IMU Quaternion 2 values are always 0

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guelee239
Posts: 11
Joined: Sun Jan 26, 2020 5:34 am

IMU Quaternion 2 values are always 0

Post by guelee239 »

I am using HW as a hedgehog, and receive the data from the modem via USB. I have attached my setting and the output.
The quaternion data is somehow weird because the second and the forth values are always 0 even when I move it and tilt it. I have tested with another device, and the result is the same.

Could you give me any tips to solve this issue?
Attachments
2020-01-28_23-41-19.png
2020-01-28_23-42-49.png

smoker77
Posts: 327
Joined: Sat Feb 06, 2016 4:03 pm

Re: IMU Quaternion 2 values are always 0

Post by smoker77 »

Hello,

Please try following:
1. Connect mobile beacon instead modem and check IMU fusion streaming, is it correct? (You will need to enable IMU fusion output in interfaces section of mobile beacon's settings).
2. Enable all options in 'IMU via modem' section and try to get data via modem again.
I see on screenshots you have disabled velocity and acceleration output, but these data are updating in terminal. May be some issue is in selection of data for transmission. We will also check on our side.

guelee239
Posts: 11
Joined: Sun Jan 26, 2020 5:34 am

Re: IMU Quaternion 2 values are always 0

Post by guelee239 »

Thanks for the reply. I changed the setting, and it seems that the problem remains.
The attached files are the setting of my mobile beacon.
Output mode: IMU fusion data
IMU fusion location: enabled
IMU fusion quaternion enabled
IMU fusion velocity: enabled
IMU fusion acceleration: enabled

I am not sure why the IMU fusion lines have these data.
- X, Y, Z =0
- q(2), q(4) = 0
- v(2) = -0.001

If you find something from your end, please let me know:)

P.S. Do you think going back to older firmware and Dashboard would help?
Attachments
2020-01-30_21-03-42.png
2020-01-30_21-03-27.png

guelee239
Posts: 11
Joined: Sun Jan 26, 2020 5:34 am

Re: IMU Quaternion 2 values are always 0

Post by guelee239 »

Hey this is what I found from the values printed out. I believe this information can be helpful to solve the issue.

LINE1: IMU fusion: Timestamp: 00163591, X=0.000 Y= 0.000 Z=0.000 q=0.485,0.000,0.084,0.000 v=-1.157,-0.001,4.249 a=0.881,-6.342,-6.397
LINE2: Address: 22, X: 4.843, Y: 0.841, Z: -1.157, Angle: 0.0 at time T: 163441

When seeing the lines above,
LINE1 q(1), q(3), v(1) = (0.485, 0.084, -1.157)
LINE2 X, Y, Z = (4.483, 0.841, -1.157)

q(1) and q(3) are X*0.1, and Y*0.1. v(1) = Z.
This relationship is shown for every line even if I move the sensor. So, I think there is a issue when reading values from the sensor.

Another example is written below.

IMU fusion: Timestamp: 00151153, X=0.000 Y= 0.000 Z=0.000 q=0.476,0.000,0.092,0.000 v=-1.396,-0.001,1.506 a=-5.588,0.531,-8.137
Address: 22, X: 4.759, Y: 0.922, Z: -1.397, Angle: 0.0 at time T: 151003

smoker77
Posts: 327
Joined: Sat Feb 06, 2016 4:03 pm

Re: IMU Quaternion 2 values are always 0

Post by smoker77 »

Hello,

Thank you for detailed feedback, we will check this issue.
I think this issue is not with reading data from IMU sensor, but with transmission data from mobile beacon via modem, because direct reading from mobile beacon doesn't give such result

guelee239
Posts: 11
Joined: Sun Jan 26, 2020 5:34 am

Re: IMU Quaternion 2 values are always 0

Post by guelee239 »

Hi! Have you found something about this? This problem still occurs to me, and I need the qw qx qy qz values :-( sad sad

qw qx qy qz vx vy vz ax ay az
0.079 0.000 0.304 0.000 1.994 0.000 1.774 2.697 6.950 -6.423

This is an example of the data I have. qx qz vy are always 0.

smoker77
Posts: 327
Joined: Sat Feb 06, 2016 4:03 pm

Re: IMU Quaternion 2 values are always 0

Post by smoker77 »

Hello,

What version of software do you use?
As I remember, we have fixed this issue in last software update (V6.210).
If you have updated the software and the issue is not fixed for you, please clarify what kind of system (IA or NIA) and what types of beacons do you use?

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