Study on improvement of reliability of ACU internal fault detection logic using the virtual semiconductor signal modeling technique.

摘要

The Air bag Control Unit (ACU) is responsible for detecting the impact and rollover of the vehicle and operating the appropriate restraint system to protect the occupants. ACU internal microprocessor (MCU) diagnoses the problem caused by failure of the ACU internal semiconductor, such as the inertia sensor and ASIC, as internal failures, and utilizes the signal to control the restraint system and the warning lamp. If MCU can not detect abnormal signals or control required, it may lead to serious vehicle defects, such as air bag malfunction/non-operating operation. For this reason, although it is very important to ensure the reliability of fault detection logic, the traditional approach to the assessment was to present problems that could result in human error during the evaluation process along with the input of many human resources and time resources. In order to overcome these problems, this paper proposes new methods of evaluation using semiconductor signal modelling and failure infusions. The advantage of this method is that the failure state of the semiconductor can be controlled up to the bits of data without having to modify the MCU source code so that the computerized verification can be performed. The text describes the process for deriving internal failure items and constructing the environment, and the actual results of verification using them.