Hello,
I want to measure the absolut hand movement. With the MPU 6050 acceleration measurement, I have the Issue, that the Gravity is included. Is there a possibility to substract the gravity or use a sensor who calculate the absolut movement.
Any help will be appreciated.
Kind regards
the MPU 6050 gives you acceleration on 3 axis relative to the chip orientation.
does your chip only translate in space or does it rotate too?
A sensor in rest will always report effective acceleration of 1 g. A moving sensor will show a different value, but as long as you don't know the direction towards geocenter you can't tell the direction of the move.
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Hello, the measurement should give me the translation in space with the rotation. I hope I can remove the gravity and sum the acceleration up to an absolut movement.
Hello, I hope it is possible to remove the gravity. Do you know, if there is a sensor for this purpose? If I read the smartphone data, it gives me the acceleration in space without gravity as well.
the MPU-6050 by itself does not have the capability to subtract the acceleration due to gravity from its measurements directly.
When you read data from the accelerometer within the MPU-6050, you will get measurements that include both the acceleration due to gravity (which is a constant force) and any other acceleration the device is experiencing
To separate the gravitational component from the linear acceleration, you will need to perform what is called sensor fusion combining the data from the accelerometer and gyroscope to estimate the device's orientation and linear acceleration without gravity. some libraries do that (see GitHub - ElectronicCats/mpu6050: MPU6050 Arduino Library or may be Adafruit_MPU6050) but sensor's calibration, sensor noise, and the accuracy of your orientation estimation are critical...
If the MPU-6050 is rotating, it introduces additional complexities as its accelerometer will measure both the gravitational acceleration and the centrifugal acceleration due to the rotation which acts as an additional linear acceleration that can be confused with real linear motion.
Accurately estimating the centrifugal acceleration and compensating for it is challenging, especially if the rotation is fast or if there are sudden changes in rotation. I'm not aware of libraries doing this.
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It is possible, but not with a consumer grade IMU, and especially not with the long obsolete, noisy MPU-6050. IMUs accurate enough for that purpose cost in the range of USD 10K - 50K.
For an explanation of the major problem, see this article: Using Accelerometers to Estimate Position and Velocity | CH Robotics
You can’t successfully integrate acceleration to give velocity or position .
Hello Jackson, thank you for your awesome tipp. With an ESP-32 this library works fine for me. I can remove the gravity. Thats enough for my purpose. 
good to hear
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