Research Highlights
My research interests include nonlinear dynamics and control, safety-critical control, and time delay systems with applications to connected automated vehicles, robotic systems, and autonomous systems.
Safety-Critical Control for Robotic Systems

In collaboration with Miso Robotics, we depeloped a safety-critical control algorithm that allows collision-free cooking with robotic manipulators by minimally modifying existing motion plans.

[J19] Singletary et al., Safety-Critical Manipulation for Collision-Free Food Preparation, RAL/IROS 2022

We established a framework for safety-critical control of robotic systems based on reduced-order kinematics. In case of trivial kinematic equations, this leads to model-free control. We implemented the method on legged, wheeled and flying robots to execute obstacle avoidance tasks.

[J17] Molnar et al., Model-Free Safety-Critical Control for Robotic Systems, RAL/ICRA 2022

We used preference-based learning to tune robust safety-critical controllers for performant and provably safe behavior. We implemented this method on a quadruped that is controlled by using on-board cameras, with robustness to disturbances and perception errors.

[P26] Cosner et al., Safety-Aware Preference-Based Learning for Safety-Critical Control, L4DC 2022

We used self-supervised learning to estimate the uncertainty of perception modules, such as stereo vision, and used this uncertainty estimate for robust safety-critical control.

[P24] Cosner et al., Self-Supervised Online Learning for Safety-Critical Control using Stereo Vision, ICRA 2022

We developed a control method to safely transition between various motion primitives (such as lie, stand, walk or jump behaviors) on legged robots. We implemented this approach on a quadruped.

[P23] Ubellacker et al., Verifying Safe Transitions between Dynamic Motion Primitives on Legged Robots, IROS 2021

We established safety-critical controllers that are robust to perception errors, and we implemented them to execute obstacle avoidance tasks by a Segway using on-board cameras.

[P22] Cosner et al., Measurement-Robust Control Barrier Functions: Certainty in Safety with Uncertainty in State, IROS 2021
Safety of Time Delay Systems

We developed a control framework to achieve formal guarantees of safe behavior for control systems that have time delays in their control loops. The frameworks covers systems with input delays and state delays.

[J26] Kiss et al., Control barrier functionals: Safety-critical control for time delay systems, IJRNC 2023
[J23] Molnar et al., Safety-Critical Control with Input Delay in Dynamic Environment, TCST 2023
[P27] Molnar et al., Input-to-State Safety with Input Delay in Longitudinal Vehicle Control, TDS 2022
[P18] Kiss et al., Certifying Safety for Nonlinear Time Delay Systems via Safety Functionals: A Discretization Based Approach, ACC 2021
Motion Planning for Robotic Systems

In collaboration with Dow Chemical, we designed motion plans for quadrupedal robots that allow them to operate in chemical facilities, such as climb up and down in distillation columns.

[J22] Molnar et al., Mechanical Design, Planning, and Control for Legged Robots in Distillation Columns, JCND 2023
Traffic Prediction for Connected Vehicles

In collaboration with Ford, we depeloped an on-board traffic prediction method that provides speed previews for vehicles via vehicle-to-vehicle (V2V) connectivity. Prediction was implemented on a physical vehicle and tested in real highway traffic.

[J15] Molnár et al., Delayed Lagrangian Continuum Models for On-Board Traffic Prediction, TRC 2021
[P25] Molnár et al., On-Board Traffic Prediction for Connected Vehicles: Implementation and Experiments on Highways, ACC 2022
Control of Epidemiological Models

We established controllers for epidemiological models that describe the spread of Covid-19. These controllers give guidance on the required human intervention for mitigating the spread of the virus and for providing safety with respect to the level of infection or hospitalization. Click on the image for a press release of our work.

[J14] Molnár et al., Safety-Critical Control of Compartmental Epidemiological Models With Measurement Delays, IEEE LCSS 2021
[J13] Ames et al., Safety-Critical Control of Active Interventions for COVID-19 Mitigation, IEEE Access 2020