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Purpose: This study describes a prototype developed for aphakia without capsular support (AWCS) and its proof of concept. Methods: This descriptive study used a 3D software to create and analyze virtual prototypes before manufacturing. A nylon-6/nylon-6.6 copolymer filament and a 3D printer were used for prototyping. A device implantation technique was developed using a 23-gauge hypodermic needle. Two opposing markings, 2 mm posterior to the limbus, were made to determine the location of the scleral punctures and the final position of the device. After adequate centralization and positioning of the device, its haptics were cut and cauterized to generate thermal modeling of the extremity and allow the thickening of the tips (flange), serving as an anchoring mechanism to the sclera. The efficacy and adequacy of the technique and device were then evaluated. Results: Vitreous tissue extrusion was not observed during the sclerotomy. The device was well fixed to the sclera; however, adequate IOL stability and centralization still needed to be achieved. The surgeon evaluated the adequacy of all the other devices' characteristics. Conclusions: The development of a technology prototype for correcting AWCS was possible. Although the proposed prototype met most of the established concept guidelines, the stability of the IOL position remains challenging. [ABSTRACT FROM AUTHOR]

The effect of the hydraulic anti-kink system on the longitudinal-yaw stability and small radius curve passing safety of the four-module single-type tram is studied. Firstly, the dynamics model of the anti-kink system is established based on the working principle of the anti-kink system, and the dynamic response of the system is analysed. Secondly, the influence of the anti-kink system on the longitudinal-yaw stability is analysed based on the longitudinal-yaw dynamics model of the four-module single-type tram. Finally, a virtual prototype of the anti-kink system and the four-module single-type low-floor tram with independent rotating wheels is established to test the longitudinal-yaw stability of the vehicle, and the curve passing safety. The results show that: the double-hinged device increases the longitudinal-yaw instability of the vehicle and is more likely to produce jackknifing phenomenon, so the stiffness of the anti-kink system should be set as much as possible to prevent the jackknifing phenomenon and ensure the safe operation of the train. By reducing the stiffness of the anti-kink system properly, the wheel-rail force during curve passing can be reduced, and thus improving vehicle safety. [ABSTRACT FROM AUTHOR]

This paper emphasises the study of switched nonlinear cyber-physical systems (CPSs) subjected to input delay, actuator faults and deception attacks by a $ H_\infty $ H ∞ -based truncated predictive control design. Particularly, the predictive controller uses delayed state information in addition to the traditional feedback control to estimate the present state for the feedback. Furthermore, the proposed control design is modelled with a truncated predictive approach which is also used to compensate the effects of actuator faults and attacks that also satisfy a predefined $ H_\infty $ H ∞ index simultaneously. With the assistance of the Lyapunov stability theory, a novel set of adequate criteria are acquired in terms of LMIs which assure the asymptotical stability of the switched nonlinear CPS under prescribed predefined $ H_\infty $ H ∞ performance levels. Eventually, the proposed theoretical results are validated through two numerical examples. [ABSTRACT FROM AUTHOR]

This research investigated the potential of a short industry-facilitated masterclass in virtual product development to inform future curriculum development and teaching and learning approaches within the context of Higher Education. An action research approach was adopted with fashion business student participants (n = 22). A pre-class survey, field notes, discussions, and reflections during the four-day masterclass provided data for the study. This study actively engaged student participants to inform curriculum development to advance the digital transformation of the industry. The fashion business students reported the experience as helpful to understand the potential of 3D or 'virtual' technologies within more sustainable product development processes, and to understand their roles as fashion marketing and/or management professionals within the emerging Design/Present/Sell/Produce-model. This study contributes to the literature on how to advance digital skills in higher education. [ABSTRACT FROM AUTHOR]

The ambiguity of online text communication coming from the lack of audiences' social cues often causes misunderstanding, which arouses a negative image of the message sender. Likewise, message senders feel social anxiety about whether their intentions are properly conveyed, or whether their messages may not sound offensive or impolite in communicating with text such as writing a self-introduction letter. In this paper, we design and develop a messaging assistant (Emoware) prototype which visualizes the audience's predicted emotions to motivate the message sender to reveal more information. We conducted a user study comparing Emoware to plain text interface with 56 participants and found that Emoware positively affects writing by improving users' self-disclosure intention, social support, and self-disclosure. This study contributes to overcoming the limitations of text modality in online communication. [ABSTRACT FROM AUTHOR]

Presented in the paper is a virtual commissioning methodology for the design and verification of an OHT (Overhead Hoist Transporter), which is a vehicle that travels on the overhead track in a FAB (Factory for making semiconductor chips), and directly accesses the load port of the stocker or process equipment by the belt driven hoisting mechanism. Since the material flows of a FAB is extremely complicated, it is important to design the OHT control software by considering various situations. The proposed virtual commissioning methodology supports the full verification of the OHT control software by performing the simulation involving a 'virtual OHT model' and a 'real OHT controller'. We separate the virtual OHT model into two parts, a physical model (mechanical part) and a logical model (electrical part) to achieve the concurrency of mechanical and electrical designs of an OHT. Virtual commissioning identifies and addresses design flaws and operational faults so that significant savings can be achieved. The prototype of the proposed virtual commissioning methodology has been implemented and tested with several examples. [ABSTRACT FROM AUTHOR]

An optimization strategy integrating contribution analysis, design of experiment, an approximate model and a preference selection index (PSI) method is proposed to establish an efficient multi-objective lightweight design approach for heavy commercial vehicle frames. First, finite element and rigid–flexible coupling virtual prototype models are established and their accuracy is verified using experiments. Secondly, the fatigue life of the frame is calculated using the power spectral density function, frequency response function and corrected stress–life curve. Finally, the thicknesses of frame components are regarded as design variables, and the mass and maximum root mean square stress are considered as design objectives in the process of lightweight design. Three optimization strategies are used to investigate the characteristics of the PSI method. The results showed that the optimization strategy combined with the PSI method demonstrates high computational efficiency and reliability. [ABSTRACT FROM AUTHOR]

