Research

Current (PSU): Reachability analysis, model predictive control, hierarchical control, thermal management & electrical systems, hybrid systems
Previous (UMN): Optimal control, constrained optimization, hybrid hydraulic-electric systems, and control over discrete operating decisions

Publications

1. J. Siefert, T. Bird, J. Koeln, N. Jain, H. Pangborn, “Successor Sets of Discrete-time Nonlinear Systems Using Hybrid Zonotopes,” American Control Conference, 2023. (accepted) [arXiv]
2. J. Siefert, T. Bird, J. Koeln, N. Jain, H. Pangborn, “Robust Successor and Precursor Sets of Hybrid Systems Using Hybrid Zonotopes,” IEEE Control Systems Letters, 2022. (jointly submitted to IEEE Conference on Decision and Control)
   
3. J. Siefert, D. Leister, J. Koeln, H. Pangborn, "Discrete Reachability Analysis with Bounded Error Sets", IEEE Control Systems Letters, 2022. (jointly submitted to American Control Conference)
   
4. J. Siefert, P. Y. Li, "Optimal Control of the Energy-Saving Hybrid Hydraulic-Electric Architecture (HHEA) for Off-Highway Mobile Machines", IEEE Transactions on Control Systems Technology, 2021.
   
5. A. Khandekar, J. Siefert, P. Y. Li, "Co-Design of a Fully Electric Hybrid Hydraulic-Electric Architecture (FE-HHEA) for Off-Road Mobile Machines", American Controls Conference, 2021.
   
6. J. Siefert, P. Y. Li, "Optimal control and energy saving analysis of common pressure rail architectures: HHEA & STEAM", BATH/ASME Symposium on Fluid Power and Motion Control, 2020.
   
7. J. Siefert, P. Y. Li, "Optimal operation of a hybrid hydraulic-electric architecture for off-road mobile machines over discrete operating conditions", American Controls Conference, 2020.
   
8. P. Y. Li, J. Siefert, "A hybrid hydraulic-electric architecture (HHEA) for high power off-road mobile machines", BATH/ASME 
   Symposium on Fluid Power and Motion Control, 2019.