Influence of the temperature on the dry-clutch engagement control in gear-shift manoeuvres

Recent evolutions in the developments of automated dry clutches and the associated control algorithms has led to a rapid diffusion of this transmission type. However the chosen control strategy affects strongly the passenger´s comfort and moreover the control action, particularly with regard to the clutch engagement, is influenced by the clutch torque characteristic model implemented in the Transmission Control Unit (TCU). Thus, to use a phenomenological approach to model the torque transmitted by the specific clutch architecture is a crucial issue in order to design robust engagement control strategies. Thus, to use a phenomenological approach to model the torque transmitted by the specific clutch architecture is a crucial step in order to design robust engagement control strategies. For these reasons this paper investigates the engagement performance of an actuated dry clutch by taking into account the thermal effects both on the cushion spring reaction and on the facing materials and consequently on the clutch torque characteristic. The outcome of this analysis could prove valuable for designers of automated clutches and control engineers to overcome the well known poor engagement problem. Index Terms- dry clutch, automated manual transmission, model predictive control, temperature effect.