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To ensure that the discrete element model of the coal wall accurately reflects the actual cutting process of coal and rock during virtual prototype simulation of mining equipment, this study aims to expedite the development of intelligent mining machinery. Using coal samples from the 4602 working face of Yangcun Coal Mine, operated by Yanzhou Coal Mining Group, we conducted coal rock packing experiments and uniaxial compression tests to obtain the packing angle and compressive strength of the coal samples. Based on the experimental results, we designed Plackett–Burman experiments (PB experiments), steepest ascent experiments, and Box-Behnken experiments to study the influence of particle contact mechanics parameters and bonding mechanics parameters on the packing angle and compressive strength, using the packing angle and compressive strength as response variables. Our objective is to minimize the relative error between the simulated packing angle and the measured packing angle. We solved and optimized the parameter calibration model and conducted simulation calibration experiments based on the optimization results. A comparative analysis with the actual test results revealed that the maximum relative errors between the simulated and measured values for the packing angle and compressive strength were only 2.9% and 5.0%, respectively. Additionally, a discrete element model of a typical working face coal wall was established based on the parameters obtained from this calibration method. A bidirectional coupling model of the cutting process between the coal and rock was created using EDEM-RecurDyn to simulate the rigid-flexible coupling of the coal cutter. An experimental coal wall model was constructed based on similarity theory, and both simulation and physical experiments were conducted. The evaluation metrics for comparison were the time-domain and frequency-domain characteristics of the drum's vibration signals. The maximum relative error for the time-domain signal characteristics between the two experimental setups was only 4.19%, while the maximum relative error for the frequency-domain signal characteristics was 3.75%. This validates the feasibility of the proposed calibration method for the discrete element coal wall model and the accuracy of the calibration results. Furthermore, it demonstrates that the constructed discrete element coal wall accurately represents the actual coal and rock properties. The virtual simulation based on this model effectively replicates the interaction process between mining machinery and coal, providing a safe, efficient, and low-cost technological approach for performance analysis of mining equipment and intelligent control of supporting devices. [ABSTRACT FROM AUTHOR]

System dynamics serves as a crucial foundation for evaluating the performance of mechanical auxiliary equipment. To enhance the stability and reliability of the badminton launch process, structural design and dynamic analysis were conducted on a mode-adjustable, precise control badminton serving mechanism. The combination of eccentric crank-slider mechanism, stretched springs, and electromagnets was used in mechanical structures, which could effectively effectively improve the smoothness of the badminton in the launching process. The virtual prototype of badminton serving machine was established and imported into ADAMS for dynamic simulation analysis, verifying the correctness of the serving and retrieving mechanisms. Using the aerodynamic equations, the trajectory of badminton movement under different working parameters was simulated and analyzed. The dynamic analysis results show that the design of the launching and catching mechanisms is scientific and effective. The launch angle and initial velocity are the key factors that determine the trajectory of the badminton. [ABSTRACT FROM AUTHOR]

This paper addresses and compares the modeling of typical EMI filters used in three-phase power equipment obtained through two different approaches, namely, physical and behavioral. Firstly, an innovative physical EMI filter modeling procedure is presented, which relies on an analytical formulation in terms of chain-parameters matrices and allows for an easy evaluation of its attenuation characteristics. The considered procedure builds an overall filter model by combining simple components models, requiring the determination of only a limited number of parasitic elements. Furthermore, the latter can be easily estimated without the need to build any prototype, avoiding the costly trial-and-error design procedures currently applied in the industrial context. Additionally, the considered physical model is tailored for high-power filters, built with thick wires, while most of the physical models available in the literature are aimed at small-sized filters built on printed circuit boards. The procedure is validated step by step, discussing the accuracy of each component model and its impact on overall accuracy compared to the actual measurements of the final assembled filter. Secondly, a behavioral modeling procedure is presented, which is based on external measurements performed on the filter prototype and provides an equivalent circuit model. Specifically, it extends to three-phase filters a circuit model previously developed for the single-phase case. Lastly, a critical comparison between the proposed physical and behavioral models is presented, highlighting the strengths and limitations of both and suggesting optimal uses for each. [ABSTRACT FROM AUTHOR]

