MPU6050 vs. BNO055

Other Hardware Sensors
1

Hi all,

I've been tinkering with the MPU6050 for telescope attitude determination for a while now. However, I'm not really satisfied with the accuracy and especially consistency I was able to archieve - even though I could improve it programmatically.
I was wondering if the BNO055 could be more suitable for the task, since it is advertised as beeing able to output absolute orientation.
Of course, it's not really fair to compare a 6 DOF sensor with a 9 DOF sensor but I'm just looking for some reports from people that know / have used both sensors.
Please also note, that I'm really kind of tinkering / experimenting with this. This is not something I want to have completed in a day or two. I understand that I can always slap two rotary encoders with a geartrain onto the telescope mount and archieve sub-minute accuracy. I'm just fascinated by the possibility of putting a MEMS onto a telescope, without having to do much mechanical modifications.

Best regards!

PS: If anyone should be interested in the code: I've done everything except sensor readout with python, that is than interfaced to stellarium. Let me know if you want the code / some help with setting it up.

PPS: I'm aware of this paper, but it is a bit outdated: [1407.0035] Accurate Telescope Mount Positioning with MEMS Accelerometers

2

Correct, you cannot compare 6DOF and 9DOF sensors. The MPU-6050 is obsolete.

The BNO055 is convenient, but not very accurate. It uses a proprietary but very poor algorithm to calibrate the sensors, and frequently loses calibration.

You can do much better with modern 9DOF sensors (Pololu has a good collection), and the Madgwick or Mahony fusion filter code, but you MUST take the time to carefully calibrate the individual sensors.

See GitHub - jremington/AltIMU-AHRS: Arduino Madgwick/Mahoney AHRS filters for the Pololu AltIMU9 and 10 series of 9 and 10DOF sensors. Includes code for sensor calibration.