Control software model checking using bisimulation functions for nonlinear systems

Abstract — This paper extends a method for integrating source-code model checking with dynamic system analysis to verify properties of controllers for nonlinear dynamic systems. Source-code model checking verifies the correctness of control systems including features that are introduced by the software implementation, such as concurrency and task interleaving. Sets of reachable continuous states are computed using numerical simulation and bisimulation functions. The technique as origi-nally proposed handles stable dynamic systems with affine state equations for which quadratic bisimulation functions can be computed easily. The extension in this paper handles nonlinear systems with polynomial state equations for which bisimulation functions can be computed in some cases using sum-of-squares (SoS) techniques. The paper presents the convex optimizations required to perform control system verification using a source-code model checker, and the method is illustrated for an example of a supervisory control system. I

Autonomous Systems, Robotics, and Computing Systems Capability Roadmap: NRC Dialogue

Contents include the following: Introduction. Process, Mission Drivers, Deliverables, and Interfaces. Autonomy. Crew-Centered and Remote Operations. Integrated Systems Health Management. Autonomous Vehicle Control. Autonomous Process Control. Robotics. Robotics for Solar System Exploration. Robotics for Lunar and Planetary Habitation. Robotics for In-Space Operations. Computing Systems. Conclusion

Formal Synthesis of Controllers for Safety-Critical Autonomous Systems: Developments and Challenges

In recent years, formal methods have been extensively used in the design of autonomous systems. By employing mathematically rigorous techniques, formal methods can provide fully automated reasoning processes with provable safety guarantees for complex dynamic systems with intricate interactions between continuous dynamics and discrete logics. This paper provides a comprehensive review of formal controller synthesis techniques for safety-critical autonomous systems. Specifically, we categorize the formal control synthesis problem based on diverse system models, encompassing deterministic, non-deterministic, and stochastic, and various formal safety-critical specifications involving logic, real-time, and real-valued domains. The review covers fundamental formal control synthesis techniques, including abstraction-based approaches and abstraction-free methods. We explore the integration of data-driven synthesis approaches in formal control synthesis. Furthermore, we review formal techniques tailored for multi-agent systems (MAS), with a specific focus on various approaches to address the scalability challenges in large-scale systems. Finally, we discuss some recent trends and highlight research challenges in this area

Electrical Optimization of a Plug-In Hybrid Electric Vehicle

Hybrid electric vehicles electrification and optimization is a prominent part of today’s automotive industry. GM and the Department of Energy challenge 16 universities across North America to redesign a Chevrolet Camaro into a hybrid electric vehicle. This thesis will address how Embry Riddle Aeronautical University’s EcoCAR team electrified and optimized the vehicle. The objective of the thesis is to optimize the electric portion of the vehicle, particularly the low voltage circuitry. Prior work is discussed in detail on the vehicle communication bus, building the power distribution unit and the approach the electrical team took when building the electric portion of the vehicle. Simulations were done based on manufacturer data and bench tests to create an ideal model. Data was collected from the vehicle and compared to the ideal model to determine errors in the electrical system. An emphasis was placed on critical and high power components to simplify the simulation model. The issues found were alleviated by conducting research, using research analysis, physically changing the system or by implementing control strategies. Most of the issues came from the power distribution unit and implementation techniques such as grounding. The MOSFETs within the power distribution unit was not fully turning on and off, and which was due to a slow RC time constant occurring on the gate of the transistors. By replacing the resistors, this issue was mitigated. Every problem found was properly mitigated to an acceptable industry or research standard

An Organizational Analysis of the Processing Services Division, Thomas Cooper Library, University of South Carolina

This report presents results of an organizational analysis conducted of the Processing Services Division of Thomas Cooper Library at the University of South Carolina. The authors reviewed a selection of the recent literature relevant to technical services. The authors also compiled and analyzed the recent history, organization structure, mission, goals, and objectives for Thomas Cooper Library and the Processing Services Division. The report presents results from twelve interviews with Division staff, management, and Library administration; an exploration of catalog use statistics; and a staff time allocation study. Recommendations were made regarding the organizational structure, incorporating a team approach, physical space considerations, training and development, and use of metrics