In this paper the results of a project funded by Regione Toscana aimed at reducing the power absorption of auxiliary devices in vehicles are presented. In particular the design. testing and application of a magnetorheological clutch (MR) is proposed. aimed at disengaging the vacuum pump. https://www.roneverhart.com/SWW-x-SXSW-Cake-Something-Was-Wrong-2-8x3/