158 research outputs found
TRACKING CONTROL OF A SPACE VEHICLE WITH DUAL-ARM ROBOTIC MANIPULATOR USING SLIDING MODE CONTROL
No full textThe use of free-flying space manipulators for the capture of noncooperative targets in space is of great interest, but controlling the spacecraft bus and manipulator at the same time can prove to be a challenging task due to the coupling dynamics. In this paper, the dynamics of a rigid body-space vehicle with two robotic manipulators is studied. A sliding mode control is proposed to account for the coupling of the base spacecraft and the manipulators, and a variational integrator is used in dynamic propagation to ensure that the geometric properties of the system are preserved. The asymptotic stability of the control law is proven through the Lyapunov direct method. Numerical simulations show that the manipulator successfully approaches the designated contact points on the target surface under the designated control action
STOCHASTIC SPACECRAFT NAVIGATION AND CONTROL IN LIE GROUP SE(3) AROUND SMALL IRREGULAR BODIES
No full textBiodegradable Sandstone: What are the possibilities of a biodegradable Sandstone?
No full textThe research and the development of biodegradable Sandstone at TU Delft Architecture, Delft. This study was aimed to test the biodegradable Sandstone and develop a method to improve the quality of life of the refugee camp by using biodegradable Standstone. The subject of this study was selected by Mustafa Nazari, he discovered biodegradable Sandstone during the study. In the first part, data was collected about the problem statement and solution by doingliterature study. Then doing experiments to discover the properties of this material. In the designing phase will be determined of it possible is to create a temporary housing by use biodegradable Sandstone.The results of this study make clear it is possible to create a temporary house by using specially designed bricks which are made of Biodegradable Sandstone.Architecture, Urbanism and Building Sciences | Building Technolog
Corrigendum: Sherkatolabbasieh H, Hagh-Nazari L, Shafiezadeh S, Goodarzi N, Zangeneh MM, Zangeneh A. Ameliorative effects of the ethanolic extract of Allium saralicum R.M. Fritsch on CCl4-induced nephrotoxicity in mice: A stereological examination. Arch Biol Sci. 2017;69(3): 535-43. https://doi.org/10.2298/ABS160914129S
No full textThe corresponding author of the article Sherkatolabbasieh H, Hagh-Nazari L,
Shafiezadeh S, Goodarzi N, Zangeneh MM, Zangeneh A. Ameliorative effects of
the ethanolic extract of Allium saralicum R.M. Fritsch on CCl4-induced
nephrotoxicity in mice: A stereological examination. Arch Biol Sci.
2017;69(3):535-43 has requested to change the affiliations of the authors. Link to the corrected article 10.2298/ABS160914129S</u
Flexible Body Control Using Fiber Optic Sensors, Florida Space Grant Consortium
No full textThis project would build on previous research that developed the dynamics formulation and control of a rigid-flexible system. A cantilevered beam attached to a rotating central body is considered and analyzed through the finite element method. A set of matrix differential equations are obtained to describe the dynamic behavior of the system, and a control law based on a Lyapunov function is obtained and applied to the system. The development of this dynamics formulation and control also considers the rigid-flexible coupling present in the system. The control law is designed such that the system can achieve and maintain a set of desired states for the central rigid body and flexible structure. The experimental measurements obtained from the implementation of FOS sensors on the flexible body and inertial sensors on the rigid body will be utilized as the input in this control design. The research portion of the project is anticipated to require a one or two graduate student research assistants and part time academic advisor over a 1-year period
Reconfigurable Guidance and Control Systems for Emerging On-Orbit Servicing, Assembly, and Manufacturing (OSAM) Space Vehicles
No full textDynamic response to emergent situations is a necessity in the on-orbit servicing, assembly, and manufacturing (OSAM) field, because traditional on-orbit guidance and control (G&C) cannot respond efficiently and effectively to such dynamic situations (i.e., they are based on either constant mass or diagonal matrix of inertia). In these circumstances, the current challenge is to develop modeling strategies and control systems that exhibit intelligence, robustness and adaptation to the environment changes and disturbances (e.g., uncertainties, constraints, and flexible dynamics). Note that the current state- of-the-art methods do not offer a reliable, accurate framework for real-time, optimal accommodation of constraints in the system dynamics that accounts for orbital-attitude coupling in the motion of