home position is set as the location where the copter was armed. This means if you execute an RTL in Copter, it will return to the location where it was armed, so arm your copter in the location you want it to return to."
"For Plane the home position is the location of the plane where the GPS was locked. This means if you execute an RTL in Plane, it will return to the location where it first acquired the GPS lock, so only power up your plane in the location you intend it to return to when performing an RTL."
But what I find very confusing is the fact that there can dual home points insofar as Mission Planner and the flight controller are concerned. This is because as soon as you arm, Mission Planner re-sets it's record of the home location to the location of the arming. So if you moved your plane after it acquired GPS and arm it elsewhere then you get 2 versions of home and your distance to home will show differently in your OSD and Mission Planner, However, the actual home point the plane will return to in RTL (the important one!) is the one stored in your flight controller.
I actually read in one of the wikis that you can re-set the home point in Mission Planner by dragging the "H" (in the flight plan tab) to the location that your flight controller sees as home point. But this is really confusing and should be sorted out in my opinion. Unless someone can offer a valid reason as to why you would want a situation with 2 home points.
I was pretty annoyed before I knew of this issue, because I could not understand why the (actual) RTL location the plane flew to was not where Mission Planner was showing the "H" to be.