SB_0000008 Here4 magnetometer (Flight status Restored)

Mandatory Safety Bulletins
1

Edit 9th of July, 2024: All should please update your Here4 unit using Mission planner DroneCAN/UAVCAN panel, select download from the internet. Software Version should be 1.14.FE92DFEF or later. DO NOT UPDATE UBLOX FIRMWARE

This fixes an issue that can cause momentary loss of gps after 1 hour of use

Edit: 3rd of July: Flight status RESTORED. After much testing, it is confirmed that the failure mode is 100% predictable, and if it happens in flight, Ardupilot has no issues handling this. Testing with the here4 as a flight controller with no other assistance is underway, and we will update on the tests asap

Thanks to @sidbh and Paul Riseborough for their efforts in devising the tests to verify return to flight status.

This doesn’t mean your mag will not fail, but it does mean that if it happens in flight, it by itself will not be the cause of an accident.

This has occured to less than 0.1% of units.

Edit: 15th June 2024: we have 3 confirmed customers with this situation, all returned units labelled as faulty exhibit this failure mode. Break is not visible on 3D X-ray.

Firmware update has been issued for Here4, this will ensure the module behaves correctly in this failure mode.

Flight with Dual Here4 is acceptable (or any other backup magnetometer

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Here4 magnetometer issue under investigation.

Reports of magnetometer losses in Here4 have been reported to Cubepilot staff by a few customers now. We are unsure as to how widespread this issue is, as such we have put a hold on sales of Here4 GPS’s as of the 20th of May 2024.

We are investigating this matter at the moment to get a root cause and will add information to this bulletin as information comes to light.

In the meantime, please verify your magnetometer fallback on your vehicle, ensure you have effective redundancy to this sensor.

In the reported cases, once the error occurs, the mag never comes back. Thus preflight checks will prevent further flight. We will obviously replace any affected units, but replacements will only happen once we have a proper solution.

We appreciate your patience on this matter and apologise for the inconvenience this brings

Thanks
Philip and the Cubepilot team

3 Likes
2

Is this hardware related or software bug?
We have few Here3+ which have no magnetometer data coming out on bus monitor. Is this related?

3

Please raise an issue for your hardware in a thread for here3+, this is a here4 only thread, and as mentioned, still under investigation

4

Hi, is there any update on the Here 4 problem? We have been badly affected due to this issue as our sys were ready for delivery to our customer. The del has been stopped due to this prob appearing in atleast 4 units. Hope we can find some update, looking for gud news…
Regards

5

Hello @philip, do you think this could also affect the Here PRO?

6

All here pro units were built with an earlier bartch of magnetometers , so we are not concerned

7

Have you reported this? We can’t act if we don’t know about it. Who is your reseller? Where are the logs?

8

Yes, we have already reported the issue in cube pilot. Both you and @Cybra have also responded in the discussion. We bought 43 units of here 4 and the reseller is hex, china. We are looking for the way forward as our copter sys have been grounded.
Regards

9

RM3100 hardware issue? Or PCB design?

10

If this is an issue with a certain batch and later, why not give us the batch number so we can figure out if our unit have this issue?

1 Like
11

As soon as we can confirm we will.

At this point we have two customers with issues that are undergoing investigation. when we have further information, we will announce, until then, we are in a HOLD situation.

12

Hi Phillip,

Can you please reply the following:

1- Is this a design issue that so we can say that all units being manufactured and delivered this year 2024 may be affected, or instead is a particular manufacturing issue which affected only certain batches? In case this is a manufactured issue, is it possible to identify which batches may be affected?

2- What is the first symptom that the user will notice once the problem materialized?

3- Do we know already which operations condition are more prompt to materialize the problem?

13

3 of our Here4s started having this issue 2 weeks ago. Redundancy and fail-safes have prevented a crash sofar.
The only note I can add is that these incidents happened on the first project in warm weather. The units were working fine during winter time (Temps 0 to -20)
2 out of 3 malfunctioning Here4s showed some physical damage on the screw hole at the bottom. The plastic part holding the screw hole had came out and was broken in pieces. This made the cap of the Here4 to come loose on the top

1 Like
14

We will replace any here4 that has this issue as soon as we find a solution.

We do not have enough faulty units to determine if this is batch related yet.

Investigation is ongoing

1 Like
15

Edit: 15th June 2024: we have 3 confirmed customers with this situation, all returned units labelled as faulty exhibit this failure mode. Break is not visible on 3D X-ray.

Firmware update has been issued for Here4, this will ensure the module behaves correctly in this failure mode.

Flight with Dual Here4 is acceptable (or any other backup magnetometer

1 Like
16

Hi Philip,

just to be sure, after firmware update we can fly safely even if we have only one Here4, correct?

17

Only in a dual setup.

But all should please update your Here4 unit using Mission planner DroneCAN/UAVCAN panel, select download from the internet. Software Version should be 1.14.FE92DFEF .

This fixes an issue that can cause momentary loss of gps after 1 hour of use

18

Hi philip,
I have updated my Here4, but the version that appears is not the one you mention.

image
image998×448 38.5 KB

19

Hi, @philip
We have updated our here 4 units and they are working now… i wud like to ask that Dual setup u have been refering to is whether to provide redundancy or something else? If the testing has observed sudden gps loss after an hour or so, can we use a single here 4 for a sys that has flt time of less than an hour…
Awaiting reply
Regarda

20

i suggest to DL the latest version of Mission planner first, then retry. I tested with a Here4 and i have the same values Philip posted. (1.14.FE92DFEF)