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Direction Problem

susovanpatra00 opened this issue · comments

commented

I have Acceleration data and Gyroscope data with 100Hz. When I am trying to use this, the direction showing is total opposite than the actual direction. Like If I am going in North Direction then it is showing I am going into South Direction. Why is that so??
And what are the parameters I should vary to make it compatible with my sensor(MPU6050 GY-521) ??

commented

An accelerometer and gyroscope alone cannot provide a measurement of magnetic heading. The direction of heading will instead be arbitrary.

commented

Okk,,,so is there any way to find the appropriate direction also?? If I add magnetometer data in this code will it work then??
If you have something else in mind which might help me please tell me

commented

The inclusion of a magnetometer will allow allow measurements of heading to be relative to magnetic north.

commented

ok,,,but there is a case where when is_moving[index] value let's say 4 and for that I get a direction,,,but when I change that value let's say 4.5 the direction is getting totally opposite(180 degree)...why is that??

commented

is_moving is a list of Booleans. Elements can only have values of True or False. A value of 4 or 4.5 does not make sense.

commented

I am sorry that I couldn't make it clear my point. Actually I was talking about this line -

    is_moving[index] = numpy.sqrt(acceleration[index].dot(acceleration[index])) > 4.5 # threshold = 3 m/s/s

I need one more help. Let's say I have magnetometer data then what changes do I need to do in the below section ??
As here it is using a function named 'ahrs.update_no_magnetometer'. So what changes do I need to do ?

delta_time = numpy.diff(timestamp, prepend=timestamp[0])

euler = numpy.empty((len(timestamp), 3))
internal_states = numpy.empty((len(timestamp), 3))
acceleration = numpy.empty((len(timestamp), 3))

for index in range(len(timestamp)):
    gyroscope[index] = offset.update(gyroscope[index])

    ahrs.update_no_magnetometer(gyroscope[index], accelerometer[index], delta_time[index])
    
    euler[index] = ahrs.quaternion.to_euler()

    ahrs_internal_states = ahrs.internal_states
    internal_states[index] = numpy.array([ahrs_internal_states.acceleration_error,
                                          ahrs_internal_states.accelerometer_ignored,
                                          ahrs_internal_states.acceleration_recovery_trigger])

    acceleration[index] = 9.81 * ahrs.earth_acceleration  # convert g to m/s/s

Please Help !!

commented

You would replace ahrs.update_no_magnetometer with ahrs.update as per the examples and documentation in Fusion.