The hardware of the pneumatic brake device for the HILS is well prepared making use of a commercial product discover more herefrom the target vehicle except for the digital controller. The deceleration and braking forces in Fig eight that were produced by the HILS system are satisfactory in view of the specified braking performance of the focus on teach. There are specific braking behaviors at roughly four seconds, at which time wheel slide happens in the second and fourth wheelsets and the WSP valves start to work. The reason wheel slides ended up observed in only the second and fourth wheelsets is that the necessary adhesion coefficient restrict of the wheel was enhanced at the second and fourth wheelsets simply because the axle load decreased thanks to the weight transfer throughout braking. In this HILS take a look at, we used the variable friction coefficient μd between the disc and the pad alternatively of the continual friction coefficient μd0. The variable friction coefficient among the disc and the pad employed for unexpected emergency braking of the HILS technique is proven as a strong line in Fig 9. This curve implies that the friction coefficient is higher at the preliminary phase of braking owing to the minimal temperature of the brake components, and that it is high at the last stage of braking thanks to the minimal friction pace when compared with the friction coefficient of the intermediate phase of braking. As predicted by Eq , the variable friction coefficient μd was better than the consistent friction coefficient μd0, which was .38 for the present situation. Even even though the experimental outcomes of the dynamometer in Fig 2 are not able to be compared directly with the predicted values in the sound line of Fig 9 since of various abscissa, the reduce of the friction coefficient at the original stage of braking and the boost of the friction coefficient at the ultimate phase of braking in Fig nine show partly the validity of the proposed Eq . Interestingly, if we use the constant friction coefficient μd0 alternatively of the variable friction coefficient μd for the same braking circumstance, as revealed in Fig 8, no wheel slide, even in the second and fourth wheelsets, occurs in the course of the HILS examination. The solid line in Fig 10 demonstrates the tangential brake force on the disc of the fourth wheelset generated by the variable friction coefficient while the dotted line in Fig 10 demonstrates the tangential brake drive generated by the consistent friction coefficient μd0. The greater the brake pressure produced by the variable friction coefficient, the increased adhesion coefficient needed in the wheel-rail make contact with to avoid wheels from sliding. The reached greatest adhesion coefficient between a wheel and rail was considerably less than the needed restrict price for variable μd, and bigger than the essential restrict for continuous μd0, as revealed in Fig eleven. Therefore, wheel slide only occurs for the circumstance with the variable friction coefficient, as shown in the sound line of Fig ten. When wheel slide occurs in a specific wheelset, the brake power of that wheelset decreases to release the wheel slide by opening the WSP valve of that wheelset, as observed in the solid line in Fig 10.