Reflective polarization volume gratings for high efficiency waveguide-coupling augmented reality displays

Abstract It is a challenge for the dynamic inspection of railway route for freight car transporting cargo that out-of-gauge. One possible way is using the inspection frame installed in the inspection train to simulate the whole procedure for cargo transportation, which costs a lot of manpower and material resources as well as time. To overcome the above problem, this paper proposes an augmented reality (AR) based dynamic inspection method for visualized railway routing of freight car with out-of-gauge. First, the envelope model of the dynamic moving train with out-of-gauge cargo is generated by using the orbital spectrum of the railway, and the envelope model is matched with a piece of homemade calibration equipment located on the position of the railway that needs to be inspected. Then, the structure from motion (SFM) algorithm is used to reconstruct the environment where the virtual envelope model occludes the buildings or equipment along the railway. Finally, the distance function is adopted to calculate the distance between the obstacle and the envelope of the freight car with out-of-gauge, determining whether the freight car can pass a certain line. The experimental results show that the proposed method performs well for the route selection of out-of-gauge cargo transportation with low cost, high precision, and high efficiency. Moreover, the digital data of the environments along the railway and the envelope of the freight car can be reused, which will increase the digitalization and intelligence for route selection of out-of-gauge cargo transportation.

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High efficiency single-mode fibre to Ti:LiNbO3 waveguide coupling

Electronics Letters ◽

10.1049/el:19820022 ◽

1982 ◽

Vol 18 (1) ◽

pp. 30 ◽

Cited By ~ 28

Author(s):

V. Ramaswamy ◽

R.C. Alferness ◽

M. Divino

Keyword(s):

High Efficiency ◽

Single Mode ◽

Single Mode Fibre ◽

Waveguide Coupling ◽

Mode Fibre

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Edge Computing Driven Scene-aware Intelligent Augmented Reality for Manual Assembly

10.21203/rs.3.rs-736006/v1 ◽

2021 ◽

Author(s):

Mingyu Fu ◽

Wei Fang ◽

Shan Gao ◽

Jianhao Hong ◽

Yizhou Chen

Keyword(s):

Augmented Reality ◽

Cognitive Load ◽

High Efficiency ◽

Computing System ◽

Edge Computing ◽

Assembly Process ◽

Manual Assembly ◽

Worker Center ◽

Assembly Operations ◽

Assembly Tasks

Abstract Wearable augmented reality (AR) can superimpose virtual models or annotation on real scenes, and which can be utilized in assembly tasks and resulted in high-efficiency and error-avoided manual operations. Nevertheless, most of existing AR-aided assembly operations are based on the predefined visual instruction step-by-step, lacking scene-aware generation for the assembly assistance. To facilitate a friendly AR-aided assembly process, this paper proposed an Edge Computing driven Scene-aware Intelligent AR Assembly (EC-SIARA) system, and smart and worker-centered assistance is available to provide intuitive visual guidance with less cognitive load. In beginning, the connection between the wearable AR glasses and edge computing system is established, which can alleviate the computation burden for the resource-constraint wearable AR glasses, resulting in a high-efficiency deep learning module for scene awareness during the manual assembly process. And then, based on context understanding of the current assembly status, the corresponding augmented instructions can be triggered accordingly, avoiding the operator’s cognitive load to strictly follow the predefined procedure. Finally, quantitative and qualitative experiments are carried out to evaluate the EC-SIARA system, and experimental results show that the proposed method can realize a worker-center AR assembly process, which can improve the assembly efficiency and reduce the occurrence of assembly errors effectively.

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High-efficiency Vertical Fiber-to-Polymer waveguide Coupling scheme for scalable polymer photonic circuit

Optics Express ◽

10.1364/oe.412266 ◽

2021 ◽

Author(s):

Siddharth Nambiar ◽

Abhai Kumar ◽

Rakshitha Kallega ◽

Praveen Ranganath ◽

Priya e ◽

...

