When making an inertial measurement unit (IMU) especially one used for orientation calculations, the quality of the gyroscope has a big impact on the jitter/speed/drift. Accelerometers are pretty good quality these days, we've figured out how to make them decades ago. And magnetometers are not as important - they don't update often and are used for orientation correction. Gyro's have the most error possibilities.
We compare two basic measurements - the zero offset and the zero noise. Zero offset is easy to correct for, and you should calibrate your gyroscope once its mounted in the final project/PCB - simply take a lot of measurements, find the offset that would bring the gyro to zero. The noise that you get when not moving can be minimized with low pass filtering (sometimes handled in-chip).
Uncalibrated offsets are low, the one we grabbed had 0.006 rad/s (0.35 deg/s) max offset. Datasheet's Angular rate zero-rate level is typical ±1 deg/s.
No-motion observed noise was an incredibly low ±0.002 rad/s (±0.06 deg/sec) when running at 104 Hz and no filters on. Check the datasheet for more details!
LSM6DSOX
This is an high quality 6-DoF IMU with great performance - at an expected higher price than the LSM6DS33. This is the 'commercial usage' version of the ISM330DHC
Uncalibrated offsets are low, the one we grabbed had 0.007 rad/s (0.42 deg/s) max offset. Datasheet's Angular rate zero-rate level is typical ±1 deg/s.
No-motion observed noise was an incredibly low ±0.003 rad/s (±0.17 deg/sec) when running at 104 Hz and no filters on. Check the datasheet for more details!
LSM6DS33
This basic 6-DoF IMU is inexpensive and works well for basic projects. We have it both in 6-DoF and paried with a magnetometer for 9-DoF,
Uncalibrated offsets are fair, the one we grabbed had 0.034 rad/s (2 deg/s) max offset. Datasheet's Angular rate zero-rate level is typical ±10 deg/s!
No-motion observed noise was ±0.015 rad/s (±0.85 deg/sec) when running at 104 Hz and no filters on. Check the datasheet for more details!
The ST LSM6DS3TR-C is a great entry-level 6-DoF IMU accelerometer + gyro and is very similar to the now-discontinued LSM6DS33. We have it both in 6-DoF and paired with a magnetometer for 9-DoF
The one used here had 0.03 rad/s (1.7 deg/s) max offset. Datasheet's Angular rate zero-rate level is typical ±3 deg/s.
No-motion observed noise was ±0.0015 rad/s (±0.085 deg/sec) when running at 104 Hz and no filters on. Check the datasheet for more details!
LSM9DS1
This popular sensor is a 9-DoF all-in-one with a LIS3MDL for the magnetometer, and a 'LSM6DS-like-but-not-the-same-register-map-at-all' accelerometer/gyro IMU
Uncalibrated offsets are pretty good, the one we grabbed had 0.02 rad/s (1.2 deg/s) max offset. Datasheet's Angular rate zero-rate level is typical ±30 deg/s!
However, we noticed spikes of gyro data well outside the expected range. When those spikes are ignore, the no-motion observed noise was +- 0.007 rad/s (±0.4 deg/sec) at 1 KHz with the 408 Hz bandwidth filter on. Check the datasheet for more details!
MPU-6050
This is a fairly old sensor, but very popular and low cost! The quality of the sensor is pretty good considering how old/low cost it is
Uncalibrated offsets are fair, the one we grabbed had 0.04 rad/s (2.3 deg/s) max offset. Datasheet's Angular rate zero-rate level is typical ±20 deg/s!
No-motion observed noise was +- 0.05 rad/s (±0.29 deg/sec) with the 260 Hz bandwidth filter on. Check the datasheet for more details!
NXP FXAS21002
This 3-axis gyroscope sensor is no longer available but we use it in our NXP 9-DoF (and will continue selling it until we can't get the chip anymore) At the time of release it was pretty good, since then better gyros have come out, but it's still not too bad
Uncalibrated offsets are pretty good - the one we grabbed had 0.01 rad/s (0.57 deg/s) max offset. Datasheet's Angular rate zero-rate level is typical post-mount ±50 LSB (NOT deg/s) - at 250 deg/s rate, that translates to ±0.4 deg/s
No-motion observed noise was +- 0.01 rad/s (±0.55 deg/sec) at 100 Hz output. Check the datasheet for more details!
Uncalibrated offsets are not bad, the one we grabbed had 0.023 rad/s (1.3 deg/s) max offset. Datasheet's Angular rate zero-rate level is typical ±5 deg/s
No-motion observed noise was +- 0.015 rad/s (±0.86 deg/sec) at 1.1KHz. Check the datasheet for more details!
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