# Safety Control with Preview Automaton

## TL;DR

This paper introduces a novel safety control method using preview automaton for switched systems with sensors that provide advance warning of mode switches, enhancing safety in autonomous systems.

## Contribution

It proposes the preview automaton framework and an algorithm for safety control synthesis with preview information in switched systems.

## Key findings

- Developed a mathematical model capturing preview information and switching constraints.
- Designed an algorithm to compute the maximal invariant set for safety.
- Validated approach on autonomous driving case studies.

## Abstract

This paper considers the problem of safety controller synthesis for systems equipped with sensor modalities that can provide preview information. We consider switched systems where switching mode is an external signal for which preview information is available. In particular, it is assumed that the sensors can notify the controller about an upcoming mode switch before the switch occurs. We propose preview automaton, a mathematical construct that captures both the preview information and the possible constraints on switching signals. Then, we study safety control synthesis problem with preview information. An algorithm that computes the maximal invariant set in a given mode-dependent safe set is developed. These ideas are demonstrated on two case studies from autonomous driving domain.