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]

This paper is devoted to presenting the results of the computer-aided design, the multibody dynamic analysis, and the proportional-derivative control synthesis of an adaptive mechanism serving as a lifting table. More specifically, the first part of the manuscript deals with the methodological approach and the mathematical background employed in the entire research work, whereas the second part of the present paper is focused on the model development and the numerical experiments carried out in this investigation. The analytical derivations presented herein demonstrate that the desired adaptive behavior can be successfully obtained for the virtual prototype of the lift mechanism devised in this investigation. Furthermore, a detailed CAD model of the proposed design was constructed in this investigation using SOLIDWORKS. To this end, particular attention was paid to the actual assembly and disassembly of each mechanical component, in conjunction with the choice of the actuators and sensors that are necessary for the proper functioning of the lifting mechanism. Then, a three-dimensional multibody model was developed starting from the CAD model of the virtual prototype devised in this investigation. The resulting multibody model, following appropriate simplifications, was subsequently imported into the MATLAB virtual environment, thereby allowing for readily performing kinematic and dynamic simulations of the nonlinear behavior of the mechanical system under study by using the SIMSCAPE MULTIBODY computational software. By doing so, the development of an appropriate control strategy, as well as the analysis of its behavior under loading and unloading goods conditions, was carried out and tested in the case of four different scenarios considered as the case study. For this purpose, the applicative scenarios considered are: 1) an impulsive loading scenario; 2) a progressive loading scenario; 3) an impulsive unloading scenario; 4) and a progressive unloading scenario. The performance of the feedforward plus feedback control strategy devised in this study was discussed based on several computer simulations. Numerical simulations demonstrate that the desired adaptive behavior is successfully obtained for the virtual prototype of the lift table designed in this study. [ABSTRACT FROM AUTHOR]

Cyberattacks aim to access confidential information or disrupt system functionality. These days, they can take the form of attacks that give the attacker complete control over the victim's computer. Remote Access Trojans (RAT) are malware designed for these purposes. RAT gives an attacker direct access to a victim's computer and allows him to interact with the victim to steal confidential information, spy on him in real time, or interact directly with him through a dialogue box. RATs are used for information theft, surveillance, and extortion of victims. This study installed multiple virtual machines as a prototype for both the attacker and the victim, interconnected on a Local Area Network (LAN). RAT installations were explored using Mega RAT version 1.5 Beta. Ultimately, various RAT attacks were executed on target machines, and a range of static and dynamic analysis tools were employed to identify RAT. The scenarios implemented on the LAN demonstrated that RATs can be built and used with ease. Furthermore, their attacks can be identified through static or dynamic analysis using various freely available tools. The findings show that the static detection approach to identify RAT malware is more user-friendly compared to dynamic methods. However, dynamic detection can be easily performed using cost-free software. [ABSTRACT FROM AUTHOR]

