Planar air-bearing microgravity simulators: Review of applications, existing solutions and design parameters

In this brief, the nanosatellite rendezvous and docking problem is tackled. It was never attempted for small spacecraft, as critical technologies, such as six-degree-of-freedom (DoF) micropropulsion systems, have only recently become available due to advances in MEMS. The typical level of noise in nanosatellites’ sensors and actuators combined with the dynamics uncertainties, low actuation capabilities, and reliability requirements makes the use of robust control appropriate. The system is described by a linearized rotation/translation, six DoFs, and coupled dynamics, including fuel sloshing. An ${\mathcal {H}_\infty }$ controller is first designed, in which robust stability and performance are assessed using structured singular values. The controller robustness is then improved using ${{\mu }}$ -synthesis. Nonlinear Monte Carlo simulations for both controllers, including realistic sensors and actuators models, are provided allowing a thorough assessment of the complete guidance, navigation and control (GNC). The sought GNC schemes are shown to be robust to the modeled uncertainties and to satisfy the docking requirements.

/pdf/mathcal-h-infty-and-mu-synthesis-for-nanosatellites-1vm92p2fw2.pdf

$\mathcal{H}_{\infty}$ and $\mu$ -Synthesis for Nanosatellites Rendezvous and Docking

This paper presents a model predictive control strategy for the spacecraft rendezvous hovering phases. Using a sequence of impulsive velocity changes, the spacecraft is controlled to reach and rema...

/pdf/stable-model-predictive-strategy-for-rendezvous-hovering-2xpeu9dvk4.pdf

Stable Model Predictive Strategy for Rendezvous Hovering Phases Allowing for Control Saturation

Rendezvous is one of the fundamental phases of on-orbit servicing (OOS) missions. Since it requires high accuracy and safety, modeling is an indispensable part. Therefore, this article puts forward an approach for boosting the exactitude of the final proximity phase of a servicer spacecraft using precise modeling. Unlike other similar works that solely use linear models to design controllers, this paper employs a fully nonlinear model and considers most possible uncertainties and disturbances. In this regard, first a complete nonlinear relative pose (i.e., concurrent position attitude) motion dynamic is developed, which includes (1) the role of the reaction wheels and (2) the major environmental force and torque model. Second, taking the thruster's adverse torque into account, two sliding mode-based control techniques with different nonlinear sliding surfaces are designed. Moreover, the Lyapunov stability criterion is used to handle high nonlinearity effects, control input saturation, actuator misalignment, external disturbance torque/force, measurement error, uncertainties of both inertia parameters, and control inputs. Even the PWPF modulator of the thrusters has been considered to make the outcomes more realistic. Finally, three different scenarios are comprehensively simulated to illustrate the feasibility and efficiency of the designed scheme. The results prove that the proposed closed-form controller is more executable to implement than other existing approaches. 

https://www.nature.com/articles/s41598-023-30687-9.pdf

Coupled position and attitude control of a servicer spacecraft in rendezvous with an orbiting target

Although soft-docking in space has been demonstrated in the past, these missions have required detailed information about the target vehicle for success, and often relied on manual control during the final stages. Autonomous docking, however, shows the potential to greatly reduce operation costs while accomplishing complex scenarios. Unfortunately, unknown dynamics and changing parameters stress current attitude control systems for docking applications such as spacecraft servicing, debris capture, and space robotics operations. Adaptation for example may assist with vehicle control under such conditions, however requires careful validation. Since autonomous soft-docking has limited heritage when there are system uncertainties, risk reduction prior to operation becomes very important for mission success. In this thesis a verification and validation framework was developed for autonomous soft-docking of spacecraft under such uncertainties. The approach combines riskmanagement techniques, simulation, Monte Carlo analysis, diagnostic tools and experimentation in the micro-gravity environment of the International Space Station (ISS) to create a comprehensive risk-reduction strategy. Development methods are described to provide general guidelines for design of future soft-docking missions. Additionally, this thesis explores how such verification and validation methods may be used to assess how an adaptive controller can maintain attitude control authority when a spacecraft joins with an object with limited physical parameter information. The goal is to chart a path for controller validation via future spaceflight experimentation. The risk reduction framework and controller analyses and tests are based on working with the Synchronized Position Hold Engage Reorient Experimental Satellite (SPHERES) facility at MIT and on the ISS. Thesis Supervisor: David W. Miller Title: Professor of Aeronautics and Astronautics

Development of a verification and validation framework for autonomous soft-docking of spacecraft with uncertain dynamic properties

The present work introduces low authority robust control algorithms and their application in a consistent procedure of Rendezvous and Docking or Berthing of Spacecrafts (RVD/B). This consistency implies achieving a maturity level that guarantees successful docking at least 90% of the time. Robust Nonlinear Adaptive Controllers are developed to compensate the friction effects in ground testing. H ∞ controllers are implemented to take into account the uncertainties of the real system in a 6 DOF environment aboard the International Space Station (ISS) using the Synchronized Position Hold Engage Reoriented Experimental Satellites (SPHERES).

Robust control applied towards Rendezvous and Docking

Handle everyday research tasks with reliable, citation-backed results

Your personal Research Agent to handle research tasks with citation-backed results

Popular Tasks used by Researchers

How can I help with your research?

Meet SciSpace

Get more enhanced response by uploading the PDFs you want me to reference.

No relevant PDFs in your library

SciSpace is the AI research assistant for academics. Run systematic literature reviews on 280M+ papers, and write papers with cited sources. Trusted by 1M+ students, PhDs & researchers.

SciSpace | AI for Research

Analyze PDFs

Code & Manuscripts

Funding & Grants

Literature & Patents

Medical & Clinical Data

Systematic Review

Visualize & Present

Web & Data

Build a Google Scholar-like website for your research.

Build a website

Create charts and images for your research

Create a Chart

Write a paper for submission to a journal

Draft a manuscript

Patent Search

Design eye-catching scientific posters in minutes.

Scientific Poster Generation

Systematic Literature Review

One task is running at the moment. Your messages will be shown right after.

Drag and drop or click here to browse

Loved by <highlight>1 million+</highlight> researchers

Extract a list of specific topics and their sources from unstructured text

Topics

Compare and analyze relevant papers that matches with your search

Papers

Get insights from PDFs and bookmarked papers from your library

My library

Recent searches

Try searching for:

Catch AI-generated content in scholarly and non-scholarly content

{ai} Detector

Ai Writer

Get PDF Summaries, highlighted text explanations 

Chat with PDF

Effortlessly create in-text citations and bibliographies in APA and 2,500 other formats

Citation generator

Get explanations, summaries, and answers on academic papers

Ease up your research workflow with {scispace}'s cohort of exciting AI tools

Elevate your academic writing skills and convey your ideas the way you want

Paraphraser

Explore our range of reading and writing tools

Your file is being prepared and should be ready in a few minutes. If it's a large file, it might take a bit longer. You can close this window, and we'll email you the file when it's done.

You have reached a maximum limit of <strong>{limit}</strong> columns in the table. Remove at least <strong>1</strong> column to add or create another one.

A. Fejzic

Author Tools

Chat about Author

Papers

Robust control applied towards Rendezvous and Docking