A Product by Dassault Systems
Systems are becoming more and more complex in modern industry. As a consequence, it is becoming harder to manage all the aspects of safety analysis and to maintain the safety levels required by certification authorities. To meet always increasing safety requirements, design and safety analysis methods are developed in order to fit the complexity of new complex systems.
According the FAA, EASA and CAAC, system-level safety analysis are supported by two standards:
/// ARP4754 which presents recommendations for the development process of Complex Aircraft Systems “Certification Considerations for Highly-Integrated or Complex A/C Systems”
/// ARP4761 which presents the methods (like FMEA, Fault Trees…) for performing safety analysis “Guidelines and Methods for Conducting the Safety Assessment Process on Civil Airborne Systems and Equipment“
Safety Analysis performed in compliance with these guidelines will be delivered to the certification authorities, such as FAA, EASA and CAAC.
ARP4754 and ARP4761 are linked to DO-178, DO254 and ARP5051 as explained in this graph:
The concept of Model-Based Safety, introduced in the new ARP4754A, recommends to generate from Models the safety assessments described and listed in paragraph 1.2. The use of software tools having received international certification is recommended.
Model Based Safety answers the following problems:
/// Disconnection between requirements, system architecture and safety models
/// Costly rework process
/// Costly system modifications
/// Costly configuration management
Model Based Safety provides the following advantages:
/// High level view of full multidiscipline system
/// Communication among systems engineers and disciplines with a “cross discipline abstraction” modeling
/// Integration and harmonization of system definition models detailed by disciplines
/// Visualization of the system as it or as we want it to be
/// System structured in hierarchical levels & sub-systems
/// Reuse of existing component & architectures (Capitalization information improvement)
/// Fast & easy adaptation for new configurations & evolutions
/// Fast & reliable analyses for each configuration / evolution
/// Concurrent Design for large scale projects
SD9 & FT9, software products by Dassault Systemes, falls into this category of Model-Based Safety tools. They are described in paragraph 2.
It is a solution to validate the product safety requirements compliancy early in the design phase. It allows to define a common functional and dysfunctional model for a complex system. From this reference model, it automates dependability studies in order to enhance and/or certify the system.