The purpose of the PRODEC scenario‐based design method is the incremental cross‐fertilization and refinement of procedural scenarios and declarative configurations. It uses virtual prototypes of the developed systems (mainly life‐critical systems) to conduct human‐in‐the‐loop simulations (HITLSs). Based on human systems integration (HSI) principles and criteria, as well as expertise and experience in the domain at stake, this HSI approach grounded in virtual environments requires a clear definition of physical and cognitive tangibility metrics to assess the distance between virtual and tangible (grasp) dimensions of the system being developed when it is put to work. PRODEC considers human and machine systems described in terms of structures and functions incrementally designed using procedural scenarios (i.e., stories) in task and activity networks, which provide life to declarative configurations (i.e., system's functions and structures). This active modeling and simulation process enables the discovery of emergent structures and functions of the system being developed when it is virtually operated. PRODEC's use is illustrated in an example. We discuss the use of PRODEC and its results as to how they can be used with digital twins. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Ordnance Equipment Engineering is the property of Chongqing University of Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Ordnance Equipment Engineering is the property of Chongqing University of Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Industry 4.0 conceptualizes the automation of processes through the introduction of technologies such as artificial intelligence and advanced robotics, resulting in a significant production improvement. Detecting defects in the production process, predicting mechanical malfunctions in the assembly line, and identifying defects of the final product are just a few examples of applications of these technologies. In this context, this work focuses on the detection of ultrasound probes' surface defects, with a focus on Esaote S.p.A.'s production line probes. To date, this control is performed manually and therefore biased by many factors such as surface morphology, color, size of the defect, and by lighting conditions (which can cause reflections preventing detection). To overcome these shortfalls, this work proposes a fully automatic machine vision system for surface acquisition of ultrasound probes coupled with an automated defect detection system that leverage artificial intelligence. The paper addresses two crucial steps: (i) the development of the acquisition system (i.e., selection of the acquisition device, analysis of the illumination system, and design of the camera handling system); (ii) the analysis of neural network models for defect detection and classification by comparing three possible solutions (i.e., MMSD-Net, ResNet, EfficientNet). The results suggest that the developed system has the potential to be used as a defect detection tool in the production line (full image acquisition cycle takes ~ 200 s), with the best detection accuracy obtained with the EfficientNet model being 98.63% and a classification accuracy of 81.90%. [ABSTRACT FROM AUTHOR]

Real-time hybrid simulation has gained popularity over the last 20 years as a viable and cost-effective method of testing dynamic systems that cannot be tested using traditional methods. The emergence of multi-axial Real-time Hybrid Simulation (maRTHS) has led to an increase in the allowable fidelity of the numerical and experimental substructures. The testing community can now replicate multiple-degree-of-freedom (MDOF) responses of both substructures and thus can perform more representative tests. However, with this increased fidelity of the substructures comes an increased complexity of controlling these components. Specifically, multi-axial hydraulic actuator assemblages require nonlinear coordinate transformations to derive plant displacements as the force transducers on the actuators are not capable of performing this task directly. Recently, benchmark problems have been provided to the RTHS community in the form of virtual simulations. Virtual simulation refers to a fully virtual testing methodology where numerical and physical components are represented virtually. This approach enables the RTHS community to evaluate various control algorithms without the need to recreate physical components. This project aims to demonstrate the capability of computer vision-based displacement tracking in a realistic virtual simulation of the experimental substructure in avoiding excess nonlinear coordinate transforms. The tracking algorithm utilizing the Lucas-Kanade optical flow method is tested in the virtual simulation environment which is set up using real-time 3D creation engine, Unreal Engine 4 (UE4), and computer graphics software, Blender. This environment interfaces with MATLAB/Simulink, more specifically "Simulation Tool for v-maRTHS benchmark" developed for multi-axial tests. The result of this study establishes a novel framework for applying computer vision-based tracking algorithms and sensing in v-maRTHS simulations using simulated cameras within virtual simulation environments. A computer vision displacement tracking algorithm is developed and optimized to work in tandem with a MIMO PI controller to reduce tracking time delays within 31.25 milliseconds while tracking the nodal displacement and rotation of the frame within a normalized RMSE of 1.24 and 1.10 respectively. [ABSTRACT FROM AUTHOR]

The Rockaways Peninsula faces issues related to congestion and power outages during times of peak usage. Additionally, it is susceptible to disruptions caused by disasters such as hurricanes and storms. In this paper, we propose a new methodology that employs multi-paradigm modelling and control for the design and implementation of interconnected microgrid systems in the Rockaways. Microgrids are small-scale power networks that incorporate renewable energy technologies for power generation and distribution to enhance the control of energy supply and demand. Multi-paradigm modelling is employed to describe microgrids' dynamic behavior more accurately by integrating system dynamics, agent-based modelling, as well as discrete event and continuous time simulation. We use agent-based models to describe the behavior of separate microgrid elements and the microgrid as a whole. Discrete event/continuous time simulation is used to analyze real-time operation of electrical parameters, such as voltage, current and frequency. Thus, the design, analysis and performance of microgrids are improved. Also, control strategies are used for the purpose of enabling the microgrids to operate effectively by responding to changes in power supply and demand and minimizing the effects of disturbances. The findings of this study demonstrate the feasibility and resilience benefits of incorporating multi-paradigm modelling and control in the design and management of microgrid systems in the Rockaways, which can result in the development of more durable, efficient, and sustainable energy systems in the region. [ABSTRACT FROM AUTHOR]

