Towards Finding the Optimum Position in the Visual Field for a Head Worn Display Used for Task Guidance with Non-registered Graphics

Where should a HWD be placed in a user's visual field? We present two studies that compare comfort, preference, task efficiency and accuracy for various HWD positions. The first study offsets a 9.2° horizontal field-of-view (FOV) display temporally (toward the ear) from 0° to 30° in 10° steps. 30° proves too uncomfortable while 10° is the most preferred position for a simple button-pushing game, corroborating results from previous single-task reading experiments. The second experiment uses a Magic Leap One to compare 10° x 10° FOV interfaces centered at line-of-sight, temporally offset 15° (center-right), inferiorly offset 15° (bottom-center), and offset in both directions (bottom-right) for an order picking task. The bottom-right position proved worst in terms of accuracy and several subjective metrics when compared to the line-of-sight position.

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A novel edge gradient algorithm for multiple mobile robots cooperative mapping in unknown environment

International Journal of Advanced Robotic Systems ◽

10.1177/1729881419860380 ◽

2019 ◽

Vol 16 (4) ◽

pp. 172988141986038

Author(s):

Huang Yiqing ◽

Wang Hui ◽

Wei Lisheng ◽

Gao Wengen ◽

Ge Yuan

Keyword(s):

Visual Field ◽

Mobile Robots ◽

Information Exchange ◽

Field Of View ◽

Gradient Algorithm ◽

Movement Direction ◽

Mapping Technique ◽

Map Building ◽

Multiple Mobile Robots ◽

Motion Behavior

This article presented a cooperative mapping technique using a novel edge gradient algorithm for multiple mobile robots. The proposed edge gradient algorithm can be divided into four behaviors such as adjusting the movement direction, evaluating the safety of motion behavior, following behavior, and obstacle information exchange, which can effectively prevent multiple mobile robots falling into concave obstacle areas. Meanwhile, a visual field factor is constructed based on biological principles so that the mobile robots can have a larger field of view when moving away from obstacles. Also, the visual field factor will be narrowed due to the obstruction of the obstacle when approaching an obstacle and the obtained map-building data are more accurate. Finally, three sets of simulation and experimental results demonstrate the performance superiority of the presented algorithm.

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Field of View and Skill Training of Table Tennis Teaching Based on Virtual Environment Technology

International Journal of Emerging Technologies in Learning (iJET) ◽

10.3991/ijet.v11i11.6240 ◽

2016 ◽

Vol 11 (11) ◽

pp. 60

Author(s):

Li Li

Keyword(s):

Visual Field ◽

Virtual Environment ◽

Skill Training ◽

Teaching Quality ◽

Field Of View ◽

Table Tennis ◽

Field Training

Focusing on the topic of improving the table tennis teaching quality with the visual field training, the test is to grab images repeatedly by using a camera in a speed of 119s, and the final result shows that it gets the correct hitting points on racket coordinating with correct racket angles, which verifies the effectiveness of the visual field training. Finally, it's concluded that the visual field training can improve the athletes' abilities of focus and judgment, and enhance their exercise stability.

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Subtraction of Bright Point Sources from Synthesis Images of the Epoch of Reionization

Publications of the Astronomical Society of Australia ◽

10.1071/as10023 ◽

2011 ◽

Vol 28 (1) ◽

pp. 46-57 ◽

Cited By ~ 23

Author(s):

B. Pindor ◽

J. S. B. Wyithe ◽

D. A. Mitchell ◽

S. M. Ord ◽

R. B. Wayth ◽

...