Distributed economic dispatch system has gained a lot of attention because it has better robustness, faster computation and less communication burden, but the system stability in the presence of communication delay is still researched at the fundamental level. By introducing the concept of virtual distributed generation, this paper develops a fully version of the distributed economic dispatching strategy for an active distribution network, and establishes the stability analysis model of the distribution network considering symmetric and asymmetric communication time-delay. The Lyapunov stability theorem and the free weight matrix method are comprehensively applied to derive the time-delay stability criterion of the system and solve the delay stability margin with a lower conservativeness. The distributed economic dispatch strategy in this paper under various operating conditions, the delay stability analysis method and delay stability margin solution are verified by the simulation results on an active distribution network modified based on the IEEE-14 system. [ABSTRACT FROM AUTHOR]

The finite element three-dimensional transient model of the annealing process, including conductive and convective heat transfer in an aluminum (Al) coil was developed, implemented, and validated. It combines winding force dependent effective radial thermal conductivity model and the novel convective heat transfer modeling methodology. Experimental validation of the finite element model was performed for two industrial coils having different dimensions, strip thickness and crowning depth. The general agreement between the predicted and measured temperatures for most of the probes was better than 10% at the target material temperature. A series of measurements were configured and performed to supply both the input and validation data for the simulations. The effect of the additional wetted area on the convective heat transfer at the coil base was quantified. The guidelines on the virtual prototyping of the Al coil annealing process were provided, which can be of interest for the process designers. [ABSTRACT FROM AUTHOR]

The benefits of employing the virtual simulation tools tend to be amplified when applied at the initial stages of the project. In order to predict the loads acting on a component, a load generation methodology is used. The suspension loads generated depend on a series of suspension and body characteristics. These characteristics are refined to suit ride, handling and fuel consumption targets. The focus of the present study is to evaluate the effects of these variations on the rear suspension durability using load generation DOE and Fatigue analyses. Through this understanding, an initial virtual prototype can be idealized. [ABSTRACT FROM AUTHOR]

The anisotropic behavior of oil palm fibers (OPF) was investigated using finite element models, which were used to fit experimental data from stalk and mesocarp oil palm fibers under different tensile deformation modes. The experimental results showed damage to oil palm fibers due to deformation, viscoelastic behavior from reduced stress at fixed strain, as well as anisotropic behavior from tensile-twisting tests. In this work, the finite element models were improved from the previous works on the fiber mechanics by including Fung orthotropic and Prony series viscoelastic functions. The developed single-element finite element model agreed with experimental tensile data under cyclic, stress-relaxation, and step-relaxation modes. The modeling parameters from the single element model and information from the experimental work were then used to simulate the deformation of a virtual fiber obtained from µ-CT analysis, as well as its composite model. [ABSTRACT FROM AUTHOR]

Virtual Prototyping is a robust method to greatly reduce the labour cost and time required of the vehicle prototype. Still, the absence of the haptic sensory channel degrades the immersive experience evaluation, especially in terms of in-vehicle human-machine interaction (HMI). Hence, this study proposed a modular visuo-haptic mixed reality (VHMR) aided prototype technique suitable for in-vehicle HMI evaluations, which positions itself between pure VR technology and physical object assessment. Technology acceptance model (TAM) was also introduced to empirically investigate the perceived usefulness, ease of use, presence, risk, as well as the behavioural intention of the prototype technique separately. Results revealed that the modular visuo-physical object prototype technique has certain advantages in terms of positioning, usability and user acceptance among the VHMR solutions, and could be adopted as a low-fidelity prototype to build common ground in the R&D team and get quick feedback from users for the agile in-vehicle HMI development. [ABSTRACT FROM AUTHOR]

Swirling-flow nanobubble generator is an efficient hydrodynamic cavitation method that can continuously produce enormous quantities of bulk nanobubbles. However, the development of hydrodynamic models of nanobubble generation remains challenging and is rarely found in the literature due to the associated modeling complexity. In this work, a hydrodynamic model was developed to predict bubble size distribution in a swirling-flow type nanobubble generator using a combination of computational fluid dynamics (CFD) and population balance method (PBM). The proposed model was evaluated by considering several combinations of bubble coalescence, breakage, and turbulence models. The results show that the combination of the turbulence coalescence and Luo breakage models predicted better than any other model combination. The selection of appropriate turbulence models could improve the modeling accuracy. The standard k-Ω model provided better predictions than other turbulence models for high flow rates, while the standard k-ε model was more appropriate for low flow rates. The bubble number density was successfully predicted for a 30 min generation time. The turbulence dissipation rate influenced the bubble number density and mass transfer, and the results of simulation considering this relation corresponded to the experimental results. Therefore, the coupled CFD-PBM model can aid in the design of nanobubble generators using virtual prototypes and reduce the development costs required for broader applications. [ABSTRACT FROM AUTHOR]

In India, the cashew nut shelling (CNS) is an important task in all small-scale cashew nut processing industries. Workers engaged in CNS task commonly operate pedal-operated cashew nut sheller (CNSR) in awkward standing posture that can contribute to work-related musculoskeletal disorders (MSDs). However, investigations from an ergonomics perspective have barely been conducted in Indian small-scale cashew nut processing industries. Therefore, the present study aims to evaluate the postural workload in CNS task to propose an ergonomic design intervention in small-scale cashew nut processing industries. A combination of methods, including posture recording, postural assessment, interviews, questionnaire study, virtual prototyping, and digital human modeling and simulation, were used. Using the pedal-operated CNSR resulted in high-risk postures of MSDs. Based on these preliminary findings, a simple, improved, and adjustable hand-operated CNSR was designed and evaluated ergonomically. It was found that newly designed CNSR improved postures noticeably and provided comfort for workers. [ABSTRACT FROM AUTHOR]