Trajectory-following control is the basis for the practical application of an articulated virtual rail train transportation system. In this paper, a planar nonlinear dynamics model of an articulated vehicle is derived using the Euler–Lagrange method. A trajectory-following control strategy based on the first following point is proposed, and a feedback linearization control algorithm is designed based on the vehicle dynamics model to achieve the trajectory following of the rear vehicle. Based on the target trajectory formed by the first following point and measured by virtual sensors, a vector analysis method grounded in geometric relationships is proposed to solve in real time for the desired position, velocity, and acceleration of the vehicle. Finally, a MATLAB/SIMPACK dynamics virtual prototype is established to test the vehicle's trajectory-following effectiveness and dynamics performance under lane change and circular curve routes. The results indicate that the control algorithm can achieve trajectory following while maintaining good vehicle dynamics performance. It is robust to variations in vehicle mass, vehicle speed, tire cornering stiffness, and road friction coefficient. [ABSTRACT FROM AUTHOR]

Featured Application: Prediction and selection of the clamping conditions of large-size workpieces for the purpose of milling, based on modal tests and milling simulations. Vibrations occurring during milling operations are one of the main issues disturbing the pursuit of better efficiency of milling operations and product quality. Even in the case of a stable cutting process, vibration reduction is still an important goal. One of the possible solutions to obtain it is selection of the favorable conditions for clamping the workpiece to the machine table. In this paper, a method for predicting and selecting the clamping condition of a large-size workpiece for the reduction in vibrations during milling is presented. A modal test of the workpiece is performed first for a selected set of tightening screw settings. Next, one milling pass is performed to obtain reference data which are then used to tune the hybrid computational model. In the subsequent step, milling simulations are performed for a set of tightening variants, and the best one is selected, providing the lowest vibrations, assessed as the root mean square (RMS) of vibration displacements. In this paper, the description of the clamping selection procedure, key elements of the simulation model, and simulation and experimental results obtained for the milling of the test workpiece performed for a set of different clamping conditions are provided. The proposed method accurately predicts not only the best but also the worst clamping conditions. [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]

A knotter is a core component for the automatic bundling of agricultural materials, and a knotter with double-fluted discs is one type. Currently, the research on knotters with double-fluted discs has gradually transitioned from structural design to reliability optimization. To address rope-clamping failures in the rope-clamping drive mechanisms in knotters, the specific failure position of the rope-clamping mechanism and the failure causes were analyzed first. The redesign of the rope-clamping drive mechanism in knotters with double synclastic fluted discs was proposed, including structure optimization and 3D modeling using the GearTrax/KISSsoft and SolidWorks software. A virtual prototype model of a knotter with a flexible rope was established by combining ANSYS with the ADAMS software. A rigid–flexible coupling dynamic simulation of the knotter was carried out using ADAMS, and the simulation results were used as the data input for the ANSYS nCode DesignLife module for the fatigue life simulation of the weak parts (the worm shaft) of the knotter. The operation test results for the rope-clamping drive mechanism indicate that the redesigned rope-clamping drive mechanism is reliable in transmission, with a rope-clamping success rate of 100%. The actual operation times for the worm shaft exceed the minimum fatigue life obtained through joint simulation. The applied joint simulation method has high simulation accuracy. [ABSTRACT FROM AUTHOR]

