Does the magni motors have encoders?

So I am considering using a GPS module for navigating the magni, however, from what I understand is the accuracy of the GPS modules which are provided are not very accurate. Thus I need to introduce some correction factors to the process.

I am using OpenCV for lane detection, for the magni to stay on the specified path, and using GPS for guiding the system through the waypoints. However, I was wondering if encoders were present, so I would monitor the wheel movement and ensure it does not stray off the path.

I was also considering using a magnetometer along with the GPS module, but that would be too many peripherals…


Yes we have wheel encoders. The position of the robot using the wheel encoders alone is published to /odom by default. We check this for each release by the way.

Wheel encoder position is ok for short term resolution of base_link orientation (robot pose) so it is advised to use both GPS and /odom combined using either a kalman filter or other less involved approach.

As far as Magnetometer, the results of a great many robot makers is that magnetometer is greatly effected by local and nearby metals ‘warping’ the B field of or very small signal we get for Earth magnetics. Many people experiment with placing the magnetometer on a post about at least a foot above the robot and so on but if you drive near an iron car or fence be aware that that warps the B field of the earth in often significant ways.

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