Increasing demands for full-glazed façades have motivated designers/researchers to propose advanced control strategies for dynamic shading systems to mitigate the negative impacts of excessive sunlight penetration into interior spaces. Nevertheless, in line with the latter, outside view is commonly obstructed as a result of utilizing conventional shading systems including Venetian blinds. This is primarily the consequence of conventional systems' lack of flexibility to respond appropriately to occupants' requirements and the sun's changing orientation. This paper presents the virtual prototype development of a Multi-layer blind system through a brute-force algorithm. It emphasizes proposing a customizable and affordable complex shading system with advanced control strategies for multiple building typologies. The research intends to improve visual comfort (daylight and glare) and maximize unblocked window view in a single office room located in Tehran. Furthermore, the control system was developed based on a combination of the cut-off and a glare protection control strategy. Concerning the cut-off control system, the slat angles change to block direct sun radiations, and then, if needed, the position of the front slat, named 'View slat', changes to avoid discomforting glare. In conclusion, the proposed prototype could improve daylight performance by up to 44% and maximize unobstructed outdoor view by approximately 47% in an almost glare-free zone. Finally, the usage of swarm intelligence could significantly improve the performance of the proposed prototype by determining which blind and how they should respond to environmental changes and occupants' requirements. Abbreviations: AFs: Adaptive Façades; OF: Openness Factor; OCF: Openness Curvature Factor; MLBS: Multi-layer Blind System; RML: Relative Maximum Luminance; GRV: Glare Response Vote; DA: Daylight Autonomy; Ev: Vertical eye illuminance; sDA: Spatial Daylight Autonomy; WPI: Work-plane Illuminance; DF: Daylight Factor; WFR: Window-to-Floor area Ratio; DGP: Discomfort Glare Probability; DGI: Discomfort Glare Index; UDI: Useful Daylight Illuminance; WPI: Work-plane Illuminance; GSV: Glare Sensation Vote; IV: A numerical score of the interest of a scene, assessed by a group of subjects; DGPs: Daylight Glare Probability simplified; cDA: Continuous Daylight autonomy; PGSV: Predicted Glare Sensation Vote; UDI_a: Useful Daylight Illuminance achieved; GSVs: Glare Sensation Votes [ABSTRACT FROM AUTHOR]

Systems are being developed for power distribution on future navy ships to effectively incorporate advanced electrical systems requiring DC power. These islanded DC microgrids provide new challenges to the management of power flow throughout the system, and thus require advanced controls to accurately regulate and stabilise the systems during changing operational conditions. Therefore, adaptive droop control is proposed as a power management layer for these maritime DC microgrids. This paper reports on a method that uses adaptation of the controller parameters to account for uncertainty and changes in the system in order to accurately regulate the power sharing among distributed generation sources and to stabilise the bus voltage of the system. The proposed method is applied to a virtual prototype of a medium voltage direct current (MVDC) ship power system and demonstrated through notional operational scenarios to test the effectiveness of the control algorithm utilising controller hardware in the loop (CHIL) experimentation. [ABSTRACT FROM AUTHOR]

Product design becomes more than just dealing with pieces of hardware, but rather is realised through co-design of an entire product ecosystem, involving coordinated product fulfilment, services, experiences and human satisfaction at the individual and the community levels (Jiao et al. [4]). I Design education i , including design education and pedagogy in engineering; design thinking and design doing; complex sociotechnical systems; public policy design; design engineering epistemologies; design learning mechanisms and learning systems; design ethics; design diversity, equity and inclusivity; as well as design education assessment methods, instruments, and metrics. I Design of product realisation systems i with focus on planning, optimisation, control and management of processes, fulfilment and systems, including systems design and design complexity; integrated engineering design development; manufacturing systems design; design for changeable and reconfigurable production systems; supply chain design; design for logistics; operations engineering design; service delivery system design; integrated product and process development; global and distributed engineering design; and multi/inter/trans-disciplinary engineering design. The subject matter of design has traditionally been focused on design of engineered (e.g., physical/mechanical) products. [Extracted from the article]

This study was undertaken to develop a new index, the Main Landing Gear Cumulative Stroke (MLGCS) index, to evaluate airport runway roughness. Using ADAMS/Aircraft software, we first developed and validated a virtual prototype model of the Boeing B737-800 aircraft and then employed the model to predict the aircraft's dynamic responses with regard to roughness. Using this prototype model and comparing it to the International Roughness Index (IRI) that is designed to evaluate roadway roughness, we established a landing gear cumulative stroke (LGCS) model to represent runway roughness. The results show that taxiing speed is an important factor using the LGCS model. According to the most unfavorable scenario, we determined the LGCS of the nose landing gear to be 100 km/h and that of the main landing gear to be 60 km/h. These results underscore that, based on correlation analysis, using the cumulative stroke of the main landing gear is more reasonable than using that of the nose landing gear to evaluate runway roughness. Furthermore, based on measured data for 37 runways, a comparison of commonly used roughness indices indicates that the MLGCS index proposed in this paper is superior to both the Boeing Bump Index and the IRI. [ABSTRACT FROM AUTHOR]

