Abstract
This report describes examination of the indicating information on the around vehicles of platoon inside and outside also including the inside of the self-vehicles of the platooning system of the truck of the energy ITS project which aims at CO2 reduction and energy saving. This is a part of construct of the human machine interface (HMI) of a platooning system, and it is thought that it is required in order to ensure the confidence and safety of a driving to the inside and outside of a platoon. Here, fundamental examination of the contents of indicating of the state information of platoon vehicles is shown.