Question about the Primehub.imu.heading() and Primehub.imu.reset_heading()

[Digital-Dominators]

Hi,
We are new to Pybricks (Our FLL team used SpikePrime block coding last season and this is our 2nd season).

I was testing the imu.heading() and imu.reset_heading() method, and I did the following:

hub = PrimeHub()
left_motor=Motor(Port.C, Direction.COUNTERCLOCKWISE)
right_motor=Motor(Port.B)

drive_base=DriveBase(left_motor, right_motor, wheel_diameter=56,axle_track=112)
drive_base.use_gyro(True)

print(f'Before test: heading is {hub.imu.heading()}')

print('1st turn 60 degrees--------------')
drive_base.turn(60)
print(f'After 1st turn: heading is {hub.imu.heading()}')

print('Reset heading -------------------')
hub.imu.reset_heading(0)
print(f'After reset: heading is {hub.imu.heading()}')

print('2nd turn 60 degrees--------------')
drive_base.turn(60)
print(f'After 2nd turn: heading is {hub.imu.heading()}')

I made 2 60-degree turns and reset the heading in the middle. The imu.heading() was reset to 0 before the 2nd turn. But after the 2nd 60 dgree turn, it became 120 (which I expect to be 60). I wonder if it is a bug (which isn't likely as it is a very common method), or it is me who misunderstood these 2 functions imu.heading() and imu.reset_heading().

Could someone help me here and let me know how to code the 2nd turn to get the heading() reading to 60 after the turn?

This is the print out

Before test: heading is 0.0
1st turn 60 degrees--------------
After 1st turn: heading is 65.1416
Reset heading -------------------
After reset: heading is 0.0
2nd turn 60 degrees--------------
After 2nd turn: heading is 118.3906

(Also I noticed, the robot turned and accelerated much faster in the 2nd turn, though I didn't change any turn_rate or acceleration parameters in the middle),

[laurensvalk]

Thanks for reporting! We will look into it.

[laurensvalk]

Sorry for the delay on this. The issue is the following:

drive_base.turn(60) # After this, the robot is actively holding the 60-degree position.

hub.imu.reset_heading(0) # But this tells the current position to be zero, so the 60 degree position is 60 degrees away again!

# It was still trying to hold 60-degrees, so it is going to rapidly try to self-correct, thus appearing to suddenly accelerate quickly.

We are currently revising and improving these methods. So my question for you is:

• What would you like to do?
• What did you expect to happen?

This will help us add the right functionality, as well as better document the existing functions like these. Thank you!