The growing market for lightweight robots inspires new use-cases, such as collaborative manipulators for human-centered automation. However, widespread adoption faces obstacles due to high R&D costs and longer design cycles, although rapid advances in mechatronic engineering have effectively narrowed the design space to affordable robot components, turning the development of lightweight robots into a component selection and integration challenge. Recognizing this transformation, we demonstrate a practical framework for designing lightweight industrial manipulators using a case-study of indigenously developed 5 Degrees-of-Freedom (DOF) cobot prototype. Our framework incorporates off-the-shelf sensors, actuators, gears, and links for Design for Manufacturing and Assembly (DFMA), along with complete virtual prototyping. The design cycle time is reduced by approximately 40% at the cost of cobot real-time performance deviating within 2.5% of the target metric. Our physical prototype, having repeatability of 0.05mm calculated as per the procedure defined in ISO 9283:1998, validates the cost-effective nature of the framework for creating lightweight manipulators, benefiting robotic startups, R&D organizations, and educational institutes without access to expensive in-house fabrication setups. [ABSTRACT FROM AUTHOR]

To amplify the displacement of the radiation shell, a double-shell type-IV curved hydroacoustic transducer was proposed. Through Ansys finite element simulation, the vibration modes of the transducer in different stages and the harmonic response characteristics in air and water were studied, and the bandwidth emission of the hydroacoustic transducer was achieved. By optimizing the size of each component, the resonant frequency of the transducer is 740 Hz, the maximum conductivity was 0.66 mS, and the maximum transmitting voltage response was 130 dB. According to the optimized parameters, a longitudinal acoustic transducer prototype was manufactured, and a physical test was conducted in an anechoic pool. The obtained resonant frequency was 750 Hz, the maximum conductivity was 0.44 mS, the maximum transmitting voltage response was 129.25 dB, and the maximum linear dimension was 250 mm, which match the simulated value of the virtual prototype and meet the expected requirements. [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]

Large displacement axial piston pumps (>500 mL/r) are the core power components of large construction machineries' hydraulic system. The demand for higher power in large construction machinery is increasing. High pressure and large displacement are the primary areas of focus for enhancing the power of piston pumps. However, this may exacerbate issues with the pumps' output characteristics, such as flow or pressure pulsation and leakage. This paper uses a cross angle of the swash plate to optimize the pulsation and leakage for the 750 mL/r axial piston pumps. Piston and cylinder dynamics affect flow and pressure pulsations, and leakage is related to cylinder tilting behaviour. The pumps' flow distribution, kinematics and dynamics of the piston and cylinder, output flow and pressure are analysed. A virtual prototype is built based on the rigid-flexible-hydraulic coupling model. The oil film flexible body of the valve plate pair is added. The maximum principal stress and strain of the oil film flexible body are used as indicators of tilting behaviour. Effects of the cross angle on output characteristics and tilting behaviour are investigated through the numerical solution. Results show that the cross angle of −0.5° can effectively reduce the pressure pulsation rate by 0.89% and the flow pulsation rate by 3.77% while optimizing the tilting behaviour of the cylinder. In addition, the cylinder's tilting behaviour is verified by the wear detection on the valve plate surface. • Use cross angle to optimize pulsation and leakage of 750 mL/r piston pumps. • Construct a model of rigid-flexible-hydraulic coupling for 750 mL/r piston pumps. • Add an oil film flexible body to express the cylinder tilting behaviour. • Analyze the pump pulsation and cylinder tilting motion with various cross angles. • A cross angle of −0.5° has the best effect on pump pulsation and cylinder tilting. [ABSTRACT FROM AUTHOR]

