# Questions regarding RB5 5G drone

Source: https://forum.modalai.com/topic/823/questions-regarding-rb5-5g-drone
Category: Development Drones (https://forum.modalai.com/category/44/development-drones)
Tags: rb5
Posted: 2022-03-29 20:04:31 UTC by MJ
Replies: 25 · Views: 7227

## MJ · 2022-03-29 20:04:31 UTC

I would kindly ask you to provide some information:

1) I have updated the SDK to the latest version (1.1.3), successfully (according to the online instructions, including re-enabling all the services).
After the update, I'm not able to connect to the QCG (it was operational prior to the update). 
Looking to the config file / script /etc/modalai/full-m0052.config, seems this file was changed after the update, and now is using the find-qgc-address command. When I try to use this command from the command line, it provides no response (NULL). 

When I executed following commands, the result is as follows:
root@qrb5165-rb5:~# systemctl enable rb5-px4-start

root@qrb5165-rb5:~# systemctl status rb5-px4-start
 ● rb5-px4-start.service - rb5-px4-start
   Loaded: loaded (/etc/systemd/system/rb5-px4-start.service; enabled; vendor preset: enabled)
   Active: inactive (dead)

The same status (inactive) is also shown after the reboot.

Could you please advise how to configure the system to connect to QCG, as current instruction do not provide updated info?

2) How to configure output RTSP video stream from cam3? Currently we're receiving 640x480@30 fps, but would like to use full 4k.

3) I ordered Pro Dev Kit w/ 5G. It arrived with DX 6e RC. Seems the RC is paired with the receiver, since the receiver LED is lit still orange (when the transmitter is turned on). But we're unable to arm the drone according to the online guide (https://docs.modalai.com/Qualcomm-Flight-RB5-user-guide-pre-flight-setup/  and https://docs.modalai.com/Qualcomm-Flight-RB5-user-guide-first-flight/).
Could you please advise what is Aux2 Gov switch, since it is placed on ch7, and our transmitter has only 6 channels? Could you please provide short instructions how to configure the RC and the RX?

![c9a3b428-851c-46d9-b1d5-271d1d8f694c-image.png](https://forum.modalai.com/assets/uploads/files/1648583856203-c9a3b428-851c-46d9-b1d5-271d1d8f694c-image.png)

## Reply by Guest · 2022-03-29 20:46:20 UTC

Hi @MJ , 

I hope all is well! 

A good indicator to follow is that the ESC blue LEDs flash at the bottom of the drone when PX4 starts up. If there is an issue and rb5-px4-start service doesn't start, then we will see no blue LEDs flashing. 

If you would like to set a specific QGC IP you can set it here and PX4 picks it up at start-up: 

![d353e3ba-e21e-446a-a2ce-4477eaedbe3a-image.png](https://forum.modalai.com/assets/uploads/files/1648585980555-d353e3ba-e21e-446a-a2ce-4477eaedbe3a-image.png) 

By the way, what is your console output when you run ```px4-versions``` ? 

Did you update your Wifi settings? PX4 needs a working network interface with IP address. 

Did you update the netcheck service as well for Wifi, such as wlan0, in this case it shows eth1 on 192.168 subnet: 
![63083a7c-712c-4bf1-a8bd-6f9c84d64bfa-image.png](https://forum.modalai.com/assets/uploads/files/1648586170326-63083a7c-712c-4bf1-a8bd-6f9c84d64bfa-image.png) 

Regarding the video stream or rb5-streamer, I believe the resolution is fixed. I'm unsure the full 4K could stream, but may only be able to saved to file at such a high resolution. 1080p should work I believe. I could look into releasing source code for modification if helpful. 