the bodies without encountering singularity or non-uniqueness issues. In this project, the ControlX team with ERAU partnership will develop agile, reconfigurable, and resilient dynamics and G&C algorithms for on-orbit servicing to capture a broad set of OSAM applications such as remediation of resident space object (RSO) (e.g., via de-orbiting, recycle, end-of-life servicing, satellite refueling, etc.) using effective tools and methods involving geometric mechanics, constrained G&C synthesis, and reconfigurable robotic manipulators (RRMs). The proposed work in this Phase I includes reconfigurable systems for on-orbit servicing, assembly, and manufacturing with learning control methods that minimizes tracking error of the end-effector of the RRM in the presence of uncertainties, optimizes configuration, and accommodates constraint-changing scenarios. Our developments will avoid singularity; not rely on the concept of costates or Lagrange multipliers that are restrictive; handle system uncertainties while enforcing the constraints; use RRMs in different tasks (recycle, debris removing, maintenance, etc.); not need in sensors or exact model knowledge for robotic arms. Specifically, constrained space vehicle control (predicated on Udwadia and Kalaba (UK) formalism) will offer not only accurate and resilient design but also reconfigurability in that G&C algorithms can easily be modified to suit a wide spectrum of OSAM applications. ControlX team will also consider the feasibility of hardware implementation. The selection of sensors, actuators, and on-board computers will be an important trade-off between among size, weight, and power (SWaP) constraints, reliability, and computing performance. A real-time operating system (RTOS) is planned to meet timing and memory management constraints, partitioning hardware resources to control software application interactions. An analysis suite for the autonomous system implementation, based on system modeling and learning techniques, will provide onboard analysis, enabling decision-making as to whether the system can continue to meet mission requirements
Ethical Aspect of Infertility Treatment through Surrogacy based on Utilitarian Principle: Surrogacy & utilitarianism
No full textBackground and Aim: One of the questions that may be raised about infertility treatment through surrogacy is the ethicality of this approach. There are many methods for the ethical clarification of the medical issues. If we accept the utilitarian philosophers’ views stating that an ethical measure is beneficial to the community and individuals, we may come up with the question whether the actions of the infertile couples or surrogate mother are considered ethical since these actions are beneficial for both individuals and community. Regarding this, the present study aimed to evaluate the infertile treatment through surrogacy based on the ethical theories of utilitarianism.
Materials and Methods: This analytical-descriptive research gathered relevant data in a literature search. After a description of the fundamentals and definitions, ethical texts were subsequently analyzed and one of the viewpoints regarding of Infertility Treatment through Surrogacy Based on Utilitarian Principle was selected.
Ethical Considerations: Ethical principles were considered in searching and citing the literature.
Findings: According to the rule utilitarianism, the ethicality of an action is measured based on its collective benefit and its placement in an ethical principle framework. Therefore, we cannot treat surrogacy like an accepted ethical principle, such as sacrifice, and provide a general rule for the determination of the effect of different social, cultural, economic, and political factors on the people involved in this act. However, the use of this method in different situations and for various people could be very beneficial and be considered ethical.
Conclusion: Although the comprehensive investigation of the harmful use of surrogacy has not been accomplished, the various problems and factors affecting the evaluation of the overall profit and loss of this act grab the possibility of determining its morality as a valid rule in the rule-based ethics. However, such a provision is justified in the utilitarian and pragmatic ethical systems.
*Corresponding Author: Saeid Nazari Tavakkoli; Email: [email protected]; ORCID: https://orcid.org/0000-0002-6398-521X
Please cite this article as: Nazari Tavakkoli A, Karachian Sani F. Ethical Aspect of Infertility Treatment through Surrogacy based on Utilitarian Principle. Bioeth Health Law J. 2021; 1:1-8: (e17). http://doi.org/10.22037/bhl.v1i1.3817
Utilizing Topology Data to Facilitate Geometric Control of a Spacecraft During Lunar Landing
No full textPredispersal seed predation by a coleophorid on the threatened Gulf of St. Lawrence aster
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