Raspberry pi 4 multiple sensor with madgwick filter

[zeeblaze]

Am trying to use the madgwick filter in this repo to get multiple (15) MPU9250 all placed on human body for motion sensing...is this a good filter?...and is the library in this repo compatible with raspberry pi?

[kriswiner]

Managing 15 MPU9250 is possible but I would worry about latency if you use the method of toggling the I2C address as here https://github.com/kriswiner/MPU9250/tree/master/Dual_MPU9250. The alternative is to use an I2C or SPI multiplexer...

None of the sketches in this repo are designed for the RspB pi but could be made to work with same with minor modifications.

On Fri, Oct 9, 2020 at 2:12 PM zeeblaze notifications@github.com wrote:

Am trying to use the madgwick filter in this repo to get multiple (15) MPU9250 all placed on human body for motion sensing...is this a good filter?...and is the library in this repo compatible with raspberry pi?

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[zeeblaze]

Yes...am planning to use the TCA9548A i2c multiplexer

[zeeblaze]

The problem is is this library ok for cross platform build? And am planning to use C++

[zeeblaze]

Or if you can give a clue what will be added or removed to be compatible with Raspberry pi 4🙂

[kriswiner]

No idea, maybe ask Simon Levy?

On Fri, Oct 9, 2020 at 3:03 PM zeeblaze notifications@github.com wrote:

Or if you can give a clue what will be added or removed to be compatible with Raspberry pi 4🙂

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[zeeblaze]

If this works on an Arduino...can I make it process the values locally and the Arduino locally and send it to raspberry pi via i2c with multiplexer?

[kriswiner]

Maybe. You can certainly use something like a Ladybug or Teensy to collect the data, and then how you get it to the pi is up to you. I2C/SPI or UART all should work. But I don;t use the pi so really do not know for sure.

On Fri, Oct 9, 2020 at 3:47 PM zeeblaze notifications@github.com wrote:

If this works on an Arduino...can I make it process the values locally and the Arduino locally and send it to raspberry pi via i2c with multiplexer?

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[zeeblaze]

Maybe. You can certainly use something like a Ladybug or Teensy to collect the data, and then how you get it to the pi is up to you. I2C/SPI or UART all should work. But I don;t use the pi so really do not know for sure.

On Fri, Oct 9, 2020 at 3:47 PM zeeblaze notifications@github.com wrote:

If this works on an Arduino...can I make it process the values locally and the Arduino locally and send it to raspberry pi via i2c with multiplexer?

— You are receiving this because you commented. Reply to this email directly, view it on GitHub https://github.com/kriswiner/MPU9250/issues/433#issuecomment-706433180, or unsubscribe https://github.com/notifications/unsubscribe-auth/ABTDLKXKT4VCK3KUIQWMHETSJ6HJTANCNFSM4SKRJUJA .

The Arduino ladybug only supports spi...while the teensy supports i2c...how do I go about the Arduino support i2c?

[kriswiner]

Ladybug https://www.tindie.com/products/tleracorp/ladybug-stm32l432-development-board/ (or Dragonfly https://www.tindie.com/products/tleracorp/dragonfly-stm32l47696-development-board/) supports I2C, UART, SPI, and I2S.

On Fri, Oct 9, 2020 at 4:13 PM zeeblaze notifications@github.com wrote:

Maybe. You can certainly use something like a Ladybug or Teensy to collect the data, and then how you get it to the pi is up to you. I2C/SPI or UART all should work. But I don;t use the pi so really do not know for sure.

On Fri, Oct 9, 2020 at 3:47 PM zeeblaze notifications@github.com wrote:

If this works on an Arduino...can I make it process the values locally and the Arduino locally and send it to raspberry pi via i2c with multiplexer?

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433 (comment)

https://github.com/kriswiner/MPU9250/issues/433#issuecomment-706433180, or unsubscribe

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The Arduino ladybug only supports spi...while the teensy supports i2c...how do I go about the Arduino support i2c?

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[zeeblaze]

I want a cheap one cause I need 15 of them😌...will ATmega328p work?

[kriswiner]

What is it that you are trying to do?

You can read all 15 of the MPUs with a single Dragonfly board using I2C (latency?) or SPI (better, lower latency). Why do you need 15?

On Fri, Oct 9, 2020 at 4:27 PM zeeblaze notifications@github.com wrote:

I want a cheap one cause I need 15 of them😌...will stm328p work?

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[zeeblaze]

What is it that you are trying to do?

You can read all 15 of the MPUs with a single Dragonfly board using I2C (latency?) or SPI (better, lower latency). Why do you need 15?

On Fri, Oct 9, 2020 at 4:27 PM zeeblaze notifications@github.com wrote:

I want a cheap one cause I need 15 of them😌...will stm328p work?

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You mean I can process all 15 individual sensors from the ladybug and send it to the rpi?..cause the individual sensors will take the movement (rotation) of each body part they are connected to control bones of a 3d model.

[kriswiner]

If you want to measure sensor data, then yes a single Dragonfly (Ladybug has too few GPIOs) can read the data from 15 sensor boards and pass it via I2C to an RPi. Lots of considerations including how to calibrate, select each sensor, power usage for portability. This https://www.tindie.com/products/onehorse/chainable-10-dof-motion-sensor/# might be a useful solution.

If you can find a way to adequately calibrate each sensor, running the sensor fusion on the Pi might get you to 4 degree heading accuracy. Pitch and roll should be good to ~1 degree.

If you want absolute orientation at each point, I would use one of these https://www.tindie.com/products/onehorse/ultimate-sensor-fusion-solution-lsm6dsm-lis2md/ or these https://www.tindie.com/products/onehorse/max32660-motion-co-processor/ and simply send yaw, pitch and roll to the on-board SPI flash for storage and upload to a pc, or send along to a Pi for further processing.

This avoids the need to do the fusion on the pi and will get you to ~2 degree heading accuracy with easier calibration in the case of the EM7180 and <1 degree heading accuracy with no calibration in the case of the MAX32660 coprocessor solution..

Low cost is relative. If you want accuracy and ease of use, it will cost a little more. But in any case, you just need the one Dragonfly.

On Fri, Oct 9, 2020 at 11:04 PM zeeblaze notifications@github.com wrote:

What is it that you are trying to do?

You can read all 15 of the MPUs with a single Dragonfly board using I2C (latency?) or SPI (better, lower latency). Why do you need 15?

On Fri, Oct 9, 2020 at 4:27 PM zeeblaze notifications@github.com wrote:

I want a cheap one cause I need 15 of them😌...will stm328p work?

— You are receiving this because you commented. Reply to this email directly, view it on GitHub

433 (comment)

https://github.com/kriswiner/MPU9250/issues/433#issuecomment-706442324, or unsubscribe

https://github.com/notifications/unsubscribe-auth/ABTDLKTITJDRUDFKHP2XAFDSJ6L6TANCNFSM4SKRJUJA .

You mean I can process all 15 individual sensors from the ladybug and send it to the rpi?..cause the individual sensors will take the movement (rotation) of each body part they are connected to control bones of a 3d model.

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[zeeblaze]

Ok... thanks Mr kris