And regarding RC channels, you can get by with 6 channels. The 7th channel in the example is for the kill switch, which is helpful in some cases: https://docs.modalai.com/Qualcomm-Flight-RB5-user-guide-pre-flight-setup/
You can have all your main flight modes on channel 5 then have the kill switch or another function on channel 6 by using this QGC menu:

![367e4621-09aa-4eaf-bca7-4d52dd25b203-image.png](https://forum.modalai.com/assets/uploads/files/1648586632954-367e4621-09aa-4eaf-bca7-4d52dd25b203-image.png)

## Reply by Chad Sweet (ModalAI staff) · 2022-03-30 15:46:07 UTC

The RTSP streaming capabilities will heavily depend on network capacity. The QRB5165 is capable of encoding 8k30, but that is a lot of bandwidth.

To configure different streaming capabilities, disable the rb5-streamer service and use gstreamer on your own. The rb5-streamer app was based off of the code found [here](https://github.com/quic/sample-apps-for-Qualcomm-Robotics-RB5-platform/tree/master/Gstreamer-Applications)

## Reply by MJ · 2022-03-30 19:24:36 UTC (in reply to Guest)

@RichieRich 
Thank you for your excellent advice.

I will try to explain my current configuration. For local testing and configuration I'm using ADB and local WLAN. For final application I would like to use 5G network. 
Of course, I need VPN (and will use OpenVPN) to provide connection between the ground station and the drone. For OpenVPN server I'm using some Mikrotik appliance configured to provide fixed, predefined IP addresses to GC and the drone.
Ground Control always receives 192.168.88.20
Drone always receives 192.168.88.21
Both are mutually "visible" and can communicate. This is working without issues.

In regard to your first question, here is the result of
sh-4.4# **px4-versions**
modalai-slpi/unknown,now 1.0-6 arm64 [installed]
px4-rb5-flight/unknown,now 1.4-6 arm64 [installed]
px4-support/unknown,now 1.0-4 arm64 [installed]
libfc-sensor/unknown,now 1.0-2 arm64 [installed]
1.0.5-M0052-9.1-perf

Here is the result of ifconfig on the drone. wwan0 is the 5G connection, tun0 is the OpenVPN connection tunnel.

sh-4.4# ifconfig
bond0: flags=5123<UP,BROADCAST,MASTER,MULTICAST>  mtu 1500
        ether 7a:19:6d:34:23:5d  txqueuelen 1000  (Ethernet)
        RX packets 0  bytes 0 (0.0 B)
        RX errors 0  dropped 0  overruns 0  frame 0
        TX packets 0  bytes 0 (0.0 B)
        TX errors 0  dropped 0 overruns 0  carrier 0  collisions 0

dummy0: flags=195<UP,BROADCAST,RUNNING,NOARP>  mtu 1500
        inet6 fe80::98d0:c594:6a01:f80a  prefixlen 64  scopeid 0x20<link>
        ether d6:41:ed:11:b0:d3  txqueuelen 1000  (Ethernet)
        RX packets 0  bytes 0 (0.0 B)
        RX errors 0  dropped 0  overruns 0  frame 0
        TX packets 13  bytes 3394 (3.3 KB)
        TX errors 0  dropped 0 overruns 0  carrier 0  collisions 0

lo: flags=73<UP,LOOPBACK,RUNNING>  mtu 65536
        inet 127.0.0.1  netmask 255.0.0.0
        inet6 ::1  prefixlen 128  scopeid 0x10<host>
        loop  txqueuelen 1000  (Local Loopback)
        RX packets 60750  bytes 10831838 (10.8 MB)
        RX errors 0  dropped 0  overruns 0  frame 0
        TX packets 60750  bytes 10831838 (10.8 MB)
        TX errors 0  dropped 0 overruns 0  carrier 0  collisions 0

