Combining Sensors Information to Enhance Pneumatic Grippers Performance

The gripper is the far end of a robotic arm. It is responsible for the contacts between the robot itself and all the items present in a work space, or even in a social space. Therefore, to provide grippers with intelligent behaviors is fundamental, especially when the robot has to interact with human beings. As shown in this article, we built an instrumented pneumatic gripper prototype that relies on different sensors’ information. Thanks to such information, the gripper prototype was able to detect the position of a given object in order to grasp it, to safely keep it between its fingers and to avoid slipping in the case of any object movement, even very small. The gripper performance was evaluated by means of a generic grasping algorithm for robotic grippers, implemented in the form of a state machine. Several slip tests were carried out on the pneumatic gripper, which showed a very fast response time and high reliability. Objects of various size, shape and hardness were employed to reproduce different grasping scenarios. We demonstrate that, through the use of force, torque, center of pressure and proximity information, the behavior of the developed pneumatic gripper prototype outperforms the one of the traditional pneumatic gripping devices.

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Predictive, Deadbeat, and Combined Controls

10.1093/oso/9780198742968.003.0005 ◽

2018 ◽

Author(s):

Sadegh Vaez-Zadeh

Keyword(s):

Control Systems ◽

Predictive Control ◽

Direct Torque Control ◽

Fast Response ◽

Torque Control ◽

Control Methods ◽

Electric Motors ◽

Operating Cycle ◽

Combined Control ◽

The One

In this chapter, three control methods recently developed for or applied to electric motors in general and to permanent magnet synchronous (PMS) motors, in particular, are presented. The methods include model predictive control (MPC), deadbeat control (DBC), and combined vector and direct torque control (CC). The fundamental principles of the methods are explained, the machine models appropriate to the methods are derived, and the control systems are explained. The PMS motor performances under the control systems are also investigated. It is elaborated that MPC is capable of controlling the motor under an optimal performance according to a defined objective function. DBC, on the other hand, provides a very fast response in a single operating cycle. Finally, combined control produces motor dynamics faster than one under VC, with a smoother performance than the one under DTC.

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Freedom and Responsibility in Neoplatonist Thought

10.1093/oso/9780198824831.001.0001 ◽

2020 ◽

Author(s):

Ursula Coope

Keyword(s):

First Principle ◽

Human Beings ◽

Human Soul ◽

The One ◽

Freedom And Responsibility

The Neoplatonists have a perfectionist view of freedom: an entity is free to the extent that it succeeds in making itself good. Free entities are wholly in control of themselves: they are self-determining, self-constituting, and self-knowing. Neoplatonist philosophers argue that such freedom is only possible for nonbodily things. The human soul is free insofar as it rises above bodily things and engages in intellection, but when it turns its desires to bodily things, it is drawn under the sway of fate and becomes enslaved. This book discusses this notion of freedom, and its relation to questions about responsibility. It explains the important role of notions of self-reflexivity in Neoplatonist accounts of both freedom and responsibility. Part I sets out the puzzles Neoplatonist philosophers face about freedom and responsibility and explains how these puzzles arise from earlier discussions. Part II looks at the metaphysical underpinnings of the Neoplatonist notion of freedom (concentrating especially on the views of Plotinus and Proclus). In what sense (if any) is the ultimate first principle of everything (the One) free? If everything else is under this ultimate first principle, how can anything other than the One be free? What is the connection between freedom and nonbodiliness? Part III looks at questions about responsibility, arising from this perfectionist view of freedom. Why are human beings responsible for their behaviour, in a way that other animals are not? If we are enslaved when we act viciously, how can we be to blame for our vicious actions and choices?

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Networking for Cloud Robotics: The DewROS Platform and Its Application

Journal of Sensor and Actuator Networks ◽

10.3390/jsan10020034 ◽

2021 ◽

Vol 10 (2) ◽

pp. 34

Author(s):

Alessio Botta ◽

Jonathan Cacace ◽

Riccardo De Vivo ◽

Bruno Siciliano ◽

Giorgio Ventre

Keyword(s):

Response Time ◽

Large Data ◽

Cloud Services ◽

Cloud Provider ◽

Human Beings ◽

Minimal Impact ◽

Network Connection ◽

Cloud Robotics ◽

Networking Technologies ◽

The Impact

With the advances in networking technologies, robots can use the almost unlimited resources of large data centers, overcoming the severe limitations imposed by onboard resources: this is the vision of Cloud Robotics. In this context, we present DewROS, a framework based on the Robot Operating System (ROS) which embodies the three-layer, Dew-Robotics architecture, where computation and storage can be distributed among the robot, the network devices close to it, and the Cloud. After presenting the design and implementation of DewROS, we show its application in a real use-case called SHERPA, which foresees a mixed ground and aerial robotic platform for search and rescue in an alpine environment. We used DewROS to analyze the video acquired by the drones in the Cloud and quickly spot signs of human beings in danger. We perform a wide experimental evaluation using different network technologies and Cloud services from Google and Amazon. We evaluated the impact of several variables on the performance of the system. Our results show that, for example, the video length has a minimal impact on the response time with respect to the video size. In addition, we show that the response time depends on the Round Trip Time (RTT) of the network connection when the video is already loaded into the Cloud provider side. Finally, we present a model of the annotation time that considers the RTT of the connection used to reach the Cloud, discussing results and insights into how to improve current Cloud Robotics applications.