This paper investigates virtual reality head-mounted displays (VR-HMDs) as immersive and interactive media to simulate how new automotive user interfaces will contribute to passengers' user experience (UX) through experience prototyping of a conceptual infotainment system for front-seat passengers. It first demonstrates the integration of VR-HMDs into experience prototypes through (1) identification of what to prototype by deconstructing the system into its aspects; (2) definition of the scope and fidelity of the prototype for each design aspect; and (3) elimination of challenges brought by VR-HMD (e.g. simulation sickness) through strategies like static presentation of car surroundings. Secondly, it confirms the strategies to exploit immersion safely with the results of the simulation sickness and presence questionnaires. Thirdly, it probes how using VR-HMD affects UX appraisals with content analysis of the follow-up interviews. The paper concludes with a discussion of how VR-HMDs enrich digital appraisals of (automotive) user interfaces at early design stages. [ABSTRACT FROM AUTHOR]

Skid-resistance performance of a runway greatly influences aircraft landing safety. A wet runway significantly increases the incidence rates of aircraft overrun. To study the influence of the skid-resistance performance of a runway on aircraft landing, a co-simulation method is proposed. First, a finite element (FE) model of the local tire-water film-runway simulation is established to obtain the combination coefficient-slip ratio curve of a tire on a wet runway. Second, a global model of an Airbus A320 virtual prototype (VP) is created. Then, on the basis of fuzzy control theory, a two-dimensional (2D) fuzzy controller of the aircraft AB is established. The friction coefficient-slip ratio curve of the tire on the wet runway obtained in the local simulation is introduced into the full-scale hydroplaning simulation model of the aircraft. Finally, the global-local multiscale simulation method is used to analyze the skid-resistance behaviour of the aircraft on three types of runways. It is found that the increase of water film thickness of the pavement and the increase of the grounding speed cause the attenuation of the friction coefficient of a runway, finally causing the reduction of the deceleration rate of the aircraft and the increase of the braking distance. [ABSTRACT FROM AUTHOR]

Using dynamic load identification technology to identify the wheel-rail force of rail vehicles is an economical and convenient method for indirect measurement. In this paper an analytical load identification method is proposed. Firstly, based on the theory of structural dynamics, the Duhamel integral is applied, combined with the characteristics of the rail vehicle system, to derive the analytical load identification method. Secondly, the correctness of the method is verified by a multi-degree-of-freedom system with exact solution. Next, a detailed vehicle dynamics simulation model is established as a virtual test vehicle and source of virtual measurements of the vehicle responses (axlebox accelerations). Different operating conditions are considered, and the virtual acceleration measurements are used as input to the load identification method for indirect measurement of the wheel-rail forces. Finally, the identified vertical and lateral wheelset force, vertical force of the left and right wheels, derailment coefficient and wheel unloading rate are compared with the corresponding time-histories from the virtual test-vehicle simulations. A good agreement is found with all of their correlation coefficients above 0.8. This result has important implications on the safety evaluation of vehicle curve negotiation by using acceleration measurements only, without the need for direct force measurements. [ABSTRACT FROM AUTHOR]

This study examines how virtual pattern-making training enhances older adults' spatial visualisation ability, depending on their ethnic background. Following receipt of IRB approval, a total of 600 female older adults were recruited to the study. To assess participants' current spatial visualisation ability, a letter rotation test was employed both pre-test and post-test. A virtual pattern-making training video was developed using a virtual prototyping programme, Browzwear VStitcher. The training video explained the basic concept of virtual pattern-making with examples, and participants were then asked to watch the video between pre-test and post-test. The results of the two tests were compared using a paired sample t-test. The results found that, of the four ethnic groups, African American showed a significant improvement in letter rotation scores after the training. The findings of this study will contribute to the knowledge and understanding of virtual pattern-making in relation to older adults' cognitive skills. [ABSTRACT FROM AUTHOR]

Inefficiency in real-time visualization and user interaction in traditional accident causation models (ACMs) necessitates the development of a dynamic ACM that can foster real-time hazard identification, accident prevention and interactive safety training. A virtual reality-based accident causation model (VR-ACM) may serve such a purpose. In this study, we performed a comprehensive literature review on different ACMs and safety training practices. The limitations of the existing models and practices are identified. A VR-ACM model is proposed comprising three modules: VR-based modelling and simulation, accident causation and safety training. Several research issues for VR-ACM are highlighted. An experimental study with 22 crane operators is presented, showing the applicability of the proposed model. The proposed VR-ACM serves as a medium for analysis of potential underlying causes of accidents, the three-dimensional perspective of visual analysis, real-time user interactions and real-time judgement and decision-making. [ABSTRACT FROM AUTHOR]

In order to study the complex dynamic characteristics of hydro-mechanical CVT (hydro-mechanical continuously variable transmission), the gearbox machine dynamics simulation model based on AMESim was established for the most important of confluent planetary gear mechanism in the gearbox. Creo2.0 was used to draw 3D virtual prototype, and according to the actual movement of the link, added the corresponding constraints to get the planetary dynamics simulation model based on the multi-body dynamics simulation software ADAMS. Based on the classical formula of gear meshing force, the theoretical values of meshing force of planetary gear were calculated, and the dynamics analysis of planetary gear was carried out by using ADAMS. The simulation results were basically consistent with the theoretical values. It researched the influence of the speed regulation process on planetary gear engagement impact under the three case: speed regulation rate and speed direction, speed regulation under different load levels and different engine speed. The speed regulation under speed regulation rate and different load levels had obvious impact on planetary gear meshing force, the impact degree increased with the increasing of speed regulation rate and load; this work has good engineering and application value, and provides the reference for the structure optimization and adjustment. [ABSTRACT FROM AUTHOR]

