Vehicle type categories.

VEHICLE_TYPE_CATEGORY_LOG_UNSPECIFIED Default, used for unspecified or unrecognized vehicle types.
AUTO An automobile.
TAXI Any vehicle that acts as a taxi (typically licensed or regulated).
TRUCK Generally, a vehicle with a large storage capacity.
TWO_WHEELER A motorcycle, moped, or other two-wheeled vehicle.
BICYCLE Human-powered transport.
PEDESTRIAN A human transporter, typically walking or running, traveling along pedestrian pathways.