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Dual-Cation Electrolytes Crosslinked with MXene for High-Performance Electrochromic Devices

Nanomaterials ◽

10.3390/nano11040874 ◽

2021 ◽

Vol 11 (4) ◽

pp. 874

Author(s):

Soyoung Bae ◽

Youngno Kim ◽

Jeong Min Kim ◽

Jung Hyun Kim

Keyword(s):

Ionic Conductivity ◽

Response Time ◽

Indium Tin Oxide ◽

High Performance ◽

Fast Response ◽

High Ionic Conductivity ◽

Electrochromic Device ◽

Fast Response Time ◽

Coloration Efficiency ◽

Conduction Pathway

MXene, a 2D material, is used as a filler to manufacture polymer electrolytes with high ionic conductivity because of its unique sheet shape, large specific surface area and high aspect ratio. Because MXene has numerous -OH groups on its surface, it can cause dehydration and condensation reactions with poly(4-styrenesulfonic acid) (PSSA) and consequently create pathways for the conduction of cations. The movement of Grotthuss-type hydrogen ions along the cation-conduction pathway is promoted and a high ionic conductivity can be obtained. In addition, when electrolytes composed of a conventional acid or metal salt alone is applied to an electrochromic device (ECD), it does not bring out fast response time, high coloration efficiency and transmittance contrast simultaneously. Therefore, dual-cation electrolytes are designed for high-performance ECDs. Bis(trifluoromethylsulfonyl)amine lithium salt (LiTFSI) was used as a source of lithium ions and PSSA crosslinked with MXene was used as a source of protons. Dual-Cation electrolytes crosslinked with MXene was applied to an indium tin oxide-free, all-solution-processable ECD. The effect of applying the electrolyte to the device was verified in terms of response time, coloration efficiency and transmittance contrast. The ECD with a size of 5 × 5 cm2 showed a high transmittance contrast of 66.7%, fast response time (8 s/15 s) and high coloration efficiency of 340.6 cm2/C.

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Bio-Inspired Modality Fusion for Active Speaker Detection

Applied Sciences ◽

10.3390/app11083397 ◽

2021 ◽

Vol 11 (8) ◽

pp. 3397

Author(s):

Gustavo Assunção ◽

Nuno Gonçalves ◽

Paulo Menezes

Keyword(s):

Superior Colliculus ◽

Visual Information ◽

Human Beings ◽

Validation Process ◽

Detection Approach ◽

Wide Range ◽

Speaker Detection ◽

The One ◽

The Brain ◽

Fusion Ability

Human beings have developed fantastic abilities to integrate information from various sensory sources exploring their inherent complementarity. Perceptual capabilities are therefore heightened, enabling, for instance, the well-known "cocktail party" and McGurk effects, i.e., speech disambiguation from a panoply of sound signals. This fusion ability is also key in refining the perception of sound source location, as in distinguishing whose voice is being heard in a group conversation. Furthermore, neuroscience has successfully identified the superior colliculus region in the brain as the one responsible for this modality fusion, with a handful of biological models having been proposed to approach its underlying neurophysiological process. Deriving inspiration from one of these models, this paper presents a methodology for effectively fusing correlated auditory and visual information for active speaker detection. Such an ability can have a wide range of applications, from teleconferencing systems to social robotics. The detection approach initially routes auditory and visual information through two specialized neural network structures. The resulting embeddings are fused via a novel layer based on the superior colliculus, whose topological structure emulates spatial neuron cross-mapping of unimodal perceptual fields. The validation process employed two publicly available datasets, with achieved results confirming and greatly surpassing initial expectations.

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A Full-Range Flexible and Printed Humidity Sensor Based on a Solution-Processed P(VDF-TrFE)/Graphene-Flower Composite

Nanomaterials ◽

10.3390/nano11081915 ◽

2021 ◽

Vol 11 (8) ◽

pp. 1915

Author(s):

Shenawar Ali Khan ◽

Muhammad Saqib ◽

Muhammad Muqeet Rehman ◽

Hafiz Mohammad Mutee Ur Rehman ◽

Sheik Abdur Rahman ◽

...

