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prajwal98

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Posts posted by prajwal98

  1. 
          #ifdef OUTPUT_READABLE_WORLDACCEL
            #ifdef OUTPUT_READABLE_WORLDACCEL
                // display initial world-frame acceleration, adjusted to remove gravity
                // and rotated based on known orientation from quaternion
                mpu.dmpGetQuaternion(&q, fifoBuffer);
                mpu.dmpGetAccel(&aa, fifoBuffer);
                mpu.dmpGetGravity(&gravity, &q);
                mpu.dmpGetLinearAccel(&aaReal, &aa, &gravity);
                mpu.dmpGetLinearAccelInWorld(&aaWorld, &aaReal, &q);
                Serial.print("aworld\t");
                Serial.print(aaWorld.x);
                Serial.print("\t");
                Serial.print(aaWorld.y);
                Serial.print("\t");
                Serial.println(aaWorld.z);
            #endif

    I want to ask that what is the unit of above aaWorld  values ? I understand that  if i need to get the acceleration without gravity  i need to use these values , but the values that we get from these are in m/s^2?  or do i need to do something  acc_in_ms2=(aaWorld.x*9.8)/16384.0 ? or something else.

    my offset are as follows

    
        mpu.setXGyroOffset(220);
        mpu.setYGyroOffset(76);
        mpu.setZGyroOffset(6);
        mpu.setZAccelOffset(1262);

    and my output is as follows without doing any changes in code provided  after 10-15 sec (the sensor is horizontal)

    aworld	0	28	60
    aworld	-1	29	40
    aworld	5	29	33
    aworld	6	24	20
    aworld	2	23	22
    aworld	-4	13	26
    aworld	-6	11	28
    aworld	-10	11	30
    aworld	-15	5	38
    aworld	-7	-1	36
    aworld	7	-4	37
    aworld	7	0	33
    aworld	4	5	29
    aworld	0	2	30
    aworld	-3	-7	35

    seems coreect all the values converging to zeros..

    but when i move the sensor in one direction , i get totally unexpected values..

    aworld	-415	-306	304
    aworld	-505	-277	318
    aworld	-577	-270	399
    aworld	-587	-207	265
    aworld	-572	-166	63
    aworld	-589	-200	-28
    aworld	-631	-258	-7
    aworld	-638	-292	30
    aworld	-637	-334	29
    aworld	-647	-404	-23
    aworld	-640	-483	-75
    aworld	-611	-542	-72
    aworld	-633	-503	-24
    aworld	-723	-344	17
    aworld	-816	-125	36
    aworld	-908	72	1
    aworld	-988	241	-45
    aworld	-1015	378	-68

    I am moving the sesor only to and fro in one direction  but i am getting these values 

    Why so?

    please help if you have any information /knowledge about this...

    I want acceleration mithout gravity affect in m/s^2

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