Results 51 to 60 of about 4,185,262 (226)

An Open Database of Lunar Regolith and Simulants Properties

International Journal for Numerical and Analytical Methods in Geomechanics, EarlyView.
ABSTRACT Lunar regolith, the layer of unconsolidated material covering the Moon's surface, is central to the science and technology developed for the Moon, notably related to in‐situ science investigations, resource utilization, surface infrastructure, and mobility systems.
Léonie Gasteiner, Naomi Murdoch, Olfa D'Angelo   +2 more
wiley   +1 more source

Sliding Mode Control in Aerospace Applications: A Survey

International Journal of Robust and Nonlinear Control, EarlyView.
ABSTRACT Sliding mode control (SMC) enjoys robustness to matched and unmatched (in the case of minimum phase input‐output dynamics) bounded perturbations, and finite time convergence. Second‐order and higher‐order sliding mode control systems (2‐SMC/HOSMC) retain all the advantages of sliding mode control, but in addition can be applied to systems of ...
Yuri Shtessel, Christopher Edwards
wiley   +1 more source

Stair‐Climbing Wheelchairs for Enhanced Mobility: A Comprehensive Review of Fundamental Mechanisms, Design Concepts, and Performance Analysis

Journal of Field Robotics, EarlyView.
ABSTRACT People with physical disabilities face significant mobility challenges while climbing uneven surfaces and staircases. In these circumstances, traditional wheelchairs do not provide stable, safely controlled mobility, underscoring the importance of building superior stair‐climbing wheelchairs for both medical and infrastructure purposes.
Gopisetti Manikanta, S. M. Abhinandan, Anand Reddy, G. Chandana, Divya, P. Anil Kumar, Ch. Venkata Rao, Ashish Garg, Ravi C. Soni, Jogendra Kumar, Bhargav Akkinepally   +10 more
wiley   +1 more source

Six-axis decentralized control design for spacecraft formation flying mission [PDF]

, 2006
This contribution addresses the control design for the three-spacecraft formation flying interferometry mission Pegase. The operational mode considered is the high-precision nulling phase.
Sebastian Gaulocher, Daniel Alazard, Sebastian L. Gaulocher, Pittet, Christelle, Jean-pierre Chretien, Chrétien, Jean-Pierre, Alazard, Daniel, Gaulocher, Sebastian, Christelle Pittet   +8 more
core   +1 more source

Embedded Interactions and Selective Disclosure: Network Effects on Conversations aboard Skylab

Symbolic Interaction, EarlyView.
How do absent others influence our interactions? We argue in this paper that interactions are embedded within networks formed by chains of specific relationships between known third parties. The anticipation of future interactions with external others conditions our interpretation of the current situation and affects our behavior in the interaction. We
Michael Schultz, Leslie DeChurch, Noshir Contractor   +2 more
wiley   +1 more source

Decentralized attitude synchronization of spacecraft formations under complex communication topology

Advances in Mechanical Engineering, 2016
The attitude synchronizing of formation flying spacecrafts is an essential ingredient in almost all practical situations. However, thus far no control scheme was proposed for synchronizing the attitude of multiple spacecraft without a prescribed ...
Zhipeng Wang, Zhaowei Sun, Xiande Wu, Haichao Liang, Jianying Wang   +4 more
doaj   +1 more source

Tailoring Model‐Based Systems Engineering for Sub‐100 g PlanarSats: A Power‐First View Stack

Systems Engineering, EarlyView.
ABSTRACT This paper addresses how to apply model‐based systems engineering (MBSE) to ultrasmall planar satellites under severe power and resource constraints. PlanarSats are sub‐100‐gram spacecraft built as single printed‐circuit boards where the same surface must host both electronics and solar cells, so power generation, geometry, and component ...
Mehmet Şevket Uludaǧ, Alim Rüstem Aslan   +1 more
wiley   +1 more source

The Rational Design of Space Agreements: How Bilateralism Shapes Powerful States' Design Preferences

Regulation &Governance, EarlyView.
ABSTRACT The global governance of outer space relies heavily on international agreements, yet the institutional forms of these agreements remain underexplored. This article introduces a new dataset on various design features of 952 space agreements, offering the first large‐N overview of institutional design in space governance.
Jean‐Frédéric Morin, Philippe Evoy, Cynthia Couette   +2 more
wiley   +1 more source

Finite-Time Orbit Control for Spacecraft Formation with External Disturbances and Limited Data Communication

International Journal of Aerospace Engineering, 2022
This work addresses the finite-time orbit control problem for spacecraft formation flying with external disturbances and limited data communication. A hysteretic quantizer is employed for data quantization in the controller-actuator channel to decrease ...
Lei Xing, Dechao Ran, Jian Zhang, Li Huang   +3 more
doaj   +1 more source

A hardware-in-the-loop testbed for spacecraft formation flying applications [PDF]

2001 IEEE Aerospace Conference Proceedings (Cat. No.01TH8542), 2002
The Formation Flying Test Bed (FFTB) at NASA Goddard Space Flight Center (GSFC) is being developed as a modular, hybrid dynamic simulation facility employed for end-to-end guidance, navigation, and control (GNC including a high-fidelity GPS simulator which has been a fundamental component of the Guidance, Navigation, and Control Center's GPS Test ...
openaire   +2 more sources