Keyword(s):

Active Layer ◽

Humidity Sensor ◽

High Reliability ◽

Full Range ◽

High Sensitivity ◽

Fast Response ◽

Considerable Change ◽

Relative Humidity Range ◽

Response And Recovery ◽

Proportional Relationship

A novel composite based on a polymer (P(VDF-TrFE)) and a two-dimensional material (graphene flower) was proposed as the active layer of an interdigitated electrode (IDEs) based humidity sensor. Silver (Ag) IDEs were screen printed on a flexible polyethylene terephthalate (PET) substrate followed by spin coating the active layer of P(VDF-TrFE)/graphene flower on its surface. It was observed that this sensor responds to a wide relative humidity range (RH%) of 8–98% with a fast response and recovery time of 0.8 s and 2.5 s for the capacitance, respectively. The fabricated sensor displayed an inversely proportional response between capacitance and RH%, while a directly proportional relationship was observed between its impedance and RH%. P(VDF-TrFE)/graphene flower-based flexible humidity sensor exhibited high sensitivity with an average change of capacitance as 0.0558 pF/RH%. Stability of obtained results was monitored for two weeks without any considerable change in the original values, signifying its high reliability. Various chemical, morphological, and electrical characterizations were performed to comprehensively study the humidity-sensing behavior of this advanced composite. The fabricated sensor was successfully used for the applications of health monitoring and measuring the water content in the environment.

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Two Conceptions of Second Nature

Open Philosophy ◽

10.1515/opphil-2020-0005 ◽

2020 ◽

Vol 3 (1) ◽

pp. 68-80 ◽

Cited By ~ 1

Author(s):

Georg W. Bertram

Keyword(s):

The Other ◽

Human Beings ◽

Open Future ◽

Second Nature ◽

Other Hand ◽

The World ◽

Cognitive Activities ◽

The Open Future ◽

The One ◽

First Nature

AbstractThe concept of second nature promises to provide an explanation of how nature and reason can be reconciled. But the concept is laden with ambiguity. On the one hand, second nature is understood as that which binds together all cognitive activities. On the other hand, second nature is conceived of as a kind of nature that can be changed by cognitive activities. The paper tries to investigate this ambiguity by distinguishing a Kantian conception of second nature from a Hegelian conception. It argues that the idea of a transformation from a being of first nature into a being of second nature that stands at the heart of the Kantian conception is mistaken. The Hegelian conception demonstrates that the transformation in question takes place within second nature itself. Thus, the Hegelian conception allows us to understand the way in which second nature is not structurally isomorphic with first nature: It is a process of ongoing selftransformation that is not primarily determined by how the world is, but rather by commitments out of which human beings are bound to the open future.

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Doped Emitting Cesium Silver Halides as X‐Ray Scintillator with Fast Response Time, High Absorption Coefficient, and Light Yield

Advanced Photonics Research ◽

10.1002/adpr.202100066 ◽

2021 ◽

pp. 2100066

Author(s):

Jia-Li Yao ◽

Zi-Xu Zhang ◽

Xiao-Qi Sun ◽

Tong Chang ◽

Jing-Fu Guo ◽

...

Keyword(s):

Absorption Coefficient ◽

Response Time ◽

Light Yield ◽

Fast Response ◽

Silver Halides ◽

X Ray ◽

Fast Response Time ◽

High Absorption Coefficient ◽

High Absorption

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Posturography with head movements in the assessment of balance in chronic unilateral vestibular lesions

Scientific Reports ◽

10.1038/s41598-021-85745-x ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Magdalena Janc ◽

Mariola Sliwinska-Kowalska ◽

Piotr Politanski ◽

Marek Kaminski ◽

Magdalena Jozefowicz-Korczynska ◽

...

Keyword(s):

High Reliability ◽

Low Frequency ◽

Random Order ◽

Head Movements ◽

Canal Paresis ◽

Eyes Closed ◽

Static Posturography ◽

Unstable Surface ◽

Novel Method ◽

The One

AbstractThe aim of our study was to validate the method of head-shake static posturography (HS-posturography) in healthy individuals and to establish the value of this novel method in the diagnostics of patients with unilateral vestibular lesion (UV). The study included 202 participants divided into two groups, one consisting of 133 patients with canal paresis CP > 19% and one of 69 healthy subjects. Participant was tested according to the standard protocol of static posturography (SP), and with head movements of 0.3 Hz (HS 40), 0.6 Hz (HS 70) in random order controlled by a metronome. HS-posturography revealed a similar repeatability and internal consistency as the standard posturography. In patients with UV, 4th condition revealed higher sensitivity (74%) and specificity (71%) in HS 40 than in the standard posturography (67%, 65% respectively) and HS 70 (54%, 70% respectively). Static posturography and HS- posturography revealed a high reliability of the testing method. The head movements added to static posturography improve the sensitivity and specificity of the method in group with vestibular impairment. The most important test for that purpose seems to be the one on unstable surface with the eyes closed, with low frequency of head movements.

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