| 摘要 |
PURPOSE:To enable the highly precise detection of a four-wheel slip and four- wheel grip of a four-wheel drive vehicle, by a method wherein the judgement of the four-wheel slip is made when a difference between a wheel acceleration and a vehicle body acceleration is a set value or above while the judgement of the four-wheel grip is made when said difference is below a set value, in the condition other than that of a two-wheel slip. CONSTITUTION:The speeds NF and NR of front and rear wheels are inputted as the average wheel speed V of four wheels to a wheel acceleration calculator 59 and thereby a wheel acceleration GV corresponding to the state of movement of a vehicle body is calculated. The wheel acceleration GV and a vehicle body acceleration G of a vehicle body acceleration sensor 42 are inputted to a four- wheel slip detector 60. An acceleration difference DELTAG between the two accelerations is determined from the relationship of GV>G in the condition other than that of a two-wheel slip, and when this difference is a set value for a slip or above, a four-wheel slip is detected. A four-wheel grip detector 61 makes the judgement of a four-wheel grip when the difference between the wheel acceleration GV and the vehicle body acceleration G turns to be below a set value for a grip in the state of the four-wheel grip. |
