Fault Isolation in the Hydraulic Circuit of an ABS: A Real-World Reference Problem for Diagnosis

We present requirements and success criteria for the realworld problem of (off-board) diagnosis of the hydraulic circuit of an anti-lock braking system. The primary problems to be addressed are quite fundamental: First, it is practically impossible to predict the dynamic behavior of this controlled automotive system as it depends on a number of unknown context conditions. Second, there are no direct measurements of the actual behavior available. Instead, the only available input are a number of temporally unspecified and inherently vague symptoms such as "vehicle is yawing to the right". Both problem dimensions might be considered a real challenge for model-based prediction and consistency checking techniques. A number of diagnostic scenarios for the system have been selected based on existing failure mode and effects analysis (FMEA) documents. Their practical relevance is confirmed by experts in the domain. Description of the Application Domain