**tun0:** flags=4305<UP,POINTOPOINT,RUNNING,NOARP,MULTICAST>  mtu 1500
        inet **192.168.88.21**  netmask 255.255.255.0  destination 192.168.88.21
        inet6 fe80::b41d:2608:5fb4:fcc5  prefixlen 64  scopeid 0x20<link>
        unspec 00-00-00-00-00-00-00-00-00-00-00-00-00-00-00-00  txqueuelen 100  (UNSPEC)
        RX packets 59  bytes 7414 (7.4 KB)
        RX errors 0  dropped 0  overruns 0  frame 0
        TX packets 96  bytes 18438 (18.4 KB)
        TX errors 0  dropped 0 overruns 0  carrier 0  collisions 0

wlan0: flags=4099<UP,BROADCAST,MULTICAST>  mtu 1500
        ether 00:03:7f:12:a2:e9  txqueuelen 3000  (Ethernet)
        RX packets 0  bytes 0 (0.0 B)
        RX errors 0  dropped 0  overruns 0  frame 0
        TX packets 0  bytes 0 (0.0 B)
        TX errors 0  dropped 0 overruns 0  carrier 0  collisions 0

**wwan0:** flags=4305<UP,POINTOPOINT,RUNNING,NOARP,MULTICAST>  mtu 1430
        inet 10.194.65.175  netmask 255.255.255.224  destination 10.194.65.175
        unspec 00-00-00-00-00-00-00-00-00-00-00-00-00-00-00-00  txqueuelen 1000  (UNSPEC)
        RX packets 14127  bytes 18472229 (18.4 MB)
        RX errors 0  dropped 0  overruns 0  frame 0
        TX packets 1408  bytes 110804 (110.8 KB)
        TX errors 7  dropped 0 overruns 0  carrier 0  collisions 0

I have placed following configuration in **/etc/systemd/system/rb5-net-check.service**
[Unit]
Description=rb5-net-check
#After=sscrpcd.service *---> this is commented*
After=openvpn.service *---> I wait for openvpn to start*
Requires=sscrpcd.service

[Service]
Type=oneshot
ExecStart=/usr/bin/rb5-net-check **tun0 192.168**
RemainAfterExit=yes

[Install]
WantedBy=multi-user.target

Also I have added the IP 192.168.88.20 to the /etc/modalai/qgc-ip.cfg.

The result of 
sh-4.4# **rb5-net-check tun0**
192.168.88.21

is as expected, ok.

But I have issue with PX4. I am not sure what to do here (also the blue LEDs do not blink, as it was before the update).

sh-4.4# systemctl status rb5-px4-start
● rb5-px4-start.service - rb5-px4-start
   Loaded: loaded (/etc/systemd/system/rb5-px4-start.service; enabled; vendor pr
   Active: failed (Result: exit-code) since Wed 2022-03-30 18:58:41 UTC; 4min 46
  Process: 2671 ExecStart=/bin/bash -c PATH=/usr/bin m0052-px4 -d (code=exited,
 Main PID: 2671 (code=exited, status=134)

sh-4.4# systemctl enable rb5-px4-start
sh-4.4# systemctl status rb5-px4-start
● rb5-px4-start.service - rb5-px4-start
   Loaded: loaded (/etc/systemd/system/rb5-px4-start.service; enabled; vendor pr
   Active: failed (Result: exit-code) since Wed 2022-03-30 18:58:41 UTC; 5min ag
 Main PID: 2671 (code=exited, status=134)

Mar 30 18:58:33 qrb5165-rb5 systemd[1]: Started rb5-px4-start.
Mar 30 18:58:41 qrb5165-rb5 bash[2671]: terminate called after throwing an insta
Mar 30 18:58:41 qrb5165-rb5 bash[2671]:   what():  FATAL: could not find sensors
Mar 30 18:58:41 qrb5165-rb5 bash[2671]: /usr/bin/m0052-px4: line 18:  2672 Abort
Mar 30 18:58:41 qrb5165-rb5 systemd[1]: rb5-px4-start.service: Main process exit
Mar 30 18:58:41 qrb5165-rb5 systemd[1]: rb5-px4-start.service: Failed with resul

When I start the QGroundControl, I can receive the video from the drone without any issues (as it is independent from CC link).