Due to the EV (Electric Vehicles) charging stations are characterized by weak damping and low inertia, the EV with a high degree of uncertainty can easily have an impact on the stability of the charging station system. Therefore, this paper proposes an optimization control method to improve the system inertia effect based on the fractional order impedance model of the charging station. This paper presents a study on establishing a fractional impedance model for charging stations, using the deviation between theoretical impedance spectra and actual measurements as a criterion. The goal is to enhance system inertia and optimize the parameters of the fractional-order controller to improve the supporting capacity of the charging station system and enhance its dynamic response. Initially, considering the fractional characteristics of the EV load, a fractional impedance model of the charging station is established. The analysis demonstrates that the fractional-order capacitor provides inertia to the system, enhancing its inertia support capability. In addition, a virtual inertia control strategy based on fractional-order PID (FOPID) is designed. Finally, an improved particle swarm optimization algorithm is utilized to optimize the control parameters. Through experimental verification under different operating conditions, it has been demonstrated that the fractional-order control strategy can achieve a dynamic response time of approximately 0.025s and limit the voltage deviation within 5%. Furthermore, the rotational inertia can rapidly increase to the maximum value satisfying the objective function within 0.05s. The results indicate that this control method effectively suppresses the DC voltage and power oscillations in the distribution grid. [ABSTRACT FROM AUTHOR]

Copyright of Machine Tool & Hydraulics is the property of Guangzhou Mechanical Engineering Research Institute (GMERI) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The object of this study is the process of determining the optimal method for prototyping interactive virtual systems using the principle of multi-criteria optimization. The paper addresses the task to design tools for evaluating prototyping methods and introduces software developed to identify the best option according to priority criteria. The optimal prototyping method was chosen based on the maximum value of the membership function with indicators of 0.3, 0.7, and 1. Thus, the best method for the given task is rapid prototyping, with a membership function value equal to 1. These results have made it possible to solve the problem by evaluating fuzzy preference relations on a set of alternatives. Additionally, a relation convolution was constructed, from which a subset of non-dominated alternatives was identified. The key features of the proposed approach are obtaining clear quantitative evaluation parameters by processing descriptive, non-unified, and non-formalized input data. The fuzzy preference relations for the set of alternatives are explained by the analysis of the most common methods for prototyping interactive systems. The developed information system could be used for managerial decision-making regarding the selection of optimal prototyping option from several possibilities, by comparing methods based on predefined criteria with arbitrary weighting coefficients. The result of the research is a universal system adaptable to specific user tasks. The resulting data will contribute to improving the efficiency of prototyping and, consequently, reducing costs [ABSTRACT FROM AUTHOR]

Wearable robots are emerging as a viable and effective solution for assisting and enabling people who suffer from balance and mobility disorders. Virtual prototyping is a powerful tool to design robots, preventing the costly iterative physical prototyping and testing. Design of wearable robots through modelling, however, often involves computationally expensive and error-prone multi-body simulations wrapped in an optimization framework to simulate human–robot–environment interactions. This paper proposes a framework to make the human–robot link segment system statically determinate, allowing for the closed-form inverse dynamics formulation of the link–segment model to be solved directly in order to simulate human–robot dynamic interactions. The paper also uses a technique developed by the authors to estimate the walking ground reactions from reference kinematic data, avoiding the need to measure them. The proposed framework is (a) computationally efficient and (b) transparent and easy to interpret, and (c) eliminates the need for optimization, detailed musculoskeletal modelling and measuring ground reaction forces for normal walking simulations. It is used to optimise the position of hip and ankle joints and the actuator torque–velocity requirements for a seven segments of a lower-limb wearable robot that is attached to the user at the shoes and pelvis. Gait measurements were carried out on six healthy subjects, and the data were used for design optimization and validation. The new technique promises to offer a significant advance in the way in which wearable robots can be designed. [ABSTRACT FROM AUTHOR]

