1. -- Suggestions for packages which might be useful: 
  2.  
  3. --  with Ada.Real_Time;         use Ada.Real_Time; 
  4. --  with Vectors_3D;            use Vectors_3D; 
  5.  
  6. package Vehicle_Message_Type is 
  7.  
  8.    -- Replace this record definition by what your vehicles need to communicate. 
  9.  
  10.    type Inter_Vehicle_Messages is null record; 
  11.  
  12. end Vehicle_Message_Type;