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Adaptive Control for Spacecraft with Flexible Appendages with Unknown Parameters
No full textFlexible spacecraft pose several challenges in control design due to the uncertain dynamical model and the underactuated nature of these systems. Adaptive and robust controllers are the common choice for these systems to either meet operational requirements like attitude pointing or to suppress vibrations. However, these controllers add complexity in the design of onboard Attitude Determination and Control Systems (ADCS) and the Reaction Control Systems (RCS) for spacecraft maneuvering. The objective of this research is to control a system that undergoes unpredictable and unknown disturbances through onboard derivation of an equivalent reduced order model designed around mounted sensors. The proposed approach involves designing a self-tuning adaptive attitude controller for unknown flexible spacecraft by identifying a high-fidelity model through numerical and experimental simulations. The models that will be compared are obtained with a lumped-mass system of unknown parameters and an interpolated model using the Theory of Functional Connections (TFC). The unknown parameters of the system are estimated with Integral Concurrent Learning (ICL) and a detailed framework for implementing this architecture onboard using real hardware is presented and validated with experimental results obtained from a real testbed. The outcome of this investigation will create opportunities to implement deployable and morphing devices on smaller spacecraft for capturing large space debris, performing propellantless deorbiting, and autonomous tethered multi-robot systems. This approach allows satellites with flexible solar arrays to maintain precise attitude without complex pre-launch modeling. The extension of the proposed ICL-based adaptive control to a post-capture scenario is presented, showing asymptotic tracking of a desired attitude trajectory for a flexible spacecraft with unknown parameters
Numerical Study on Flow Separation and Performance Characteristics of Slot Nozzle
No full textThe altitude compensating nozzle (ACN) is a type of rocket nozzle or engine that tries to minimize the negative effects of overexpansion at low altitudes. There are many forms of ACN\u27s but most of them are heavier than traditional bell nozzles, alter the geometry of the nozzle, which requires extensive research into optimizing the new geometry, or require complex systems that can lead to structural, heating, or material problems. Out of the ACN\u27s, the slot nozzle is a passive ACN that builds upon the bell nozzle and requires no additional weight or complex systems.
This slot nozzle is comprised of a bell nozzle with an annular slot taken out of the nozzle. This slot allows atmospheric air to flow into the nozzle at low altitudes. While this is physically impossible to manufacture, CFD analysis can be conducted to understand how a passive air-breathing engine operates under different conditions. The slot nozzle is a precursor to designing a permeable nozzle. Modeling or manufacturing a permeable nozzle is complex, so a slot nozzle is modeled to understand the common trends between the passive air-breathing engines.
This study focuses on how flight speed affects the nozzle’s performance and flow patterns at altitudes between 0-30 km. Results indicate that adding flight speed to the slot nozzle allows the slot nozzle to perform better than the traditional bell nozzles at altitudes ≥ 15km. The thrust can increase up to 5.3%. A small increase in flight speed can also increase performance by up to 0.4%. After 30km, the slot nozzle has diminishing performance benefits over the bell nozzle. Increasing the Mach number directly correlates to an increase in thrust performance. The slot nozzle also alters the flow pattern of the nozzle. The slot nozzle proves to be a promising method to understand passive air-breathing engines by showing performance gains and losses compared to a bell nozzl
Panel #5: Space Cybersecurity
No full textPanel #5: Space Cybersecurity
Examines cybersecurity challenges in space systems, including satellite security, communication network threats, and strategies for securing commercial and government space operations.
Moderator: Ron Madler (ERAU)
Panelists:
• Jerry Davis (Microsoft) • Drew Hamilton (TAMU) • Alefiya Hussain (USC ISI) • Derek Schatz (Virgin Galactic) • Matt Tomarchio (Deloitte
Panel #4: Cyber Intelligence and Incident Response
No full textPanel #4: Cyber Intelligence and Incident Response
Explores cyber threat intelligence, risk forecasting, and threat actor analysis, highlighting how AI, data analytics, and collaboration improve threat detection and mitigation.
Moderator: Jon Haass (ERAU)
Panelists:
• Levi Gundert (Recorded Future) • Riley Montgomery (FBI) • Stephen Thomas (NIRT
Aviation Cyber CTF
No full textAviation Cyber CTF
(University teams will compete. Industry attendees encouraged to serve as mentors or participate in the CTF as a learning exercise
Award Presentations (CTF and Poster) in Lower Hangar
No full textAward Presentations (CTF and Poster) in Lower Hanga
Workshop Adjourned
No full textWorkshop Adjourned
(Optional: Guided tour of Prescott Flight Line available hosted by Prof. Parker Northrup
GLIDR - Guided Landing Instrument for Descent and Recovery Capstone
Get PDFThe Guided Landing Instrument for Descent and Recovery (G LIDR) system designed to address the challenges of recovering data from high-altitude Su per Pressure Balloons. The project has outlined the limitations of conventional data col lection methods-specifically, the uncontrol led descent and recovery of data payloads-and establishes the need for a more reliable, safe, and cost-effective solution. Three design concepts are investigated: the Ballistic Paraglider, the Folding Rogallo Wing, and the Lifting Body. Each concept was rigorously analyzed against stringent safety, structural, and performance requirements established by NASA, NIA, and academic standards. Aerodynamic simulations and structural analyses have been employed to evaluate critical para meters such as range, descent time, stability, and shock. Among the alternatives, the Ballistic Paraglider concept emerges as the optimal design due to its inherent stability, superior range performance, and increased manufacturability. By the end of the calendar yea r GLIDR plans to design, build, and test the full-scale system from the specified drop altitude