The purpose of this article is to discuss how to improve the ways the Taiwanese Ground Forces use the common operational picture (COP) for training to improve the efficacy of tactical training and understanding of the combat field. Augmented Reality (AR) has made huge progress in the past decade and is widely applied in education, industrial sector, medical industry, military industry. More attention is focused on training simulations for soldiers and improving battlefield perception systems. The application of AR in tactical training is still an emerging realm of research but has a huge potential. Related studies have shown the application and technical limitations of AR technology in the military field. Then, using a user-oriented research method, a tactical training system based on 3D augmented reality is proposed and constructs a system prototype to combine virtual information with the real environment and provide the advantages of intuition, interaction, and information visualization. The experiment had an experimental group and control group, and an independent sample "t" was tested for evaluation and comparison. The experimental results show that the understanding of battlefield situations and tactical actions in the AR-based tactical teaching system has changed significantly. The system prototype and experimental content provide useful contributions to the tactical teaching of the Army Academy, and it can be used as a reference for the development of AR in future military applications. [ABSTRACT FROM AUTHOR]

Urban stormwater systems consist of structural characteristics including topological structure, pipe capacity, low impact developments and storage tanks, and these characteristics are important in the planning and the retrofitting stage. Therefore, this study evaluates the cost-effectiveness of each structural characteristic for enhancing resilience, based on simulation of massive virtual stormwater systems. The results show that it is more cost-effective to enhance resilience by finding better topological structure. Enlarging pipe capacity is also a fairly good choice, since it is more effective than building storage tanks, and more economical than building low impact development. Further, we find that improving topological structure and enlarging pipe capacity have potential in bringing extra resilience in the retrofitting stage for building low impact development and storage tanks. Therefore, the planning stage of urban stormwater systems should be considered seriously. Furthermore, we should pay more attention to the topological structure of urban stormwater systems. [ABSTRACT FROM AUTHOR]

This document discusses the development of digital twin (DT) technologies and their application in the field of vehicle system dynamics. It explains that digital twin technologies are closely related to concepts such as Industry 4.0, IoT, and Big Data, and have become increasingly important in engineering tasks such as design optimization and predictive maintenance. The document emphasizes the need to understand the transition from virtual prototyping to digital twin methodologies, as well as the combination of vehicle dynamics modeling and data-based approaches in vehicle engineering applications. It also highlights that more research is needed in this area to improve the system architecture and developmental framework of digital twin techniques. The document concludes by inviting researchers to contribute further innovations and research papers on digital twins in Vehicle System Dynamics. [Extracted from the article]

Virtual reality (VR) technology offers great potential for design collaboration by enabling designers to enhance the collaborative exploration process. However, few studies have provided practical insights into the use of VR-based collaboration environment (VRCE) in the field of fashion design. Therefore, this study explored the main features of VRCE solutions currently available and classified their major types in order to develop a deeper contextual understanding of the use of VRCE for fashion design collaboration. The VRCE solutions were collected from various media channels and finally classified into three representative types: virtual meeting and design planning, three-dimensional virtual prototyping, and design review. Consequently, the findings emphasised that the VRCE is useful for general design collaboration. Yet, to more efficiently process the use of domain-specific information and design process required for collaborative exploration of the fashion design concept development, additional technology functions that integrate with the fashion design process should be developed. [ABSTRACT FROM AUTHOR]

Clearance joints and variable load have a great influence on the dynamic performance of shift manipulator for robot driver. In this article, a dynamics model of clearance joint and a simulation method of variable load are proposed to analyze the influence of clearance joint and variable load on the dynamic performance of shift manipulator. Firstly, a hybrid nonlinear contact force model is established to describe the normal contact force of revolute clearance joint, and a modified Coulomb friction model is used to describe the tangential contact force of revolute clearance joint. On this basis, a virtual prototype dynamics model of shift manipulator with multiple revolute clearance joints is established. Then a power transmission model of shift manipulator including the variable load model at the end of shift manipulator is established. The time-varying and nonlinear characteristics of the load in gear engaging direction are simulated by neural network. Finally, the influences of different clearance dimension and variable load on the dynamic performance of shift manipulator are analyzed. Experiment and simulation results show the validity of the presented analysis, which provides a basis for further structure optimization of shift manipulator. [ABSTRACT FROM AUTHOR]

This paper presents an experimental validation of, phase-lock loop less modified control strategy for single-phase shunt active power filter (APF) to compensate current harmonics and reactive power in single-phase distribution system under distorted supply voltage. The control technique is divided into two parts: first associated with selected frequency signal extraction by using Hilbert transform-based adaptive tuned filter from distorted supply voltage followed by reference current signal generation using DC-link energy balance method. Second deals with an improved pulse width modulation technique which reduces switching ripple and switching frequency for voltage source inverter used as a shunt APF. The overall control scheme is simulated using MATLAB/Simulink environment in the steady state and transient condition of the load. A detailed hardware design and other parameters of proposed system have been presented. A laboratory prototype has been developed using dSPACE DS1104 controller card having TMS320F240 as a slave DSP to verify the simulation results. Simulated and experimental results show that the proposed control technique gives a flexible and fast dynamic response in single-phase distribution system. The harmonic spectral performance of the proposed technique is as per the recommendation of IEEE-519 standards. [ABSTRACT FROM AUTHOR]

