An Educational Case Study of Using SysML and TTool for Unmanned Aerial Vehicles Design

The paper shares an experience in using the Systems Modeling Language (SysML) for the design and formal verification of UAVs. In particular, the paper shows how our approach helps detecting early design errors. A UAV in charge of taking pictures serves as educational and running example throughout the paper. The SysML model of the UAV is simulated and formally verified using the free and open-source tool named TTool. This educational case study gives the authors of the paper an opportunity to draw lessons from teaching SysML

Early Detection of Design Errors in the Life Cycle of Unmanned Aerial Vehicles: A SysML Approach

The widespread of Unmanned Aerial Vehicles (UAVs) in various application domains has questioned the design methods used by UAV manufacturers. Migration from document centric approaches to Model-Based ones has stimulated research work on modeling languages and tools that reduce cost development and time to market. Among the various benefits one may expect from using a Model-Based System Engineering approach, the paper essentially considers a model as a reference for early detection of design errors in the life cycle of UAVs. The paper proposes designers to model the UAV in SysML and to use the free software TTool for safety analysis. TTool includes a SysML model editor, a model simulator and formal verification modules that rely safety analysis on mathematics rather than chance. The method associated with SysML and TTool is applied to a UAV in charge of taking pictures

Checking SysML Models against Safety and Security Properties

Systems Engineering, or engineering in general, has long been relying on document-centric approaches. Switching to Model Based Systems Engineering, or MBSE for short, has extensively been discussed over the past three decades. Since about two decades, MBSE has been commonly associated with the modelling language SysML (Systems Modeling Language), that offers a standardized notation, not a methodology of using it. SysML needs therefore to be associated with a methodology supported by tools. In this paper, a methodology supported by the free and open-source software TTool is associated with SysML. This paper focuses discussion on methodological issues, leading the authors to share their experience in real-time systems modeling. Modeling with SysML is more than just drawing the different diagrams. Associated tools offer possibilities to analyze SysML models for specific properties. In this paper, verification addresses both safety and security properties. The TTool model checker inputs the SysML model enriched with safety properties to be verified and outputs a yes-no answer for each property. Security verification checks SysML models against confidentiality, integrity and authenticity properties. As an illustration of the proposed approach, an aircraft cockpit door control system is modeled in SysML and verified against safety and security properties

Early Checking of SysML Models Applied to Protocols

The paper shares an experience in using SysML and the free, open-source software TTool for protocol modelling and communication architecture validation. A dialogue between a pilot and a control tower serves as running example to demonstrate the benefits of complementary model analysis techniques: simulation, model checking, and verification by abstraction. The proposed method may be adapted to other modelling languages and tools

A Time Stamped Virtual WORM System

When backup operators have to handle giga bytes of information daily, they usually find the task hard enough to leave security aside. This paper consequently intends to focus on proving documents' authenticity regarding both content and date. In the context of WORM technology, it proposes a media independent tamper evident system - using original cryptographic hash function techniques - and secure time stamping within a given accuracy. Finally, time stamping upgrade mechanisms are proposed to extend security guarantees over years