Industrial-sized hybrid systems are typically not amenable to formal verification techniques. For this reason, a common approach is to formally verify abstractions of (parts of) the original system. However, we need to show that this abstraction conforms to the actual system implementation including its physical dynamics. In particular, verified properties of the abstract system need to transfer to the implementation. To this end, we introduce a formal conformance relation, called reachset conformance, which guarantees transference of safety properties, while being a weaker relation than the existing trace inclusion conformance. Based on this formal relation, we present a conformance testing method which allows us to tune the trade-off between accuracy and computational load. Additionally, we present a test selection algorithm that uses a coverage measure to reduce the number of test cases for conformance testing. We experimentally show the benefits of our novel techniques based on an example from autonomous driving.

Abstract-Mobile robots operating in a shared environment with pedestrians are required to move provably safe to avoid harming pedestrians. Current approaches like safety fields use conservative obstacle models for guaranteeing safety, which leads to degraded performance in populated environments. In this paper, we introduce an online verification approach that uses information about the current pedestrian velocities to compute possible occupancies based on a kinematic model of pedestrian motion. We demonstrate that our method reduces the need for stopping while retaining safety guarantees, and thus goals are reached between 1.4 and 3.5 times faster than the standard ROS navigation stack in the tested scenarios.

Model-based development is an important paradigm for developing cyber-physical systems (CPS). The underlying assumption is that the functional behavior of a model is related to the behavior of a more concretized model or the real system. A formal definition of such a relation is called conformance relation. There are a variety of conformance relations, and the question arises of how to select a conformance relation for the development of CPS. The contribution of this paper is a survey of the definitions and algorithms of conformance relations for CPS. Additionally, the paper compares several conformance relations and provides guidance on which relation to select for specific problems. Finally, we discuss how to select inputs to test conformance. CCS Concepts: • Computing methodologies → Model development and analysis; • Software and its engineering → Formal software verification;

Abstract. Signal Temporal Logic (STL) is a formalism for reasoning about temporal properties of continuous-time traces of hybrid systems. Previous work on this subject mostly focuses on robust satisfaction of an STL formula for a particular trace. In contrast, we present a method solving the problem of formally verifying an STL formula for continuous and hybrid system models, which exhibit uncountably many traces. We consider an abstraction of a model as an evolution of reachable sets. Through leveraging the representation of the abstraction, the continuoustime verification problem is reduced to a discrete-time problem. For the given abstraction, the reduction to discrete-time and our decision procedure are sound and complete for finitely represented reach sequences and sampled time STL formulas. Our method does not rely on a special representation of reachable sets and thus any reachability analysis tool can be used to generate the reachable sets. The benefit of the method is illustrated on an example from the context of automated driving.

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