Human–robot collaboration (HRC) has emerged as a promising frontier within the construction industry, offering the potential to enhance productivity, safety, and efficiency. The effectiveness of HRC critically depends on the degree of trust that workers place in their robots, and establishing a seamless level of trust in robots is essential to realize the full benefits of HRC. Despite the extensive exploration of trust dynamics in various industries, there is a notable research gap with regard to trust in construction robots, which possess distinctive characteristics in terms of appearance, capabilities, and interaction compared to robots in other sectors. Therefore, in this study, we analyzed trust dynamics within the context of HRC during construction tasks. Both subjective survey data and objective psychophysiological data—including heart rate variability (HRV), electrodermal activity (EDA), and electroencephalogram (EEG)-based emotional valence and arousal—were employed as human trust measures. We conducted experiments for bricklaying tasks in an immersive virtual construction environment and analyzed multifaceted robot factors—including workspace environment, level of interaction, and robot speed, proximity, and angle of approach—and their relationships with human trust measures using statistical analysis, such as t -test, two-way ANOVA, Spearman's rank correlation, and moderation analysis. The results indicated that workspace environment and level of interaction were the most significant robot factors affecting human trust. EDA exhibited the most sensitivity to variations in robot factors. It was also observed that the effect of speed, proximity, and angle of approach were also dependent on level of interaction and type of workspace environment. There was a significant positive correlation between proximity and perceived trust. The findings of this study contribute to the optimization of robot design and interaction protocols for construction tasks, fostering greater worker trust, and enhancing project productivity and efficiency. [ABSTRACT FROM AUTHOR]

This paper proposes an approach for training visuo-haptic object recognition models for robots using synthetic datasets generated by 3D virtual simulations. In robotics, where visual object recognition has witnessed considerable progress due to an abundance of image datasets, the scarcity of diverse haptic samples has resulted in a noticeable gap in research on machine learning incorporating the haptic sense. Our proposed methodology addresses this challenge by utilizing 3D virtual simulations to create realistic synthetic datasets, offering a scalable and cost-effective solution to integrate haptic and visual cues for object recognition seamlessly. Acknowledging the importance of multimodal perception, particularly in robotic applications, our research not only closes the existing gap but envisions a future where intelligent agents possess a holistic understanding of their environment derived from both visual and haptic senses. Our experiments show that synthetic datasets can be used for training object recognition in haptic and visual modes by incorporating noise, performing some preprocessing, data augmentation, or domain adaptation. This work contributes to the advancement of multimodal machine learning toward a more nuanced and comprehensive robotic perception. [ABSTRACT FROM AUTHOR]

In this work, the Quality Function Deployment (QFD) and Failure Mode and Effects Analysis (FMEA) methodology based on the "Design for X" concept is studied to define the design criteria of the mechanical characteristics of an EOD robot and validated with a virtual prototype of an Explosive Ordnance Disposal (EOD) robot. The objective is the application of this methodology to obtain a product that meets the quality and reliability specifications, considering the user’s needs as input data. To validate this methodology, the technicians of the UDEX (Explosive Ordnance Disposal Unit), the mechanical characteristics of the previous version JVC 0.2 developed by the research team of the National University of San Agustin (UNSA), the minimum specifications of the robots participating in the League of Rescue Robots and the application to work in real environments were taken as a case study. The results indicate that the application of the proposed methodology has significantly improved the quality and reliability of the design. To validate the effectiveness of this methodology, a virtual prototype, called JVC 0.3, was created using SolidWorks modelling software, a significant weight reduction of 27.13 % was achieved and the operating speed was increased to 1 km/h under optimal conditions. Technical analysis of the JVC 0.3 showed significant improvements in several key areas, such as increased modularity for easier assembly and maintenance, decreased overall weight, increased torque and speed, and increased stability during operation. These factors are essential for the practical application of EOD robots in real field operations carried out by specialized units such as UDEX. [ABSTRACT FROM AUTHOR]

(1) Background: Quality inspection robots are widely used in automated production lines. However, the design cycle is long, iteration costs are high, and algorithm development is challenging. It is difficult to perform effective validation during the design phase. Applying virtual reality technology to simulate quality inspection robot workstations offers a new approach to addressing the issues. (2) Methods: The research creates a simulation platform for quality inspection robot workstations based on a virtual reality architecture. The platform creates an immersive quality inspection robot workstation operation interface and conducts testing of the inspection process, thereby validating the rationality of the quality inspection robot workstation design. Building upon this foundation, we conducted experimental comparisons of various defect detection algorithms. (3) Results: Compared to the traditional YOLOv7 algorithm, the improved YOLOv7 algorithm achieved an 18.1% increase in recognition precision. Experimental results demonstrate that the quality inspection robot workstation simulation platform can be applied to validating workstation design proposals. (4) Conclusions: It has a positive impact on reducing the research and development costs of quality inspection robot workstations and shortening the defect recognition algorithm development cycle. [ABSTRACT FROM AUTHOR]

