scholarly journals Electronic Hovercraft

2021 ◽  
Vol 9 (VI) ◽  
pp. 4351-4359
Author(s):  
G. Jayanth Kumar
Keyword(s):  
Optic Flow ◽  
Autonomous Vehicles ◽  
Forward Speed ◽  
Robotic Platform ◽  
Flying Insects ◽  
Unpredictable Environments ◽  
Speed Up ◽  
And Control ◽  
Small Autonomous Vehicles ◽  
First Time

The small autonomous vehicles of the future will have to navigate close to obstacles in highly unpredictable environments. Risky tasks of this kind may require novel sensors and control methods that differ from conventional approaches. Recent ethological findings have shown that complex navigation tasks such as obstacle avoidance and speed control are performed by flying insects on the basis of optic flow (OF) cues, although insects' compound eyes have a very poor spatial resolution. The implementation of an optic flow-based autopilot on a fully autonomous hovercraft. Tests were performed on this small (878-gram) innovative robotic platform in straight and tapered corridors lined with natural panoramas. A bilateral OF regulator controls the robot's forward speed (up to 0.8m/s), while a unilateral OF regulator controls the robot's clearance from the two walls. A micro-gyrometer and a tiny magnetic compass ensure that the hovercraft travels forward in the corridor without yawing. The lateral OFs are measured by two minimalist eyes mounted sideways opposite to each other. For the first time, the hovercraft was found to be capable of adjusting both its forward speed and its clearance from the walls, in both straight and tapered corridors, without requiring any distance or speed measurements, that is, without any need for on-board rangefinders or tachometers.

scholarly journals A dϕ-Strategy: Facilitating Dual-Formation Control of a Virtually Connected Team

2017 ◽  
Vol 2017 ◽  
pp. 1-17 ◽  
Author(s):  
Bibhya Sharma ◽  
Jito Vanualailai ◽  
Avinesh Prasad
Keyword(s):  
Autonomous Vehicles ◽  
Formation Control ◽  
Field Method ◽  
Mobile Manipulators ◽  
End Effector ◽  
Planning And Control ◽  
Potential Field Method ◽  
Control Scheme ◽  
And Control ◽  
First Time

This paper describes the design of new centralized acceleration-based controllers for the multitask problem of motion planning and control of a coordinated lead-carrier team fixed in a dual-formation within an obstacle-ridden environment. A dϕ-strategy, where d and ϕ are Euclidean measures with respect to the lead robot, is developed to ensure virtual connectivity of the carrier robots to the lead robot. This connectivity, built into the system itself, inherently ensures globally rigid formation between each lead-carrier pair of the team. Moreover, a combination of target configuration, dϕ-strategy, orientation consensus, and avoidance of end-effector of robots results in a second, locally rigid formation (not infinitesimally rigid). Therefore, for the first time, a dual-formation control problem of a lead-carrier team of mobile manipulators is considered. This and other kinodynamic constraints have been treated simultaneously via the overarching Lyapunov-based control scheme, essentially a potential field method favored in the field of robotics. The formulation of this new scheme, demonstrated effectively via computer simulations, is timely, given that the current proposed engineering solutions, allowing autonomous vehicles on public roads, include the development of special lanes imbued with special sensors and wireless technologies.

The Effects of Corporate Ownership on Public Accountants' Professionalism and Ethics

2002 ◽  
Vol 16 (2) ◽  
pp. 109-124 ◽  
Author(s):  
William E. Shafer ◽  
D. Jordan Lowe ◽  
Timothy J. Fogarty
Keyword(s):  
Current Trend ◽  
Auditor Independence ◽  
Corporate Ownership ◽  
Negative Effects ◽  
Public Accounting ◽  
Corporate Acquisitions ◽  
Accounting Professionals ◽  
Research Questions ◽  
And Control ◽  
First Time

The current trend toward corporate acquisitions of CPA firms poses potential threats to the autonomy and ethical standards of public accounting professionals. This recent consolidation movement suggests that for the first time a significant number of public accounting professionals are subject to the supervision and control of nonprofessionals. In addition to acknowledging the potential threats to auditor independence and objectivity, this paper suggests that these new organizational arrangements for the provision of public accounting services have other negative effects on professionalism and ethics such as desensitizing CPAs to traditional professional values, and subverting professional institutions to the goals of corporate employers. This paper develops a framework that identifies several specific research questions related to the effects of corporate ownership on professionalism and ethics in public accounting.

