Skip to Main content Skip to Navigation
Theses

Safety-Bag pour les systèmes complexes

Abstract : Autonomous automotive vehicles are critical systems. Indeed, following their failures, they can cause catastrophic damage to the human and the environment in which they operate. The control of autonomous vehicles is a complex function, with many potential failure modes. In the case of experimental platforms that have not followed either the development methods or the certification cycle required for industrial systems, the probabilities of failure are much greater. Indeed, these experimental vehicles face two problems that impede their dependability, which is the justified confidence that can be had in their correct behavior. First, they are used in open environment, with a very wide execution context. This makes their validation very complex, since many hours of testing would be necessary, with no guarantee that all faults in the system are detected and corrected. In addition, their behavior is often very difficult to predict or model. This may be due to the use of artificial intelligence software to solve complex problems such as navigation or perception, but also to the multiplicity of systems or components interacting and complicating the behavior of the final system, for example by generating behaviors emerging. A technique to increase the safety of these autonomous systems is the establishment of an Independent Safety Component, called "Safety-Bag". This system is integrated between the control application and the actuators of the vehicle, which allows it to check online a set of safety necessities, which are necessary properties to ensure the safety of the system. Each safety necessity is composed of a safety trigger condition and a safety intervention applied when the safety trigger condition is violated. This intervention consists of either a safety inhibition that prevents the system from moving to a risk state, or a safety action to return the autonomous vehicle to a safe state. The definition of safety necessities must follow a rigorous method to be systematic. To do this, we carried out in our work a study of dependability based on two fault prevention methods: FMEA and HazOp-UML, that respectively focus on the internal hardware and software components of the system and on the road environment and driving process. The result of these risk analyzes is a set of safety requirements. Some of these safety requirements can be translated into safety necessities, implementable and verifiable by the Safety-Bag. Others cannot be implemented in the Safety-Bag. The latter must remain simple so that it is easy to be validated. Then, we carried out experiments based on the faults injection in order to validate some safety necessities and to evaluate the Safety-Bag's behavior. These experiments were done on our robotic vehicle type Fluence in our laboratory in two different settings, on the actual track SEVILLE at first and then on the virtual track simulated by the Scanner Studio software on the VILAD testbed. The Safety-Bag remains a promising but partial solution for autonomous industrial vehicles. On the other hand, it meets the essential needs for the safety of experimental autonomous vehicles.
Complete list of metadatas

Cited literature [84 references]  Display  Hide  Download

https://tel.archives-ouvertes.fr/tel-02080272
Contributor : Abes Star :  Contact
Submitted on : Wednesday, March 27, 2019 - 11:34:34 AM
Last modification on : Friday, October 23, 2020 - 4:40:56 PM
Long-term archiving on: : Friday, June 28, 2019 - 1:53:14 PM

File

These_UTC_Manel_Brini.pdf
Version validated by the jury (STAR)

Identifiers

  • HAL Id : tel-02080272, version 2

Collections

Citation

Manel Brini. Safety-Bag pour les systèmes complexes. Autre [cs.OH]. Université de Technologie de Compiègne, 2018. Français. ⟨NNT : 2018COMP2444⟩. ⟨tel-02080272v2⟩

Share

Metrics

Record views

1348

Files downloads

205