Could you provide some idea how to debug and resolve the issues with PX4? Many thanks!

## Reply by MJ · 2022-03-30 19:27:07 UTC (in reply to Chad Sweet)

@Chad-Sweet Thank you, will try this soon.

## Reply by MJ · 2022-03-30 21:28:00 UTC (in reply to MJ)

Since some text was missing, I have attached the complete dump here:

root@qrb5165-rb5:~# **systemctl status rb5-px4-start**
● rb5-px4-start.service - rb5-px4-start
   Loaded: loaded (/etc/systemd/system/rb5-px4-start.service; enabled; vendor preset: enabled)
   Active: failed (Result: exit-code) since Wed 2022-03-30 21:14:17 UTC; 11min ago
 Main PID: 2320 (code=exited, status=134)

Mar 30 21:14:08 qrb5165-rb5 systemd[1]: Started rb5-px4-start.
Mar 30 21:14:17 qrb5165-rb5 bash[2320]: terminate called after throwing an instance of 'std::runtime_error'
Mar 30 21:14:17 qrb5165-rb5 bash[2320]:   what():  FATAL: could not find sensors QMI service
Mar 30 21:14:17 qrb5165-rb5 bash[2320]: /usr/bin/m0052-px4: line 18:  2321 Aborted                 px4 $DAEMON -s /etc/modalai/full-m0052.config
Mar 30 21:14:17 qrb5165-rb5 systemd[1]: rb5-px4-start.service: Main process exited, code=exited, status=134/n/a
Mar 30 21:14:17 qrb5165-rb5 systemd[1]: rb5-px4-start.service: Failed with result 'exit-code'.

Here is the  full-m0052.config (unedited, from January 2022)
https://pastebin.com/j5WNgF5Q

## Reply by Eric Katzfey (ModalAI staff) · 2022-03-30 22:50:26 UTC (in reply to MJ)

@MJ Can you disable the startup service? ```systemctl disable rb5-px4-start``` and then reboot. Then, adb into the RB5 and launch px4 from the command line ```m0052-px4``` and paste the output of that here. That should tell us more information about what is going wrong.

## Reply by MJ · 2022-03-31 07:33:41 UTC (in reply to Eric Katzfey)

@Eric-Katzfey 

Please find the output here:
![c99cb244-8078-428a-87ea-71be0c47fc45-image.png](https://forum.modalai.com/assets/uploads/files/1648712154046-c99cb244-8078-428a-87ea-71be0c47fc45-image.png) 
```
root@qrb5165-rb5:~# m0052-px4
INFO  [px4] mlockall() enabled. PX4's virtual address space is locked into RAM.
INFO  [px4] assuming working directory is rootfs, no symlinks needed.

______  __   __    ___
| ___ \ \ \ / /   /   |
| |_/ /  \ V /   / /| |
|  __/   /   \  / /_| |
| |     / /^\ \ \___  |
\_|     \/   \/     |_/

px4 starting.

INFO  [px4] Calling startup script: /bin/sh /etc/modalai/full-m0052.config 0
terminate called after throwing an instance of 'std::runtime_error'
  what():  FATAL: could not find sensors QMI service
/usr/bin/m0052-px4: line 18:  5180 Aborted                 px4 $DAEMON -s /etc/modalai/full-m0052.config
```

I tried this several times, every time exact the same message.

## Reply by Eric Katzfey (ModalAI staff) · 2022-03-31 16:47:53 UTC (in reply to MJ)

@MJ There should be a program called ```ssc_sensor_info```. Can you run that and paste the output of that here? Also the output of ```ls -l /usr/lib/libs*```?

