Sanjay Jayaram, Ph.D.
Associate Professor of Aerospace and Mechanical Engineering; Program Coordinator in Aerospace Engineering
Ph.D. Mechanical Engineering, University of Central Florida
M.S. Mechanical Engineering, University of Central Florida
B.S. Mechanical Engineering, R.V. College of Engineering, Bangalore, India
Jayaram’s research interests include space systems robust fault tolerant control,
nonlinear control, adaptive control, small spacecraft design, high performance spacecraft
components, mechatronics, real-time health monitoring and diagnostic methodology,
dynamic systems and control and space systems.
Actuator and Sensor Fault Tolerant Control System (FTCS)
A fault-tolerant control system is designed to retain some portion of its control integrity in the event of occurrence of a component or subsystem fault. Fault-tolerant control involves automatically detecting and identifying the failed components and then reconfiguring the control law on-line in response to these decisions. A fault-tolerant control system must have the ability to adjust off-nominal behavior, which occurs during sensor, actuator, or other component faults. The fault-tolerant control system consists of three primary parts: a controller, a fault diagnosis scheme, and a control law reconfiguration mechanism. Key challenges that are addressed in this research are:
- Develop non-linear mathematical model to depict the behavior of the actual system
- Develop Lyapunov Direct method based robust measures for actuator fault detection
- A fault tolerant robust controller which is reconfigurable to redundant back-ups
- A fault-tolerant controller that can engage suitably to either fixed or varied structure to perform its fault-tolerant functions.
- Similar theory is developed for sensor fault tolerant framework using a Bank of Extended Kalman Filters. Nano and Pico
Spacecraft Design and Development (Space Systems Research Laboratory)
The vision of the Space Systems Research Laboratory is to develop and maintain a Space Systems Lab that gives students of many disciplines and levels access to space. The mission of this laboratory is to design, fabricate, test, and operate micro-, nano- and pico-satellites, i.e., satellites in the 50 to 1 kg range, using a broad base of students from aerospace and mechanical engineering, electrical and computer engineering, computer science, and other disciplines. The laboratory supports both research and education. The education mission is to develop interdisciplinary mindset designing simple satellites that give undergraduates and graduate students quick access to space, and a challenging space based educational environment; an example of this is the CubeSat program. The Space Systems Research Lab (SSRL) is equipped to pursue research opportunities in the areas of Autonomous Unmanned Vehicles for Space Systems and Planetary Vehicles as well as Mechatronics/Robotics. Research activities in Advanced Control Systems will also be pursued. Integration & Testing: The lab has a class 10000 clean facility with a soft-wall clean room (7 ft. x 7 ft. by 9 ft. height) for satellite integration. The laboratory has recently added a small thermal vacuum chamber and a vibration table for environmental analysis and acceptance testing of small spacecraft and components. A larger vacuum chamber is used for experimental research in spacecraft thrusters and sensors. Analysis & Training: Modern design and analysis software is used for developing and evaluating new space systems. In addition to standard aerospace tools (CAD, simulation, orbit analysis packages), SSRL has hardware testbeds, including the self-contained EyasSat teaching satellite. Satellite Control Station: SSRL has three spacecraft tracking and command systems: an omnidirectional beacon receiving station, a medium-gain OSCAR UHF/VHF Earth station, and a high-gain 3-meter S-Band station. The OSCAR station is located atop Oliver Hall, whereas the other two stations are on the roof of McDonnell-Douglas Hall. These elements are controlled from a central mission operations control room, and are used to control SLU developed space systems. In addition, SSRL is part of an national satellite control network led by Santa Clara University, and thus SSRL participates in a wider range of University and NASA missions.
Applied FTCS: Autonomous Rendezvous and Docking of Spacecrafts
In this applied FTCS work, the concepts include proximity operations between spacecraft by developing improved relative motion models necessary for spacecraft services such as inspection, interception, rendezvous, and docking. The focus of the research is to detect faulty actuators and sensors which are primarily used to perform precise close proximity maneuvers for rendezvous and docking technologies.
Advanced Controls and Mechatronics
This collaborative interdisciplinary research integrates, at a fundamental level, system design, modeling, and control disciplines to obtain improved performance of the dynamic response of engineering systems using feedback. Research topics includes systems integration, dynamic system modeling, feedback control design, and the fundamentals of systems theory as applied to linear and nonlinear dynamic systems, mechatronics, structural control, aerospace, and mechanical engineering disciplines. Systems under this research involves: Unmanned Ground Vehicles Unmanned Air Vehicles Unmanned Underwater Vehicles Spacecraft and Space Systems
Professional Organizations and Associations
He is a member to many professional societies, including AIAA, and the American Society for Engineering Education. He is currently serving as Treasurer for the Aerospace Division of ASEE and also as Committee Chair for AIAA/ASEE Leland Atwood Awards Committee.
Community Work and Service
Sanjay Jayaram joined Saint Louis University in 2005 as an Assistant Professor in the Department of Aerospace & Mechanical Engineering at Parks and became Coordinator of Aerospace Engineering in August 2013. He worked as a research associate at Florida Space Institute for one year from 1998 to 1999. He has peer reviewed journal and conference publications in many sources with a focus on advanced control systems design and spacecraft engineering. Jayaram heads/mentors several student-design spacecraft at Saint Louis University.