An Experimental Safety Analysis using FTA for A Ball Position Control System

Abstract

FTA is a top down, deductive failure analysis method in which an undesired state of a system is analyzed using Boolean logic to combine a series of lower-level events. It is widely used in the aerospace, automotive and other safety-critical intensive systems. This work addresses the use of FTA by using an experiment for safety-critical ball position control system. The work presented here provides a general example illustrating how FTA can be effectively applied to an 8-bit micro-controller (Chip 89S52) based computer control system having little or no hardware protection. The safety analysis reveals several design deficiencies and physical faults for which modifications are needed. This paper also found that, when properly implemented FTA at the right point in the Software Development Life cycle, it makes requirements, design and code reviews more effective. It also identifies single point failures due to software.

Keywords: Safety Critical Systems, Hazards, Safety Integrity Levels

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