fatima_farrukh
Newbie level 2
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Hi every one,
I m using VG440 series Inertial Measurement Unit(IMU). This IMU is 6DOF ,3-axis Accelerometer, 3-axis Gyroscopes and no magnatometer. iI have logged a file by placing it in CG(Central Gravity) point of land vehicle. It gives measurements of accelerometer in "g" ,gyroscope in "radians/sec" and angles in degrees.
I want to estimate velocity from this data. I have taken gravity vector as [0 0 -1]. I calculated rotation matrix from "angle2dcm" function in Matlab and multiplied it with gravity vector. I have named this product as "Gravity_component". Then i have found the true vehicle acceleration by subtracting the "Gravity_comp" from measured accelerometer data. Then I multiplied the result with 9.8 to convert it into m/sec2. Next I have integrated this true acceleration like this:
vel_x(i) = vel_x(i-1) + dt * a_true(i);
Is any step missing in finding velocity? My results are not upto expectation. Velocity amplitude rise to 200 in amplitude that is not true if I consider it m/sec2.
Very Urgent help is required and thanks in anticipation.
I m using VG440 series Inertial Measurement Unit(IMU). This IMU is 6DOF ,3-axis Accelerometer, 3-axis Gyroscopes and no magnatometer. iI have logged a file by placing it in CG(Central Gravity) point of land vehicle. It gives measurements of accelerometer in "g" ,gyroscope in "radians/sec" and angles in degrees.
I want to estimate velocity from this data. I have taken gravity vector as [0 0 -1]. I calculated rotation matrix from "angle2dcm" function in Matlab and multiplied it with gravity vector. I have named this product as "Gravity_component". Then i have found the true vehicle acceleration by subtracting the "Gravity_comp" from measured accelerometer data. Then I multiplied the result with 9.8 to convert it into m/sec2. Next I have integrated this true acceleration like this:
vel_x(i) = vel_x(i-1) + dt * a_true(i);
Is any step missing in finding velocity? My results are not upto expectation. Velocity amplitude rise to 200 in amplitude that is not true if I consider it m/sec2.
Very Urgent help is required and thanks in anticipation.