## Reply by MJ · 2022-03-31 16:56:53 UTC (in reply to Eric Katzfey)

@Eric-Katzfey 

```
sh-4.4# ls -l /usr/lib/libs*
-rw-r--r-- 1 root root     4010 Oct 27  2015 /usr/lib/libsafe_iop.a
lrwxrwxrwx 1 root root       18 Oct 27  2015 /usr/lib/libsafe_iop.so -> libsafe_iop.so.0.3
lrwxrwxrwx 1 root root       18 Oct 27  2015 /usr/lib/libsafe_iop.so.0 -> libsafe_iop.so.0.3
-rw-r--r-- 1 root root     9976 Oct 27  2015 /usr/lib/libsafe_iop.so.0.3
-rwxr-xr-x 1 root root   231664 Dec  6 21:46 /usr/lib/libsdsprpc.so
lrwxrwxrwx 1 root root       22 Dec  6 21:59 /usr/lib/libsensorslog.so -> libsensorslog.so.1.0.0
lrwxrwxrwx 1 root root       22 Dec  6 21:59 /usr/lib/libsensorslog.so.1 -> libsensorslog.so.1.0.0
-rwxr-xr-x 1 root root     5648 Dec  6 21:47 /usr/lib/libsensorslog.so.1.0.0
-rwxr-xr-x 1 root root    42840 Dec  6 21:49 /usr/lib/libsimple_selectors.so
lrwxrwxrwx 1 root root       19 Dec  6 21:59 /usr/lib/libsns_api.so -> libsns_api.so.0.0.0
lrwxrwxrwx 1 root root       19 Dec  6 21:59 /usr/lib/libsns_api.so.0 -> libsns_api.so.0.0.0
-rwxr-xr-x 1 root root    22104 Dec  6 21:47 /usr/lib/libsns_api.so.0.0.0
lrwxrwxrwx 1 root root       35 Dec  6 21:59 /usr/lib/libsns_direct_channel_stub.so -> libsns_direct_channel_stub.so.1.0.0
lrwxrwxrwx 1 root root       35 Dec  6 21:59 /usr/lib/libsns_direct_channel_stub.so.1 -> libsns_direct_channel_stub.so.1.0.0
-rwxr-xr-x 1 root root     9880 Dec  6 21:47 /usr/lib/libsns_direct_channel_stub.so.1.0.0
lrwxrwxrwx 1 root root       28 Dec  6 21:59 /usr/lib/libsns_fastRPC_util.so -> libsns_fastRPC_util.so.1.0.0
lrwxrwxrwx 1 root root       28 Dec  6 21:59 /usr/lib/libsns_fastRPC_util.so.1 -> libsns_fastRPC_util.so.1.0.0
-rwxr-xr-x 1 root root     9880 Dec  6 21:47 /usr/lib/libsns_fastRPC_util.so.1.0.0
lrwxrwxrwx 1 root root       29 Dec  6 21:59 /usr/lib/libsns_registry_skel.so -> libsns_registry_skel.so.1.0.0
lrwxrwxrwx 1 root root       29 Dec  6 21:59 /usr/lib/libsns_registry_skel.so.1 -> libsns_registry_skel.so.1.0.0
-rwxr-xr-x 1 root root     9952 Dec  6 21:47 /usr/lib/libsns_registry_skel.so.1.0.0