Keyword(s):

High Efficiency ◽

Coupling Scheme ◽

Polymer Waveguide ◽

Waveguide Coupling ◽

Photonic Circuit

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Augmented bricklaying

Construction Robotics ◽

10.1007/s41693-020-00035-8 ◽

2020 ◽

Vol 4 (3-4) ◽

pp. 151-161

Author(s):

Daniela Mitterberger ◽

Kathrin Dörfler ◽

Timothy Sandy ◽

Foteini Salveridou ◽

Marco Hutter ◽

...

Keyword(s):

Augmented Reality ◽

High Efficiency ◽

Digital Fabrication ◽

3D Registration ◽

Augmented Reality System ◽

Robotic Fabrication ◽

Assembly Method ◽

Human Computer Interfaces ◽

Machine Communication ◽

Building Project

AbstractAugmented bricklaying explores the manual construction of intricate brickwork through visual augmentation, and applies and validates the concept in a real-scale building project—a fair-faced brickwork facade for a winery in Greece. As shown in previous research, robotic systems have proven to be very suitable to achieve various differentiated brickwork designs with high efficiency but show certain limitations, for example, in regard to spatial freedom or the usage of mortar on site. Hence, this research aims to show that through the use of a craft-specific augmented reality system, the same geometric complexity and precision seen in robotic fabrication can be achieved with an augmented manual process. Towards this aim, a custom-built augmented reality system for in situ construction was established. This process allows bricklayers to not depend on physical templates, and it enables enhanced spatial freedom, preserving and capitalizing on the bricklayer’s craft of mortar handling. In extension to conventional holographic representations seen in current augmented reality fabrication processes that have limited context-awareness and insufficient geometric feedback capabilities, this system is based on an object-based visual–inertial tracking method to achieve dynamic optical guidance for bricklayers with real-time tracking and highly precise 3D registration features in on-site conditions. By integrating findings from the field of human–computer interfaces and human–machine communication, this research establishes, explores, and validates a human–computer interactive fabrication system, in which explicit machine operations and implicit craftsmanship knowledge are combined. In addition to the overall concept, the method of implementation, and the description of the project application, this paper also quantifies process parameters of the applied augmented reality assembly method concerning building accuracy and assembly speed. In the outlook, this paper aims to outline future directions and potential application areas of object-aware augmented reality systems and their implications for architecture and digital fabrication.

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High-efficiency broadband light coupling between optical fibers and photonic integrated circuits

Nanophotonics ◽

10.1515/nanoph-2018-0075 ◽

2018 ◽

Vol 7 (12) ◽

pp. 1845-1864 ◽

Cited By ~ 26

Author(s):

Gyeongho Son ◽

Seungjun Han ◽

Jongwoo Park ◽

Kyungmok Kwon ◽

Kyoungsik Yu

Keyword(s):

Integrated Circuits ◽

Optical Fibers ◽

Optical Switching ◽

High Efficiency ◽

Photonic Integrated Circuits ◽

Coupling Efficiency ◽

Optical Signal ◽

Coupling Methods ◽

Light Coupling ◽

Waveguide Coupling

AbstractEfficient light energy transfer between optical waveguides has been a critical issue in various areas of photonics and optoelectronics. Especially, the light coupling between optical fibers and integrated waveguide structures provides essential input-output interfaces for photonic integrated circuits (PICs) and plays a crucial role in reliable optical signal transport for a number of applications, such as optical interconnects, optical switching, and integrated quantum optics. Significant efforts have been made to improve light coupling properties, including coupling efficiency, bandwidth, polarization dependence, alignment tolerance, as well as packing density. In this review article, we survey three major light coupling methods between optical fibers and integrated waveguides: end-fire coupling, diffraction grating-based coupling, and adiabatic coupling. Although these waveguide coupling methods are different in terms of their operating principles and physical implementations, they have gradually adopted various nanophotonic structures and techniques to improve the light coupling properties as our understanding to the behavior of light and nano-fabrication technology advances. We compare the pros and cons of each light coupling method and provide an overview of the recent developments in waveguide coupling between optical fibers and integrated photonic circuits.

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