Landing Inside a Giant Truck, Compass Problem

Cube Autopilot
2

2 RTK GNSS devices and heading from GPS (Arducopter 4.1)?

https://ardupilot.org/copter/docs/common-gps-for-yaw.html

Of course there a multipath issues. Probably not much better.

Can you put the sensor on a rope and avoid landing? Or use a rover on a rope for the measurements? Mars Rover style?

3

I would say never turn off any pre-arm check. It warns you for reason. It is always better to solve the warning than disabling it.

4

I understand, but i cant “solve the landingbay truck magnetic field”

What options do I have to avoid the magnetic field generated by the landing bay truck?

thanks

5

If the magnetic field is so strong that can’t be offset, maybe gps for yaw is an option.

6

Ok, I have check, seems to be a solution. Here 2 or 3 are compatible with this option? on the wiki only talck about this ones

imagen

7

hi!

I have seen the link, now I understand, thanks, I will look on to.

May be a rope with a magnet could work, we need some preasure over the thikness sensor, we need to try.

Thanks!

8

Go for an electro magnet.

I would recommend a GNSS module with a helical antenna. These patch antennas are not so great for RTK on board of drones from my personal experience. That is why EMLID moved from patch to helix.

There might be an issue with cycle slips if you fly into the bay. Then the whole gps-heading does not work. So its probably a good and cheaper idea to try the rope version first.

Don’t buy from C_UA_V, they copy from companies which are supporting Ardupilot.

1 Like
9

Here 2 and 3 are not compatible with gps for yaw. You will need HerePro.

1 Like
10

When will be the Here pro available ? And @Alvin I also need another help, that is I want to know what is RTK for Here GPS and which is the best GPS for my drone ? Here 1, Here 2, Here 3, Here Plus or Here Pro to get most stability and reliability in case of failsafe ?

11

HerePro will be available very soon.
Here+, Here3 and HerePro are RTK GPS.
Here3 and HerePro are relatively latest hardware so they are better.
There are no such best product because they have their strength and trade off. You should compare their specification to find out which one is most suitable for your requirement.

1 Like
13

Hi eveyone!

using RTK could help me fo avoid this problem?

Thanks!

14

I don’t think RTK is related. Your problem is about the vehicle’s heading while RTK helps to improve positioning.

15

What about duel GPS units for yaw?
There’s plenty of discussion going on over at Ardupilot.
The feature is still in Beta but should be available soon.

16

Thanks, I thougt may be help to improve the heading.

17

Hi @xfacta , you mean dual GPS? that will be different of this right?

https://ardupilot.org/copter/docs/common-gps-for-yaw.html

thanks

18

Hi

im trying to be creativeto solve this and avoid to spend more money on that drone, and I was wonder if the loiter mode can fly with a disabled compass?’

thanks!

19

According to the list, no. Loiter mode requires GPS lock.
https://ardupilot.org/copter/docs/flight-modes.html#gps-dependency

Edit: I think I may have misread compass as GPS. System won’t let you arm if there is no compasses. But you may have a look at this compassless operation.
https://ardupilot.org/copter/docs/common-compassless.html#gsf
I have not try this new feature but seems like it is acceptable. It uses IMU and GPS to estimate the yaw.

1 Like
20

Hi Alvin!

I have just did this and works great.

I have Some questions about this CompassLess method:

-It say: Before arming, but after GPS lock has been obtained and EKF origin has been set and is “using GPS”, pick up the vehicle and walk around in a circle a few meters in diameter
I did that but the error still there (Requires Position) until I did an AltHold flight for a few seconds, and then I could usue the Loiter Mode. So, Im not clear what method do I have to use to get the yaw, wich one is it, or a short flight or a wlak arround.

thanks!

21

You may want to ask this on Ardupilot forum as this is a software feature.
From what I understand from the wiki page, I think the Requires Position comes from GPS not getting fixed yet.
I think the idea is getting the vehicle moving around so the GSF can fuse the imu and GPS to get the yaw. Walking around is safer as you have disable some essential hardware (compass), but walking and flying should be doing the same thing.

22

great thanks!