lrwxrwxrwx 1 root root       18 Dec  6 21:59 /usr/lib/libsnsapi.so -> libsnsapi.so.1.0.0
lrwxrwxrwx 1 root root       18 Dec  6 21:59 /usr/lib/libsnsapi.so.1 -> libsnsapi.so.1.0.0
-rw-r--r-- 1 root root 12163280 Sep 28  2021 /usr/lib/libsnsapi.so.1.0.0
lrwxrwxrwx 1 root root       22 Dec  6 21:59 /usr/lib/libsnsdiaglog.so -> libsnsdiaglog.so.1.0.0
lrwxrwxrwx 1 root root       22 Dec  6 21:59 /usr/lib/libsnsdiaglog.so.1 -> libsnsdiaglog.so.1.0.0
-rwxr-xr-x 1 root root    22256 Dec  6 21:47 /usr/lib/libsnsdiaglog.so.1.0.0
lrwxrwxrwx 1 root root       18 Dec  6 21:59 /usr/lib/libsparse.so.0 -> libsparse.so.0.0.0
-rwxr-xr-x 1 root root    30584 Dec  6 21:46 /usr/lib/libsparse.so.0.0.0
lrwxrwxrwx 1 root root       15 Dec  6 21:59 /usr/lib/libssc.so -> libssc.so.1.0.0
lrwxrwxrwx 1 root root       15 Dec  6 21:59 /usr/lib/libssc.so.1 -> libssc.so.1.0.0
-rwxr-xr-x 1 root root    91992 Dec  6 21:47 /usr/lib/libssc.so.1.0.0
-rwxr-xr-x 1 root root     9992 Dec  6 21:46 /usr/lib/libssc_default_listener.so
lrwxrwxrwx 1 root root       15 Dec  6 22:00 /usr/lib/libssd.so -> libssd.so.1.0.0
lrwxrwxrwx 1 root root       15 Dec  6 22:00 /usr/lib/libssd.so.1 -> libssd.so.1.0.0
-rwxr-xr-x 1 root root     9896 Dec  6 21:47 /usr/lib/libssd.so.1.0.0
-rwxr-xr-x 1 root root    46864 Dec  6 21:49 /usr/lib/libstats_calculator_portable.so
lrwxrwxrwx 1 root root       19 Feb 28  2018 /usr/lib/libstonith.so.1 -> libstonith.so.1.0.0
-rw-r--r-- 1 root root    26480 Feb 28  2018 /usr/lib/libstonith.so.1.0.0
-rwxr-xr-x 1 root root    51240 Dec  6 21:47 /usr/lib/libstreamparser.so
lrwxrwxrwx 1 root root       16 Dec  6 21:59 /usr/lib/libsync.so.0 -> libsync.so.0.0.0
-rwxr-xr-x 1 root root     9904 Dec  6 21:46 /usr/lib/libsync.so.0.0.0
-rwxr-xr-x 1 root root    26456 Dec  6 21:46 /usr/lib/libsynx.so
lrwxrwxrwx 1 root root       20 Dec  6 21:59 /usr/lib/libsysutils.so.0 -> libsysutils.so.0.0.0
-rwxr-xr-x 1 root root    34728 Dec  6 21:46 /usr/lib/libsysutils.so.0.0.0
```

```
sh-4.4# ssc_sensor_info
ssc_sensor_info v1.7
sh-4.4#
```