Shelters for the displaced can suffer from socio-cultural incompatibility and significant levels of occupant dissatisfaction. Participatory design (PD) is known to help reduce such issues. This is the first study to investigate the effectiveness of different PD methods at engaging and capturing users' needs for shelter design in refugee camps. It also aimed to identify which visualization tools are best at: engaging participants; communicating designs (e.g. concept, size and materials); and facilitating proposing modifications. This is a particularly large study with 16 workshops and 161 participants. Two PD methods were deployed: (i) design-your-own (where refugees proposed their ideal shelter); (ii) adapt-a-design (where refugees evaluated and modified pre-existing shelter designs). The shelters in (ii) were presented using three visualization tools: computer models, physical prototypes and virtual reality. Design-your-own proved less engaging and led participants to produce designs similar to their existing shelters. Adapt-a-design stimulated more dialogue and was more informative. Physical prototypes facilitated engagement in shelter modifications, computer models proved least able to communicate concepts, while virtual reality was best at communicating scale and size. [ABSTRACT FROM AUTHOR]

ABSTRACT—Multiport converters (MPCs) have the tremendous performance over conventional solutions that employ multiple single converters in multi-input and multi-output applications. Further, it gives the economic operation and improves the performance of the system. Hence, in the recent past, a lot of development and research have been carried out for developing the single-input dual-output (SIDO) converters in various aspects which are presented in literature. These topologies have some assumptions made on the charging of inductor current and design of duty cycle for achieving the multiple outputs. In this study, single-input dual-output dc–dc converter is proposed. It independently regulates both the outputs at different voltage levels, and none of the assumptions are made on the basis of inductor charging currents (iL1>iL2 or iL1

The growing complexity in product design and manufacturing processes has made virtual prototyping an important new approach that enhances products and process development. Considering the ergonomic issues evident in product lifecycles, digital human modelling (DHM) is adopted for virtual simulation and proactive evaluation. A motion generation from semantics (MGS) system is proposed in this research. The MGS system features include virtual prototyping, natural language instruction, a method time measurement (MTM) translator and motion generator. The system was implemented using product lifecycle management (PLM) software and validated in an automotive manufacturing company. The practice of intuitively generating manual operations and conducting virtual simulations enables the system planners to quickly respond to manufacturing process changes and recursively improve the tooling and process design flexibility and efficiency. [ABSTRACT FROM PUBLISHER]

The evaluation of visibility factor is an essential activity in the ergonomic analysis and verification process. It influences the product quality and production efficiency significantly. However, manual evaluation of the visibility factor in a virtual prototyping environment is complicated and time-consuming owing to the high complexity of products and manufacturing processes. This paper presents an automatic visibility evaluation method. A view-region model that conforms to the physiological characteristics of field-of-view (FOV) is designed and constructed. The surfaces of the observed-object are discretised into a series of triangular meshes, which function as the evaluation units. A cluster of radial test lines, which represent the rays reflected from each mesh, are generated. The visible types of these meshes are assessed by detecting and analysing these test lines. The authors develop a set of computation models for evaluating various visibility-influencing factors. In addition, the overall quantitative and qualitative visibility evaluation results are provided. A case study is illustrated and the results reveal that this method can evaluate the visibility effectively. Furthermore, the potential visibility-related ergonomic problems can be detected and addressed in advance with the aid of this method. [ABSTRACT FROM AUTHOR]

This study proposes a framework for comparative study on three different positioning solutions for mobile offshore drilling units (MODUs) using high modulus polyethylene (HMPE) ropes, including active mooring with an HMPE rope, conventional dynamic positioning (DP) and active hybrid position-keeping (AHP-K). The goal of the positioning systems is to keep the MODU above the wellhead with acceptable riser-angle loading, minimal energy consumption, reduced underwater noise generation, and harmful emissions. This is the first time a holistic study has been performed on positioning that factors in the financial and environmental costs. The time domain simulation, which includes sea-state, wind, and current profiles, is performed with a well-developed software architecture and control algorithms for MODU position-keeping. The case study addresses a MODU drilling in the Barents Sea. Simulation results show that AHP-K is more efficient compared to the other two positioning solutions for drilling operations in the studied environment. [ABSTRACT FROM AUTHOR]

Modern winch systems have become increasingly complex with hybrid power systems, intelligent control systems, and lightweight synthetic cables with complicated traction and handling mechanisms. During the early design phase, it is hard to manage a large set of parameters for system design exploration and optimisation by traditional trial-and-error approaches. Virtual prototyping provides the users with numerous risk-free possibilities to evaluate the design trade-offs and immediately know the results of any modification. This requires flexible, effective modelling of the dynamic system and efficient handling of the simulation. This paper presents the implementation of a virtual winch prototyping tool for maritime winch design and operations. Model development and setups for co-simulation are described based on an active heave compensated winch with secondary control. Simulation management and user interface are implemented based on web technology and connected to the functional mock-up units as clients through the WebSocket protocol. [ABSTRACT FROM AUTHOR]

Three-dimensional (3D) virtual prototyping and problem-solving have been becoming increasingly important for apparel design students entering the industry. Repeated use of 3D virtual prototypes in computer-aided design (CAD) patternmaking can improve students' interaction skills with the software. Furthermore, it can develop their 3D visualisation and problem-solving skills. The present study examined students' use of 3D virtual prototypes in three consecutive projects. The sequence and content of the projects steered student learning and skill development when using 3D simulations. Findings confirmed that interaction, imagining, and problem-solving skills significantly increased between the first and the last projects. Especially working in pairs had a significant positive impact on students' patternmaking problem-solving abilities and skills as demonstrated in creating 3D simulations. Implications of this study can be used to inform practices when teaching apparel CAD patternmaking and introducing projects with 3D in both academia and industry. [ABSTRACT FROM AUTHOR]

