virtual control
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2022 ◽  
Vol 2022 ◽  
pp. 1-11
Author(s):  
Ao He ◽  
Yinong Zhang ◽  
Huimin Zhao ◽  
Ban Wang ◽  
Zhenghong Gao

This paper proposes an adaptive fault-tolerant control strategy for a hybrid vertical take-off and landing (VTOL) unmanned aerial vehicle (UAV) to simultaneously compensate actuator faults and model uncertainties. With the proposed adaptive control schemes, both actuator faults and model uncertainties can be accommodated without the knowledge of fault information and uncertainty bounds. The proposed control scheme is constructed with two separate control modules. The low-level control allocation module is used to distribute the virtual control signals among the available redundant actuators. The high-level control module is constructed with an adaptive sliding mode controller, which is employed to maintain the overall system tracking performance in both faulty and uncertain conditions. In the case of actuator faults and model uncertainties, the adaptive scheme will be triggered to generate more virtual control signals to compensate the virtual control error and maintain the desired system tracking performance. The effectiveness of the proposed control strategy is validated through comparative simulation tests under different faulty and uncertain scenarios.


2021 ◽  
Vol 24 (5) ◽  
pp. 889-901
Author(s):  
Михаил Васильевич Михайлюк ◽  
Дмитрий Алексеевич Кононов ◽  
Дмитрий Михайлович Логинов

The technology of modelling various situations in virtual environment systems, which are computer three-dimensional models of a real or artificial environment, is discussed. The user can view these scenes directly on the computer screen, wall screen, in a stereo glasses, virtual reality glasses, etc. He can also move inside a virtual scene and interact with its objects. In turn, the environment can also change. This allows modelling of various situations (situation modelling) in the virtual environment system. With such modelling, some static or dynamic situation is set in the virtual environment system in which the operator must perform the tasks assigned to him. A mechanism for setting situations by changing a virtual three-dimensional scene using configuration files and virtual control panels is proposed. A special language has been developed for writing configuration files, and a special editor has been developed for creating virtual control panels. The approbation of the proposed methods is presented on the examples of two virtual scenes: a training ground for mobile robots and a jet backpack for the rescue of an astronaut in outer space.


2021 ◽  
Vol 15 ◽  
Author(s):  
Felix Schoeller ◽  
Mark Miller ◽  
Roy Salomon ◽  
Karl J. Friston

In order to interact seamlessly with robots, users must infer the causes of a robot’s behavior–and be confident about that inference (and its predictions). Hence, trust is a necessary condition for human-robot collaboration (HRC). However, and despite its crucial role, it is still largely unknown how trust emerges, develops, and supports human relationship to technological systems. In the following paper we review the literature on trust, human-robot interaction, HRC, and human interaction at large. Early models of trust suggest that it is a trade-off between benevolence and competence; while studies of human to human interaction emphasize the role of shared behavior and mutual knowledge in the gradual building of trust. We go on to introduce a model of trust as an agent’ best explanation for reliable sensory exchange with an extended motor plant or partner. This model is based on the cognitive neuroscience of active inference and suggests that, in the context of HRC, trust can be casted in terms of virtual control over an artificial agent. Interactive feedback is a necessary condition to the extension of the trustor’s perception-action cycle. This model has important implications for understanding human-robot interaction and collaboration–as it allows the traditional determinants of human trust, such as the benevolence and competence attributed to the trustee, to be defined in terms of hierarchical active inference, while vulnerability can be described in terms of information exchange and empowerment. Furthermore, this model emphasizes the role of user feedback during HRC and suggests that boredom and surprise may be used in personalized interactions as markers for under and over-reliance on the system. The description of trust as a sense of virtual control offers a crucial step toward grounding human factors in cognitive neuroscience and improving the design of human-centered technology. Furthermore, we examine the role of shared behavior in the genesis of trust, especially in the context of dyadic collaboration, suggesting important consequences for the acceptability and design of human-robot collaborative systems.


2021 ◽  
pp. 105678792110434
Author(s):  
Alanna Bjorklund-Young ◽  
Angela R. Watson ◽  
Al Passarella

Increased charter school demand creates a critical need for reliable information on outcomes. Stanford’s Center for Research on Education Outcomes (CREDO) has a series of influential reports on charter schools using the virtual control record (VCR) method. However, the VCR method has been criticized and the validity of CREDO’s findings challenged, leading to confusion among stakeholders. In this paper, we synthesize charter school evaluation literature, explain CREDO’s methods as well as other evaluation methods, and consider the limitations of matching in this context. We find that, while the matching techniques are imperfect, they provide necessary information on the greatest percentage of charter school students.


Author(s):  
Michal Bilčík ◽  
Maximilián Strémy ◽  
Dominika Janíková ◽  
Dušan Horváth

Abstract This paper deals with the possibility of creating virtual C # models connectable to a virtual PLC of Siemens. The models will lead to the improvement and simplification of the online PLC education. Hardware solutions cost a lot of money, while using a software version of PLC leads to cheaper simulations. Paper presents the design and implementation of the virtual models, including the ways of the interconnection with PLCSIM, visualization and finally demonstration for the selected virtual model.


Author(s):  
K. Zhan ◽  
D. Fritsch ◽  
J. F. Wagner

Abstract. In this paper we propose a virtual control point based method for the registration of photogrammetry and computed tomography (CT) data. Because of the fundamentally different two data sources, conventional registration methods, such as manual control points registration or 3D local feature-based registration, are not suitable. The registration objective of our application is about 3D reconstructions of gyroscopes, which contain abundant geometric primitives to be fitted in the point clouds. In the first place, photogrammetry and CT scanning are applied, respectively, for 3D reconstructions. Secondly, our workflow implements a segmentation after obtaining the surface point cloud from the complete CT volumetric data. Then geometric primitives are fitted in this point cloud benefitting from the less complex cluster segments. In the next step, intersection operations of the parametrized primitives generates virtual points, which are utilized as control points for the transformation parameters estimation. A random sample consensus (RANSAC) method is applied to find the correspondences of both virtual control point sets using corresponding descriptors and calculates the transformation matrix as an initial alignment for further refining the registration. The workflow is invariant to pose, resolution, completeness and noise within our validation process.


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