System for detecting road roughness for suspension control and automotive suspension control system utilizing thus detected road roughness as control parameter

摘要

An automotive suspension control system employs a lateral acceleration sensor monitoring a lateral acceleration exerted on a vehicular body. The output level of the lateral acceleration sensor is processed to detect frequency of a occurrence of lateral acceleration magnitude greater than a predetermined threshold level within a predetermined period of time or a predetermined distance to travel. Judgement is made that the vehicle is on a rough road when the detected frequency becomes higher than or equal to a predetermined rough road criterion. The suspension control system, according to the present invention, is responsive to the judgement of rough road condition, to order softer suspension characteristics for satisfactorily suppressing vehicular body attitude change by absorbing vibration energy.