## Reply by Eric Katzfey (ModalAI staff) · 2022-03-31 18:01:07 UTC (in reply to MJ)

@MJ Your library listing looks reasonable. But ssc_sensor_info should dump a bunch of information about all of the sensors it sees so there is definitely something wrong there.

## Reply by MJ · 2022-03-31 18:29:56 UTC (in reply to Eric Katzfey)

@Eric-Katzfey 
Yes...any ideas what to do now? Thanks!

## Reply by Eric Katzfey (ModalAI staff) · 2022-03-31 18:32:43 UTC (in reply to MJ)

@MJ We are discussing internally...

## Reply by Eric Katzfey (ModalAI staff) · 2022-03-31 18:36:19 UTC (in reply to MJ)

@MJ What do you get when you enter ```ps aux | grep ssc``` or ```ps aux | grep sensor```?

## Reply by Eric Katzfey (ModalAI staff) · 2022-03-31 18:52:45 UTC (in reply to MJ)

@MJ Can your reflash the system image? https://docs.modalai.com/Qualcomm-Flight-RB5-system-image/. It will delete everything on your board so backup any important data before doing this. If ```ssc_sensor_info``` doesn't report all of the sensors then px4 will never work as it relies on that ability.

## Reply by MJ · 2022-03-31 20:22:04 UTC (in reply to Eric Katzfey)

@Eric-Katzfey 

```
sh-4.4# ps aux | grep ssc
system    1273  1.0  0.0   2068  1260 ?        Ss   20:16   0:02 /usr/bin/sscrpcd sensorspd
root      3764  0.0  0.0   2708   648 pts/0    S<+  20:20   0:00 grep ssc
sh-4.4#

sh-4.4# ps aux | grep sensor
system    1273  0.9  0.0   2068  1260 ?        Ss   20:16   0:02 /usr/bin/sscrpcd sensorspd
sensors   1281  0.0  0.0 186552  5896 ?        Ssl  20:16   0:00 /usr/bin/sensors.qti
root      4196  0.0  0.0   2708   620 pts/0    S<+  20:21   0:00 grep sensor
sh-4.4#
```

## Reply by MJ · 2022-03-31 20:26:25 UTC (in reply to Eric Katzfey)

@Eric-Katzfey 
Will try to re-flash within a day or two, so I'll get back to you with the updates.

## Reply by MJ · 2022-04-03 22:18:52 UTC

Re-flash solved all the previous issues.

But still I'm unable to arm the unit.

Following instruction provided here
https://docs.modalai.com/Qualcomm-Flight-RB5-user-guide-first-flight/
doesn't help as I receive GPS and AHRS errors (while the unit is placed under open and clear sky).
![68ed5d99-1a09-4798-8b49-bcba121393ed-image.png](https://forum.modalai.com/assets/uploads/files/1649023912383-68ed5d99-1a09-4798-8b49-bcba121393ed-image.png) 
Regarding the GPS, I receive the "GPS accuracy too low" (while receiving 10-12 satellites).
![18064c99-d797-45e3-86d3-720e7288c998-image.png](https://forum.modalai.com/assets/uploads/files/1649024431104-18064c99-d797-45e3-86d3-720e7288c998-image.png) 

![ef1077df-6697-4dc1-87aa-c5753a7b021f-image.png](https://forum.modalai.com/assets/uploads/files/1649024014314-ef1077df-6697-4dc1-87aa-c5753a7b021f-image.png) 

What could be the cause of these errors?
Also is the GPS necessary to at least test the motors? 
Is it possible to fly without the GPS?

## Reply by Guest · 2022-04-05 00:31:06 UTC

Hi @MJ ,

Check to see if you have your outdoor parameters correctly set: https://gitlab.com/voxl-public/flight-core-px4/px4-parameters/-/tree/master/helpers/rb5

Sometimes the ekf2 aid mask is still set to 280. 

You can arm the drone without GPS by setting COM_ARM_WO_GPS to 1.

## Reply by Guest · 2022-04-05 00:33:34 UTC

Also, are the GPS LEDs illuminating? There should be the main one which should go from blue to green when it's ready. And a small one flashing on the side that shows a GPS lock.

## Reply by MJ · 2022-04-05 20:08:39 UTC (in reply to Guest)

@RichieRich 

I have made following changes (WO_GPS to 1 and EFK2_AID_MASK to 1 and to 0)
![3c5c6c98-2bb7-4852-a561-61679657daba-image.png](https://forum.modalai.com/assets/uploads/files/1649191095383-3c5c6c98-2bb7-4852-a561-61679657daba-image.png) 

but now I receive following error:
![6630e46e-496a-4edf-9c39-b8ffc2d2fdeb-image.png](https://forum.modalai.com/assets/uploads/files/1649190918369-6630e46e-496a-4edf-9c39-b8ffc2d2fdeb-image.png) 

The main GPS LED (blue) slowly blinks, but only in blue color.
The FIX LED has short blinks in blue color.

Could you please advise what to do?

