For military all-terrain vehicles, there is a need to radically increase tactical and operational mobility through new modalities by fundamentally improving vehicle terrain control. By characterizing the tire relaxation length and time constants for lateral and longitudinal dynamic changes, mobility control can be enhanced to accommodate agile tire dynamics.
This paper analyzes the transient period of the tire reaction force development process, which is characterized by the relaxation length, for the purpose of agile tire dynamics control as a pre-emptive, fast and exact response of a tire to dynamic changes of its interaction with terrain. In this regards, a comprehensive literature review was undertaken and the tire relaxation length was analyzed for different types of vehicles and their operational velocities. The time relaxation constants, which are derived from the relaxation length, are determined and analyzed based on the data gathered in technical literature. Based on the analysis, reference magnitudes of the time relaxation constants are proposed to be used in agile tire dynamics control algorithm and hardware developments of military all-terrain vehicles.