Keyword(s):

Active Galactic Nuclei ◽

Dynamic Range ◽

Low Frequency ◽

Neutral Hydrogen ◽

Galactic Nuclei ◽

Point Sources ◽

Field Of View ◽

Bright Point ◽

Line Of Sight ◽

Diffuse Background

AbstractBright point sources associated with extragalactic active galactic nuclei and radio galaxies are an important foreground for low-frequency radio experiments aimed at detecting the redshifted 21-cm emission from neutral hydrogen during the epoch of reionization. The frequency dependence of the synthesized beam implies that the sidelobes of these sources will move across the field of view as a function of observing frequency, hence frustrating line-of-sight foreground subtraction techniques. We describe a method for subtracting these point sources from dirty maps produced by an instrument such as the MWA. This technique combines matched filters with an iterative centroiding scheme to locate and characterize point sources in the presence of a diffuse background. Simulations show that this technique can improve the dynamic range of epoch-of-reionization maps by 2—3 orders of magnitude.

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Simulation study for the Stratospheric Inferred Winds (SIW) sub-millimeter limb sounder

10.5194/amt-2018-76 ◽

2018 ◽

Author(s):

Philippe Baron ◽

Donal Murtagh ◽

Patrick Eriksson ◽

Jana Mendrok ◽

Satoshi Ochiai ◽

...

Keyword(s):

Simulation Study ◽

Spectral Band ◽

Chemical Species ◽

Field Of View ◽

Emission Lines ◽

Horizontal Wind ◽

Line Of Sight ◽

Heterodyne Receiver ◽

Vertical Field ◽

Wind Measurements

Abstract. Stratospheric Inferred Winds (SIW) is a Swedish mini sub-millimeter limb sounder selected for the 2nd InnoSat platform launch planned near 2022. It is intended to fill the altitude gap between 30–70 km in atmospheric wind measurements and also aims at pursuing the limb observations of temperature and key atmospheric constituents between 10–90 km when current satellite missions are probably stopped. Line-of-sight winds are retrieved from the Doppler shift of the emission lines introduced by 5 the wind field. Observations will be performed with two antennas pointing toward the limb with perpendicular directions to reconstruct the 2-D horizontal wind vector. Each antenna has a vertical field of view of 5 km. The chosen spectral band near 655 GHz contains a dense group of strong O3 lines suitable for exploiting the small wind information in stratospheric spectra. Using both sidebands of the heterodyne receiver, a large number of chemical species will be measured including O3-isopotologues, H2O, HDO, HCl, ClO, N2O, HNO3, NO, NO2, HCN, CH3CN and HO2. This paper presents the simulation study for assessing the measurement performances. The line-of-sight winds are retrieved between 30–90 km with the best sensitivity between 35–70 km where the precision (1-sigma) is 5–10 m s−1 for a single scan. Similar performances can be obtained during day and night conditions except in the lower mesosphere where the photo-dissociation of O3 in day-time reduces the sensitivity by 50 % near 70 km. Profiles of O3, H2O and temperature are retrieved with a high precision up to 50 km (

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A survey on stereo vision-based autonomous navigation for multi-rotor MUAVs

Robotica ◽

10.1017/s0263574718000358 ◽

2018 ◽

Vol 36 (8) ◽

pp. 1225-1243 ◽

Cited By ~ 5

Author(s):

Jose-Pablo Sanchez-Rodriguez ◽

Alejandro Aceves-Lopez

Keyword(s):

Unmanned Aerial Vehicles ◽

Stereo Vision ◽

Autonomous Navigation ◽

Three Dimensional ◽

Field Of View ◽

Line Of Sight ◽

Onboard Computer ◽

Low Weight ◽

Vision Based Navigation ◽

Difficult Challenge

SUMMARYThis paper presents an overview of the most recent vision-based multi-rotor micro unmanned aerial vehicles (MUAVs) intended for autonomous navigation using a stereoscopic camera. Drone operation is difficult because pilots need the expertise to fly the drones. Pilots have a limited field of view, and unfortunate situations, such as loss of line of sight or collision with objects such as wires and branches, can happen. Autonomous navigation is an even more difficult challenge than remote control navigation because the drones must make decisions on their own in real time and simultaneously build maps of their surroundings if none is available. Moreover, MUAVs are limited in terms of useful payload capability and energy consumption. Therefore, a drone must be equipped with small sensors, and it must carry low weight. In addition, a drone requires a sufficiently powerful onboard computer so that it can understand its surroundings and navigate accordingly to achieve its goal safely. A stereoscopic camera is considered a suitable sensor because of its three-dimensional (3D) capabilities. Hence, a drone can perform vision-based navigation through object recognition and self-localise inside a map if one is available; otherwise, its autonomous navigation creates a simultaneous localisation and mapping problem.