Students in secondary education strive hard enough to understand basic programming concepts. With all that is known regarding the benefits of programming, little is the published evidence showing how high school students can learn basic programming concepts following innovative instructional formats correctly with the respect to gain/enhance their computational thinking skills. This distinction has caused lack of their motivation and interest in Computer Science courses. This case study presents the opinions of twenty-eight (n = 28) high school students who participated voluntarily in a 3D-game-like environment created in Second Life. This environment was combined with the 2D programming environment of Scratch4SL for the implementation of programming concepts (i.e. sequence and concurrent programming commands) in a blended instructional format. An instructional framework based on Papert's theory of Constructionism to assist students how to coordinate or manage better the learning material in collaborative practice-based learning activities is also proposed. By conducting a mixed-method research, before and after finishing several learning tasks, students’ participation in focus group (qualitative data) and their motivation based on their experiences (quantitative data) are measured. Findings indicated that an instructional design framework based on Constructionism for acquiring or empowering students’ social, cognitive, higher order and computational thinking skills is meaningful. Educational implications and recommendations for future research are also discussed. [ABSTRACT FROM PUBLISHER]

Large capacity shovels are deployed in surface mining operations for achieving economic bulk production targets. These shovels use crawler tracks for effective terrain engagement in these environments. Shovel reliability, maintainability, availability and efficiency depend on the service life of the crawler tracks. In rugged and challenging terrains, crawler wear, tear, cracks and failure are extensive resulting in prolonged downtimes with severe economic implications. In particular, crawler shoe wear, tear, cracks and fatigue failures can be expensive in terms of maintenance costs and production losses. No fundamental research has been undertaken to understand the crawler-formation interactions in challenging and rugged terrains in surface mining operations. This study forms the foundations for providing long-term solutions to crawler failure problems. The kinematic equations governing the crawler-formation interactions have been formulated to characterise the crawler motions during shovel production. These equations capture the motions governing the link pin joint, oil sand terrain joint and driving constraints based on the multi-body rigid theory. Crawler propel is achieved by using prescribed velocities along a translational degree of freedom (DOF) and a translational and rotational DOF. The crawler kinematic solutions show that the 3-D crawler–terrain model results in 132 DOFs and requires dynamic modelling to obtain the unknown degrees of freedom. A 3-D virtual prototype model is built to capture the crawler-formation interaction in MSC ADAMS based on the rigid body crawler kinematics. The virtual prototype simulator is supplied with mass properties of crawler shoe, mass, stiffness and damping characteristics of oil sand and external loads due to machine weight and contact forces to obtain the time variation of position, velocity and acceleration for the crawler–terrain engagement for given driving constraints. The results from the driving constraints yield a non-linear longitudinal motion of the crawler track assembly. The crawler track lateral and vertical displacements during translation-only motion fluctuates with maximum magnitudes of 0.7 and 3.6 cm. Similarly the fluctuating longitudinal, lateral and vertical velocities and accelerations have maximum magnitudes of 0.22, 0.046 and 0.56 m/s and 7.41, 1.73, and 34.9 m/s2, respectively. This research provides a strong foundation for further study on developing flexible crawler track model for predicting crawler shoes dynamic stress distributions, cracks development and propagation and fatigue analysis during shovel operations. [ABSTRACT FROM AUTHOR]

This paper describes the design and implementation of a system for rendering virtual shape through vision, haptic and sound. The system consists of a haptic strip that physically renders virtual curves. A flexible capacitive touch sensor (FCTS) is integrated with the haptic strip, and allows the system to track the position of the user's fingers on the strip. According to the position, the system renders curve properties such as curve shape, inflexion points and curvature through sound metaphors. The goal of this sonification approach is to strengthen the user's understanding of the shape of a virtual prototype, and to inform the user about geometrical attributes that could otherwise remain unseen. Such unseen attributes may either be a result of limitations in the visual and haptic display hardware or a result of limitations in human perception. [ABSTRACT FROM PUBLISHER]

A procedural modelling method based on model combination and spatial semantic constraint is proposed to realize the automatic modelling of high-speed railway scenes for management decisions and scientific experiments at different stages. The construction and description of basic-element models were first discussed in detail according to the fixed characteristics of the geometric appearances of and the spatial relationships between the components of high-speed railways. Then, spatial semantic constraint rules and scene mapping and instantiation methods were designed to accurately and rapidly integrate various basic-element models for automatically generating high-fidelity three-dimensional high-speed railway scenes. Finally, a prototype modelling system was developed to implement preliminary experiments. The experimental results show that the method proposed in this article is suitable for the automatic generation of virtual high-speed railway scenes by combining sophisticated basic-element models in a seamless manner. Modelling operations and professional knowledge are decoupled to reduce the complexity and difficulty of multidisciplinary collaborative modelling, which improves the modelling efficiency of virtual high-speed railway scenes. [ABSTRACT FROM AUTHOR]

A carer or teacher often plays the role of proxy or spokesperson for a person living with an intellectual disability or form of cognitive or sensory impairment. Our research undertook co-design with people living with cognitive and sensory impairments and their proxies in order to explore new ways of facilitating communication. We developed simple functioning interactive prototypes to support people with a diverse range of competencies to communicate and explore their use. Deployment of the prototypes enabled use, appropriation anddesign after designby our two participant groups; adults living with cognitive or sensory impairments and children identified with language delays and autism spectrum disorder. The prototypes supported concrete expression of likes, dislikes, capabilities, emotional wants and needs and forms of expression that hitherto had not been fostered, further informing design. Carers and designers were surprised at the ways in which the technology was used and how it fostered new forms of social interaction and expression. We elaborate on howdesign after designcan be an effective approach for engaging people living with intellectual disabilities, giving them greater capacity for expression and power in design and offering the potential to expand and deepen their social relationships. [ABSTRACT FROM AUTHOR]

