SmartMotion® MEMS Motion Sensors

Hi ,

when design the pcb, i place a magnet near the 9250.
the magnet maybe influence the 9250, and what is the specification of distance between the mange and 9250 ?

Hello,

I find many libraries for Python but none seem to make use of the DMP to get the quaternion. The one I found that uses the FIFO only looks at Accel and Gyro values.

So I have ported the C code for the MPU6050 to Python, from v6.12 of the MotionApp code, but I'm running into issues and i have several questions:

1) FIFO structure:
following dmp_read_fifo code in inv_mpu_dmp_motion.c I expect to see:

16 Bytes for Quaternion (4x4)
6 Bytes for Accel (3x2)
6 Bytes for Gyro (3x2)
4 Bytes for Gesture (4)

In documents, it describes "Motion Driver is designed as a solution which can be easily ported to most MCU."
After I study 6.12 and 5.12 documents, I still have no idea how to ported these driver to my MCU, STM32F303.

It just provide MSP430 and STM32F4 example. However, how to ported to other MCU? Does anyone know more detail information?Tanks a lot.

Hi,

We're using the MPU-6500 with the DMP enabled and 3-axis quaternions, gyro only.

Our question is if the quaternion output is temperature compensated or if that is something we need to apply after we read out the quaternions?

Thanks!

Hello.
I use nRF52 and MPU9250.
I want to get angles with DMP.
Now I try get quaternion with the sample code(Embedded MotionDriver 6.12).

There is a function eMPL_send_quat in this program.
It is get the argument(long* quat).
I want to know about order of quaternion parameter and endianness.
I didn't find description about them.

Thanks,

Yukichi

In our application, our MPU9250 will be every close to magnet (for attraction when charging our component) in standby mode, but it works under normal condition. I am wondering if long-term exposure to such strong magnetic field lead to physical damage for magnetometer in MPU9250. Thanks a lot.

Hi,
I think i may have a problem with my MPU9250 accelerometer.
In my understanding of the accelerometer on the acceleration the value increases and on the breaking the value should be negative. And bouth should be the same area.
I'm using the DMP of the eMD 6.12, pretty much like in the example, acceleration via inv_get_sensor_type_linear_acceleration, 30Hz data update. The Sensor is factory calibrated.

I am getting different values from the FIFO than I am from reading the data registers directly. This happens no matter what the sensitivity is set to. My gyro values at 250dps scale, with the sensor sitting still, are around -120 if I read the values from the data registers. They are +1500 to +3000 if I read them through the fifo. Likewise, if I set it to 1000dps, I get around -35 to -90 in the data registers and +200 to +300 in the FIFO. The values I get in the data registers seem to be more reasonable and realistic for bias values.

Hi!

When I read the raw data output of the gyro x-, y-, and z-axis, I see some offset value when the sensor is stationary. There seems to be variation from device to device. So should I calibrate the MPU-6500 gyro somehow?
Is the gyro offset register used for this? How should the calibration process be done, if required?
The datasheet says that the sensor is factory calibrated, does that mean only for the sensitivity (but not the "DC offset")?