| 摘要 |
PURPOSE:To discriminate undulations in a friction factor on a road surface, by comparing a value of the braking force coefficient detected with that of another braking force corresponding to the slip ratio detected in a braking force coefficient characteristic to be stored. CONSTITUTION:The value of a slip ratio S is detected at a slip ratio detecting element 42 on the basis of a braking wheel speed V and a pseudo-car speed VR to be secured as an input signal out of an ABS computer 37. On the other hand, the value of a braking force coefficient muB is detected at a braking force coefficient detecting element 43 on the basis of axle load W to be inputted out of an axle load sensor 40 and braking force B to be inputted out of a braking force sensor 41. This slip ratio S and the value of the braking force coefficient muB are inputted into a discriminating part 45, and here, its collation with a road state discriminating map being stored in a memory part 44 is carried out, whereby undulations in a friction factor on a road surface discriminated. At the road state discriminating map, the friction factor of the road surface is set down to a parameter with a graph showing the relation between the slip ratio S of a braking wheel to the road surface and the braking force coefficient muB. |