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Abstract TP245: Feasibility of Mobile, Wearable Telestroke Devices

Stroke ◽

10.1161/str.47.suppl_1.tp245 ◽

2016 ◽

Vol 47 (suppl_1) ◽

Author(s):

Steven Warach ◽

Ben T King ◽

Kristen V Chandler ◽

Christopher Topel ◽

Irene A Tabas ◽

...

Keyword(s):

Visual Field ◽

Field Testing ◽

Field Of View ◽

Visual Field Testing ◽

Glass Technology ◽

Technical Problems ◽

Smart Glasses ◽

Patient Interaction ◽

Video And Audio ◽

Strongly Agree

Background: Wearable technologies offer potential telestroke applications that are more mobile and potentially less expensive than traditional telemedicine carts. In an earlier, pilot phase of this research program the best performing software and hardware combination for transmission of encrypted video and audio streaming was selected for further testing. Method: We tested Vuzix M100 smart glasses device and Pristine EyeSight HIPAA-compliant video streaming services. The device wearers, emergency physicians, performed the NIHSS, and a remote vascular neurologist or neurology resident viewed the exam. Providers recorded their score and evaluated the functionality of the device with a standardized list of questions. Results: The device was assessed in 52 subjects. The providers wearing the device reported the device useful (Agree or Strongly Agree) in making an assessment in 79% of cases and that they could assess the patient well 90% of the time. However, the wearers also reported both distraction from and interference with patient interaction due to the device in 98% of cases evaluated. The viewers also reported finding the device useful in making an assessment of stroke symptoms in 79% of cases (a different set of 79% than the wearers), but in only 65% of cases did they Agree or Strongly Agree that they could assess the patient well. Viewers reported an inadequate field of view for visual field testing in 63% of cases. The inter-rater agreement between the wearer and viewer on the total NIHSS showed moderate agreement (κ = 0.45). Although the technology was easy to use in 92% of the assessments, technical problems (mainly connectivity lags) were reported by the wearer 46% of the time and by the viewer 31% of the time. The technology was rated inadequate for assessing patients in 1 case by the wearers and 3 cases by the viewers. Conclusion: Wearable smart glass technology is feasible in assessing stroke patients and shows promise as a telestroke solution, however interference with physician-patient interaction, limited field of view for visual field testing and connectivity glitches are perceived limitations.

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Synthetic Wavelength Holography: Snapshot Non-Line-of-Sight Imaging with High-Resolution and Wide Field of View

10.21203/rs.3.rs-84906/v1 ◽

2020 ◽

Author(s):

Florian Willomitzer ◽

Prasanna Rangarajan ◽

Fengqiang Li ◽

Muralidhar Balaji ◽

Marc Christensen ◽

...

Keyword(s):

High Resolution ◽

Imaging System ◽

Scattered Light ◽

Field Of View ◽

Line Of Sight ◽

Wide Field ◽

Navigation Systems ◽

Small Probe ◽

Wide Field Of View ◽

Non Line Of Sight

Abstract The presence of a scattering medium in the imaging path between an object and an observer is known to severely limit the visual acuity of the imaging system. We present an approach to circumvent the deleterious effects of scattering, by exploiting spectral correlations in scattered wavefronts. Our Synthetic Wavelength Holography (SWH) method is able to recover a holographic representation of hidden targets with high resolution over a wide field of view. The complete object field is recorded in a snapshot-fashion, by monitoring the scattered light return in a small probe area. This unique combination of attributes opens up a plethora of new Non-Line-of-Sight imaging applications ranging from medical imaging and forensics, to early-warning navigation systems and reconnaissance. Adapting the findings of this work to other wave phenomena will help unlock a wider gamut of applications beyond those envisioned in this paper.

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