Autonomous Vehicles in the Mobility System

2020 ◽  
pp. 500-514
Author(s):  
Thilo von Pape
Keyword(s):  
Artificial Intelligence ◽  
Mobile Phones ◽  
Mobile Communication ◽  
Autonomous Vehicles ◽  
Communication Research ◽  
Collective Control ◽  
System P ◽  
Mobility System ◽  
And Control ◽  
Transportation Technologies

This chapter discusses how autonomous vehicles (AVs) may interact with our evolving mobility system and what they mean for mobile communication research. It juxtaposes a conceptualization of AVs as manifestations of automation and artificial intelligence with an analysis of our mobility system as a historically grown hybrid of communication and transportation technologies. Since the emergence of railroad and telegraph, this system has evolved on two layers: an underlying infrastructure to power and coordinate the movements of objects, people, and ideas in industrially scaled speeds, volumes, and complexity and an interface to seamlessly access this infrastructure and control it. AVs are poised to further enhance the seamlessness which mobile phones and cars already lent to mobility. But in assuming increasingly sophisticated control tasks, AVs also disrupt an established shift toward individual control, demanding new interfaces to enable higher levels of individual and collective control over the mobility infrastructure.

scholarly journals Bio-inspired Coordination and Control of Autonomous Vehicles in Future Manufacturing and Goods Transportation

2020 ◽  
Vol 53 (2) ◽  
pp. 10861-10866
Author(s):  
Constantin F. Caruntu ◽  
Carlos M. Pascal ◽  
Anca Maxim ◽  
Ovidiu Pauca
Keyword(s):  
Autonomous Vehicles ◽  
And Control ◽  
Coordination And Control

scholarly journals Ear-Bot: Locust Ear-on-a-Chip Bio-Hybrid Platform

Sensors ◽  
2021 ◽  
Vol 21 (1) ◽  
pp. 228
Author(s):  
Idan Fishel ◽  
Yoni Amit ◽  
Neta Shvil ◽  
Anton Sheinin ◽  
Amir Ayali ◽  
...  
Keyword(s):  
Proof Of Concept ◽  
Robotic Platform ◽  
Neural Signals ◽  
Technological Approach ◽  
Hybrid Platform ◽  
And Control ◽  
Robust Sensing ◽  
Robotic Sensing ◽  
Sound Pulses

During hundreds of millions of years of evolution, insects have evolved some of the most efficient and robust sensing organs, often far more sensitive than their man-made equivalents. In this study, we demonstrate a hybrid bio-technological approach, integrating a locust tympanic ear with a robotic platform. Using an Ear-on-a-Chip method, we manage to create a long-lasting miniature sensory device that operates as part of a bio-hybrid robot. The neural signals recorded from the ear in response to sound pulses, are processed and used to control the robot’s motion. This work is a proof of concept, demonstrating the use of biological ears for robotic sensing and control.

scholarly journals Stochastic Inverse Identification of Nonlinear Roll Damping Moment of a Ship Moving at Nonzero-Forward Speeds

2012 ◽  
Vol 2012 ◽  
pp. 1-22 ◽  
Author(s):  
S. L. Han ◽  
Takeshi Kinoshita
Keyword(s):  
Nonlinear Damping ◽  
Rolling Motion ◽  
Forward Speed ◽  
Roll Damping ◽  
Nonparametric Approach ◽  
Nonlinear Responses ◽  
Different Types ◽  
Experimental Trials ◽  
And Control ◽  
Ship Rolling

