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This paper studies the synthesis of controllers for cyber-physical systems (CPSs) that are required to carry out complex time-sensitive tasks in the presence of an adversary. The time-sensitive task is specified as a formula in the metric interval temporal logic (MITL). CPSs that operate in adversarial environments have typically been abstracted as stochastic games (SGs); however, because traditional SG models do not incorporate a notion of time, they cannot be used in a setting where the objective is time-sensitive. To address this, we introduce durational stochastic games (DSGs). DSGs generalize SGs to incorporate a notion of time and model the adversary’s abilities to tamper with the control input (actuator attack) and manipulate the timing information that is perceived by the CPS (timing attack). We define notions of spatial, temporal, and spatio-temporal robustness to quantify the amounts by which system trajectories under the synthesized policy can be perturbed in space and time without affecting satisfaction of the MITL objective. In the case of an actuator attack, we design computational procedures to synthesize controllers that will satisfy the MITL task along with a guarantee of its robustness. In the presence of a timing attack, we relax the robustness constraint to develop a value iteration-based procedure to compute the CPS policy as a finite-state controller to maximize the probability of satisfying the MITL task. A numerical evaluation of our approach is presented on a signalized traffic network to illustrate our results.
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Toward the Validation of a Novel Measure of Individuals’ Influence During Team Collaborations
Collaborative problem solving (CPS) is an important skill in the modern workforce, and due to its interactive nature, is challenging to assess. The present study builds on work in team sciences to provide initial validation for a metric that quantifies CPS influence—the extent to which each individual contributes toward the team’s CPS processes—using average mutual information (AMI). The measure is investigated in teams collaborating in a computer programming task, where one teammate was assigned to a controller role (i.e., the only person who engaged with the task interface directly). Results suggest the controller had more influence over the team’s CPS processes than the other participants in the triad, providing initial validation for the influence metric. Future work will investigate the measure in classrooms and multiple modalities, and extend the metric in real-time to understand how influence fluctuates over the course of collaboration.
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- Award ID(s):
- 2019805
- PAR ID:
- 10499598
- Publisher / Repository:
- Proceedings of the Human Factors and Ergonomics Society Annual Meeting
- Date Published:
- Journal Name:
- Proceedings of the Human Factors and Ergonomics Society Annual Meeting
- Volume:
- 67
- Issue:
- 1
- ISSN:
- 1071-1813
- Page Range / eLocation ID:
- 290 to 295
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1177/21695067231192643