## Reply by MJ · 2022-04-06 07:31:13 UTC

Also when I go to QGC - Vehicle setup - Safety, I get this error
![0b7a46dc-eaae-48cf-9587-cca3c59f5fac-image.png](https://forum.modalai.com/assets/uploads/files/1649230173450-0b7a46dc-eaae-48cf-9587-cca3c59f5fac-image.png)

## Reply by MJ · 2022-04-06 07:42:17 UTC

When  EFK2_AID_MASK is set to 1, following errors occur:

![eb9e5812-78b0-4aab-9dd8-256195f54c9d-image.png](https://forum.modalai.com/assets/uploads/files/1649230860273-eb9e5812-78b0-4aab-9dd8-256195f54c9d-image.png) 

I emphasize that drone is under clear and sunny sky
![5d749c53-9845-40f2-a181-09578526d535-image.png](https://forum.modalai.com/assets/uploads/files/1649230929405-5d749c53-9845-40f2-a181-09578526d535-image.png)

## Reply by MJ · 2022-04-07 12:25:50 UTC (in reply to Guest)

@RichieRich 
Are there any updates or suggestions regarding above mentioned issues? Thanks!

## Reply by Guest · 2022-04-07 17:46:02 UTC

EKF2_AID_MASK should be set to 1 for GPS.

Have you set CP_DIST > 0? From the warning, it looks like you have the avoidance system on and it may be seeing something. ![d5e4c765-1797-4451-bee6-abf63c356689-image.png](https://forum.modalai.com/assets/uploads/files/1649353352636-d5e4c765-1797-4451-bee6-abf63c356689-image.png) 

How are you mounting the GPS unit? Just an un-modified RB5 with mast? I assume you're outdoors with a clear view of the sky. In some cases, interference will throw that error. Setting COM_ARM_WO_GPS will always allow you to arm despite GPS errors. If you still can't arm, there's usualy another issue, maybe as stated above that the obstacle avoidance system is enabled. Another place to check is in QGC under safeties to ensure the avoidance system is disabled. 

Againg for the GPS< Flashing blue, means it's still waiting for the GPS to be fully ready. Small blue LED on the side will flash blue showing a lock. 

You can also try opening up the GPS check values or disabling some checks. For instance you can open up ekf2_req_sacc from 0.5 to about 0.75. 
![4f31c84e-bc33-4668-affc-21723162fc03-image.png](https://forum.modalai.com/assets/uploads/files/1648246011949-4f31c84e-bc33-4668-affc-21723162fc03-image.png) 

There's also the GPS check you can experiment with to see what exactly the error is to get to ready (most likely interference). You can try turning off bit 4 for instance. Your mask is currently set to the default 245 or 11110101.
![f7e4a823-9fb9-4d98-ba03-7aa0eb71d6ef-image.png](https://forum.modalai.com/assets/uploads/files/1648246103705-f7e4a823-9fb9-4d98-ba03-7aa0eb71d6ef-image.png) 

![6e6e897e-5915-4891-9861-c0b5a7855682-image.png](https://forum.modalai.com/assets/uploads/files/1648246140226-6e6e897e-5915-4891-9861-c0b5a7855682-image.png)

## Reply by MJ · 2022-04-08 17:14:26 UTC (in reply to Guest)

@RichieRich 
GPS unit is mounted by default (as it comes with RB5 5G drone), mast is locked in vertical postion.
Turning EKF2_REQ_SACC to 0,75 provided no errors from GPS.
Obstacle avoidance was also disabled, so we managed to fly.

But I'm still a bit confused why the obstacle avoidance gives error, since the drone was placed on the ground (concrete pavement), no obstacles within few meters, while the minimum distance was set to only 1 m. But this is current setup that works:
![0de5d598-3401-4512-9e7b-3ef8202ef635-image.png](https://forum.modalai.com/assets/uploads/files/1649438004385-0de5d598-3401-4512-9e7b-3ef8202ef635-image.png) 

Many thanks for your help. We'll try to figure this out and provide info in a few days.