The use of haptics in virtual reality and video games has received growing attention as a means of enhancing the sensation of immersion in these environments. The sensation of touching virtual objects not only augments the impression of reality but also can improve the performance. However, the design of haptic interactions is not an easy task, and it usually needs a great effort due to the absence of powerful prototyping toolkits. Thus, this article proposes a vibrotactile prototyping toolkit for Eccentric Rotating Mass actuators named VITAKI. The main objective of this platform is to facilitate the prototyping and testing procedures of new vibrotactile interaction techniques for Virtual Reality and video games. A detailed description of the design of the system is provided, presenting the hardware and software elements that make up the VITAKI toolkit. In addition, its application to two different examples to illustrate its use is provided. Finally, a preliminary evaluation of this toolkit is presented. This evaluation is divided into two main stages. On one hand, a study of Olsen’s criteria is performed to analyze its general capabilities. On the other hand, a comparison with previously presented proposals is included too. These two analyses, together with other experiments where the devices created with the toolkit were tested by end users, highlight its main features and its advantages over other proposals. [ABSTRACT FROM PUBLISHER]

This paper explores how consumers evaluate both virtual and physical prototypes of furniture products. In this study, the consumers are non-technical people without earlier experience on evaluating virtual prototypes. The evaluation task was not done in a laboratory but at a furniture fair with two stands. The physical prototypes were hand-made products presented in a typical fair stand, whereas the virtual ones were actual size, 3D visual images of the products. There were 28 fair visitors participating in the evaluation experiment. The result reveals that there were no differences between the descriptions of physical and virtual prototypes by consumers who evaluated Product Properties. In evaluating virtual prototypes, the consumers came up with more development ideas than when evaluating physical prototypes. Our study proposes that virtual prototypes are useful when consumers' participation in the development process is desirable. [ABSTRACT FROM AUTHOR]

Designing physical interfaces, like the doors of consumer products, able to elicit a positive experience when interacting with them, is now becoming a key priority for design teams. One of the main difficulties of this activity consists of translating all the qualitative perceptual feedback that can be captured from the customers into quantitative specifications. Performing this translation is not an easy task since there are still no effective tools, methodologies or approaches able to guide designers in accomplishing this goal. To overcome this lack a reverse engineering-based approach is proposed. This one guides designers towards the modelling, parameterisation and reproduction of the behaviour of the product interface to be redesigned, within a multisensory virtual environment. The intent is to let the user experience different behaviours in order to ask them to identify the desired one or to express preferences for updating it in real-time according to indications provided. At the same time a detailed physics model, built by the designer, is used to convert this desired behaviour, into detailed quantitative design specifications. The method is defined as a reverse engineering one for two main reasons: first the new interaction is derived on the basis of the behaviour of an existing interface, taken as reference, and second a reverse engineering of the user's perceptual preferences is applied to derive new specifications. A case study is discussed to demonstrate the method effectiveness and to highlight its limitations. [ABSTRACT FROM PUBLISHER]

In common industrial practice the definition of shapes of styling products is performed by product designers. They usually produce aesthetic shapes by handcrafting scale models made of malleable material like clay, and often expensive physical prototypes are also manufactured. The paper describes a Desktop Mechatronic System (DMS) that has been conceived to support designers in the creation, evaluation and modification of aesthetic virtual shapes. The objective in designing this system is to develop a system allowing a continuous and smooth free hand physical interaction with a virtual shape, which is rendered through a dynamic cross-sectional contour or curve in three-dimensional (3D) space. The DMS is a useful tool for designers, who are not certain about the quality of the shape of the product, and can use it for testing out ideas. The DMS consists of a servo-actuated developable metallic strip, which reproduces 3D cross-sectional contours, which has been devised and implemented by using the Minimal Energy Curve (MEC) spline approach in which the equidistant interpolation points scheme has been adopted to imitate the virtual object created via a Computer Aided Design (CAD) tool on a physical bendable strip-like surface. [ABSTRACT FROM AUTHOR]

The paper describes an application based on Virtual and Augmented Reality technologies specifically developed to support maintenance operations of industrial products. Two scenarios have been proposed. In the first an operator learns how to perform a maintenance operation in a multimodal Virtual Reality environment that mixes a traditional instruction manual with the simulation, based on visual and haptic technologies, of the maintenance training task. In the second scenario, a skilled user operating in a multimodal Virtual Reality environment can remotely train another operator who sees the instructions about how the operations should be correctly performed, which are superimposed onto the real product. The paper presents the development of the application as well as its testing with users. Furthermore limits and potentialities of the use of Virtual and Augmented Reality technologies for training operators for product maintenance are discussed. [ABSTRACT FROM AUTHOR]

In this paper, a framework utilising virtual and rapid prototyping to aid design of a shuttlecock skirt was proposed and implemented. A standard template for flow simulation on ANSYS® CFX was developed to predict the aerodynamic performance of the virtual prototypes, with focus on reduced simulation time and complexity. This forms the basis of the computer aided design model – computational fluid dynamics – performance evaluation loop in the proposed framework. Steady state flow simulation was conducted for three simple computer aided design models of shuttlecocks, with different gap dimensions on the skirt. Wind tunnel drag study of the models reproduced through rapid prototyping validated the simulation result. The proposed methodology can also be applied to the existing design process for integration of virtual and rapid prototyping to reduce the burden of design iteration. [ABSTRACT FROM AUTHOR]

The design of a new product requires a series of validations before its approval and manufacture. Virtual prototyping based on mixed reality technology seems a promising technique, especially when applied to the design review of products that are characterised by interaction with users. This paper presents a new methodology that allows the collaborative design review and modification of some components of automotive interiors. Professionals can work together through a mixed reality distributed design platform by interacting intuitively and naturally with the virtual prototype of the product. The methodology has been validated by means of tests with users, aiming at assessing the effectiveness of the approach, and at identifying potential usability issues. [ABSTRACT FROM AUTHOR]