Time-dependent trajectory information of the vehicle in the state-topic

[umlauditz]

This issue aims to add information about where the vehicle will be at future points in time, to the state-topic.
With such information, features like cooperative-navigation of multiple vehicles is easier.

Our approach would be to either create an additional, optional entry in the state-topic or to extend the "velocity"-state.
The data would look as follows:
An array of {v, omega, deltaT} for several points in time.

• v is the velocity
• omega(w) is the angular speed
• deltaT is the time in seconds for every entry where deltaT=0 is the current time.

With this data every straight or curved trajectory can be calculated.