The nonlinear responses of ship rolling motion characterized by a roll damping moment are of great interest to naval architects and ocean engineers. Modeling and identification of the nonlinear damping moment are essential to incorporate the inherent nonlinearity in design, analysis, and control of a ship. A stochastic nonparametric approach for identification of nonlinear damping in the general mechanical system has been presented in the literature (Han and Kinoshits 2012). The method has been also applied to identification of the nonlinear damping moment of a ship at zero-forward speed (Han and Kinoshits 2013). In the presence of forward speed, however, the characteristic of roll damping moment of a ship is significantly changed due to the lift effect. In this paper, the stochastic inverse method is applied to identification of the nonlinear damping moment of a ship moving at nonzero-forward speed. The workability and validity of the method are verified with laboratory tests under controlled conditions. In experimental trials, two different types of ship rolling motion are considered: time-dependent transient motion and frequency-dependent periodic motion. It is shown that this method enables the inherent nonlinearity in damping moment to be estimated, including its reliability analysis.

scholarly journals Giving Birth With Epidural Analgesia: The Experience of First-Time Mothers

2012 ◽  
Vol 21 (1) ◽  
pp. 24-35 ◽  
Author(s):  
Ryoko Hidaka ◽  
Lynn Clark Callister
Keyword(s):  
Pain Management ◽  
Epidural Analgesia ◽  
Epidural Administration ◽  
Birth Experience ◽  
Management Options ◽  
Key Factor ◽  
Qualitative Descriptive ◽  
And Control ◽  
First Time ◽  
Experiences Of Women

The purpose of our qualitative descriptive study was to describe the birth experiences of women using epidural analgesia for pain management. We interviewed nine primiparas who experienced vaginal births. Five themes emerged: (a) coping with pain, (b) finding epidural administration uneventful, (c) feeling relief having an epidural, (d) experiencing joy, and (e) having unsettled feelings of ambivalence. Although epidural analgesia was found to be effective for pain relief and may contribute to some women’s satisfaction with the birth experience, it does not guarantee a quality birth experience. In order to support and promote childbearing women’s decision making, we recommend improved education on the variety of available pain management options, including their risks and benefits. Fostering a sense of caring, connection, and control in women is a key factor to ensure positive birth experiences, regardless of pain management method.

scholarly journals Discharge Properties of MST Neurons That Project to the Frontal Pursuit Area in Macaque Monkeys

2005 ◽  
Vol 94 (2) ◽  
pp. 1084-1090 ◽  
Author(s):  
Anne K. Churchland ◽  
Stephen G. Lisberger
Keyword(s):  
Optic Flow ◽  
Action Potentials ◽  
Rhesus Monkeys ◽  
Statistical Significance ◽  
Image Motion ◽  
Antidromic Activation ◽  
Medial Superior Temporal ◽  
Mst Neurons ◽  
Direction Tuning ◽  
And Control

We have used antidromic activation to determine the functional discharge properties of neurons that project to the frontal pursuit area (FPA) from the medial-superior temporal visual area (MST). In awake rhesus monkeys, MST neurons were considered to be activated antidromically if they emitted action potentials at fixed, short latencies after stimulation in the FPA and if the activation passed the collision test. Antidromically activated neurons ( n = 37) and a sample of the overall population of MST neurons ( n = 110) then were studied during pursuit eye movements across a dark background and during laminar motion of a large random-dot texture and optic flow expansion and contraction during fixation. Antidromically activated neurons showed direction tuning during pursuit (25/37), during laminar image motion (21/37), or both (16/37). Of 27 neurons tested with optic flow stimuli, 14 showed tuning for optic flow expansion ( n = 10) or contraction ( n = 4). There were no statistically significant differences in the response properties of the antidromically activated and control samples. Preferred directions for pursuit and laminar image motion did not show any statistically significant biases, and the preferred directions for eye versus image motion in each sample tended to be equally divided between aligned and opposed. There were small differences between the control and antidromically activated populations in preferred speeds for laminar motion and optic flow; these might have reached statistical significance with larger samples of antidromically activated neurons. We conclude that the population of MST neurons projecting to the FPA is highly diverse and quite similar to the general population of neurons in MST.

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