I'm looking for the best coordinate system projection to use for cartesian calculations while a vehicle is running from its starting location to about 100 miles from that spot.
The offline format for coordinates will be WGS84 geodetic coordinates. For online operation I am looking for the best coordinate system projection to use. We have decided that the best way to go about this is to define a projection with the origin at the vehicle's starting location.
Currently the primary candidates are an orthographic aka standard cartesian coordinate system set tangent to the earth at the starting lat/lon of the robot, or a transverse mercator projection defined at the starting x/y coordinate of the robot. We are avoiding UTM coordinates because we are likely to be on or near UTM boundaries so distortions would be a problem.
I am leaning towards the transverse mercator coordinate system, though I am not 100% confident how to appropriately configure the datums, particularly the scale factor, at arbitrary lat/lon coordinates.
For orthographic it seems that distortion would become a problem as early as the 50 mile mark from the starting location.
Ultimately my question is which coordinate system would be the best choice, and how to I choose parameters such as the scale factor appropriately based on the starting location?