Testing, Verification and Improvements of Timeliness in ROS Processes

This paper addresses the problem improving response times of robots implemented in the Robotic Operating System (ROS) using formal verification of computational-time feasibility. In order to verify the real time behaviour of a robot under uncertain signal processing times, methods of formal verification of timeliness properties are proposed for data flows in a ROS-based control system using Probabilistic Timed Programs (PTPs). To calculate the probability of success under certain time limits, and to demonstrate the strength of our approach, a case study is implemented for a robotic agent in terms of operational times verification using the PRISM model checker, which points to possible enhancements to the operation of the robotic agent

Local abstraction refinement for probabilistic timed programs

We consider models of programs that incorporate probability, dense real-time and data. We present a new abstraction refinement method for computing minimum and maximum reachability probabilities for such models. Our approach uses strictly local refinement steps to reduce both the size of abstractions generated and the complexity of operations needed, in comparison to previous approaches of this kind. We implement the techniques and evaluate them on a selection of large case studies, including some infinite-state probabilistic real-time models, demonstrating improvements over existing tools in several cases

Project Final Report Use and Dissemination of Foreground

This document is the final report on use and dissemination of foreground, part of the CONNECT final report. The document provides the lists of: publications, dissemination activities, and exploitable foregroun

Hybrid verification technique for decision-making of self-driving vehicles

The evolution of driving technology has recently progressed from active safety features and ADAS systems to fully sensor-guided autonomous driving. Bringing such a vehicle to market requires not only simulation and testing but formal verification to account for all possible traffic scenarios. A new verification approach, which combines the use of two well-known model checkers: model checker for multi-agent systems (MCMAS) and probabilistic model checker (PRISM), is presented for this purpose. The overall structure of our autonomous vehicle (AV) system consists of: (1) A perception system of sensors that feeds data into (2) a rational agent (RA) based on a belief–desire–intention (BDI) architecture, which uses a model of the environment and is connected to the RA for verification of decision-making, and (3) a feedback control systems for following a self-planned path. MCMAS is used to check the consistency and stability of the BDI agent logic during design-time. PRISM is used to provide the RA with the probability of success while it decides to take action during run-time operation. This allows the RA to select movements of the highest probability of success from several generated alternatives. This framework has been tested on a new AV software platform built using the robot operating system (ROS) and virtual reality (VR) Gazebo Simulator. It also includes a parking lot scenario to test the feasibility of this approach in a realistic environment. A practical implementation of the AV system was also carried out on the experimental testbed

Agents and Robots for Reliable Engineered Autonomy

This book contains the contributions of the Special Issue entitled "Agents and Robots for Reliable Engineered Autonomy". The Special Issue was based on the successful first edition of the "Workshop on Agents and Robots for reliable Engineered Autonomy" (AREA 2020), co-located with the 24th European Conference on Artificial Intelligence (ECAI 2020). The aim was to bring together researchers from autonomous agents, as well as software engineering and robotics communities, as combining knowledge from these three research areas may lead to innovative approaches that solve complex problems related to the verification and validation of autonomous robotic systems

Model checking security protocols : a multiagent system approach

Security protocols specify the communication required to achieve security objectives, e.g., data-privacy. Such protocols are used in electronic media: e-commerce, e-banking, e-voting, etc. Formal verification is used to discover protocol-design flaws. In this thesis, we use a multiagent systems approach built on temporal-epistemic logic to model and analyse a bounded number of concurrent sessions of authentication and key-establishment protocols executing in a Dolev-Yao environment. We increase the expressiveness of classical, trace-based frameworks by mapping each protocol requirement into a hierarchy of temporal-epistemic formulae. To automate our methodology, we design and implement a tool called PD2IS. From a high-level protocol description, PD2IS produces our protocol model and the temporal-epistemic specifications of the protocol’s goals. This output is verified with the model checker MCMAS. We benchmark our methodology on various protocols drawn from standard repositories. We extend our approach to formalise protocols described by equations of cryptographic primitives. The core of this extension is an indistinguishability relation to accommodate the underlying protocol equations. Based on this relation, we introduce a knowledge modality and an algorithm to model check multiagent systems against it. These techniques are applied to verify e-voting protocols. Furthermore, we develop our methodology towards intrusion-detection techniques. We introduce the concept of detectability, i.e., the ability of protocol participants to detect jointly that the protocol is being attacked. We extend our formalisms and PD2IS to support detectability analysis. We model check several attack-prone protocols against their detectability specifications

Model Checking Security Protocols: A Multiagent System Approach

Security protocols specify the communication required to achieve security objectives, e.g., data-privacy. Such protocols are used in electronic media: e-commerce, e-banking, e-voting, etc. Formal verification is used to discover protocol-design flaws. In this thesis, we use a multiagent systems approach built on temporal-epistemic logic to model and analyse a bounded number of concurrent sessions of authentication and key-establishment protocols executing in a Dolev-Yao environment. We increase the expressiveness of classical, trace-based frameworks by mapping each protocol requirement into a hierarchy of temporal-epistemic formulae. To automate our methodology, we design and implement a tool called PD2IS. From a high-level protocol description, PD2IS produces our protocol model and the temporal-epistemic specifications of the protocol’s goals. This output is verified with the model checker MCMAS. We benchmark our methodology on various protocols drawn from standard repositories. We extend our approach to formalise protocols described by equations of cryptographic primitives. The core of this extension is an indistinguishability relation to accommodate the underlying protocol equations. Based on this relation, we introduce a knowledge modality and an algorithm to model check multiagent systems against it. These techniques are applied to verify e-voting protocols. Furthermore, we develop our methodology towards intrusion-detection techniques. We introduce the concept of detectability, i.e., the ability of protocol participants to detect jointly that the protocol is being attacked. We extend our formalisms and PD2IS to support detectability analysis. We model check several attack-prone protocols against their detectability specifications

A framework for verification of software with time and probabilities

Abstract. Quantitative verification techniques are able to establish system properties such as “the probability of an airbag failing to deploy on demand ” or “the expected time for a network protocol to successfully send a message packet”. In this paper, we describe a framework for quantitative verification of software that exhibits both real-time and probabilistic behaviour. The complexity of real software, combined with the need to capture precise timing information, necessitates the use of abstraction techniques. We outline a quantitative abstraction refinement approach, which can be used to automatically construct and analyse abstractions of probabilistic, real-time programs. As a concrete example of the potential applicability of our framework, we discuss the challenges involved in applying it to the quantitative verification of SystemC, an increasingly popular system-level modelling language.