GPS Sensor Question

[evasnphysics]

We finally received our first GPS sensors and are updating our software so we can play around with them a bit, but detailed documentation has been hard to find (beyond the KB articles linked on the product page). Would anyone be able to point us to more detailed information or at least address a question?

We see that in addition to location, the sensors also outputs heading, linear accelerations, and angular velocities. We assume that these values are calculated from the QR strip image data, similar to the location data, and were planning on comparing it to an inertial sensor (or using one as backup if the GPS is lost or contains too much error). However, we are not certain.

Can anyone confirm that this “secondary” data is calculated from the QR strip or does the GPS have it’s own internal inertial sensor, making an outside one redundant.

Note: My team that will be experimenting with his sensor is currently using Simulink and it has to be updated to 2022b for GPS sensor support.

[jpearman]

@evasnphysics

Can anyone confirm that this “secondary” data is calculated from the QR strip or does the GPS have it’s own internal inertial sensor, making an outside one redundant.

The GPS sensor has its own inertial sensor (that is, combination of 3 axis gyro and accelerometer), however, this is used internally to augment the calculations for roll, pitch, heading etc. that we are calculating from the camera/strip data and we generally do not make these available to user code. You can read back raw accelerometer and gyro values, it’s also possible to read the IMU quaternion data back (need to subclass the gps), but you would then need to perform your own transform into angles. So generally, for simplicity, it’s probably better to have an additional IMU.

[turbodog]

Color me shocked… wow.