In this paper, the kinematic synthesis of a parallel Gough-Stewart platform mechanism is addressed in order to achieve the motion of the working part of the mechanism along a prescribed trajectory. A virtual prototype of this platform was created in the environment of the dynamics of systems bodies program ADAMS. In the process of cosimulation of MATLAB, MATLAB/Simulink and ADAMS, the input trajectories of actuator velocities necessary to achieve the desired motion of the effector point were identified. The trajectory was defined by parametric equations for the epitrochoid, hypocycloid, epicycloid and Archimedes spiral. The velocities of the actuators were derived by deriving the position vector of the distances between the base and platform points. The solution logic using the given software is presented by a block diagram. [ABSTRACT FROM AUTHOR]

Copyright of Machine Tool & Hydraulics is the property of Guangzhou Mechanical Engineering Research Institute (GMERI) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This paper presents the design of an intra-row obstacle avoidance shovel-type weeding machine. Theoretical analysis of intra-row weeding components guided the determination of the structures and parameters for key parts, including the signal acquisition mechanism, automatic obstacle avoidance mechanism, and weeding shovel. Furthermore, a hydraulic system was designed to support these functions. The design aims to optimize intra-row weeding operations, reduce labor costs, enhance weed control effectiveness, and prevent collisions between weeding equipment and grapevines. Through the construction of a mathematical model, the analysis determined the necessary minimum return speed of the hydraulic cylinder for the intra-row weeding shovel to avoid grapevines. We also established a reasonable range for the extension speed of the hydraulic cylinder to minimize areas missed during weeding. Further analysis showed that using the minimum return speed of the hydraulic cylinder effectively reduced missed weeding areas. A virtual prototype model of the weeding machine was created in ADAMS. Using the coverage rate of weeding operation as the evaluation index, single-factor simulation tests determined that the extension speed of the piston rod in the obstacle avoidance hydraulic cylinder and the forward speed of the weeding machine are the main influencing factors. The preset threshold of the control system, which triggered the automatic obstacle avoidance mechanism when the obstacle avoidance rod reached a specific angle (the "Angle Threshold"), was identified as a secondary influencing factor. Other factors were considered irrelevant. Hydraulic cylinder extension speed, weeding machine forward speed, and angle threshold were chosen as the influencing factors. Following the principles of a Box–Behnken experimental design, a quadratic regression combination experiment was designed using a three-factor, three-level response surface analysis method. The evaluation criterion focused on the coverage rate of weeding operation. A regression model was developed to determine the coverage rate of the weeding operation, identifying the optimal parameters as follows: obstacle avoidance hydraulic cylinder extension speed of 120 mm/s, forward speed of the weeding machine at 0.6 m/s, and an angle threshold of 18°. The optimized coverage rate of the weeding operation achieved 86.1%. This study serves as a reference for further optimization of intra-row weeding machines in vineyards and for other crops. [ABSTRACT FROM AUTHOR]

Copyright of Revista Educación en Ingeniería is the property of Asociacion Colombiana de Facultades de Ingenieria and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

With the development of game engines and graphics technology, open-world games have gained popularity all over the world recently. One of the key features of this genre is a realistic open world space for the players to explore, to the extent that some even deemed it as the prototype of virtual world and the Metaverse. However, in comparison with the growing world size, the player's spatial experience is a downward spiral. Interaction in an ever-increasing game space suffered from a repetitive design pattern which rendered the world grandeur on the surface but hollow deep down. How to find meaning in this seemingly hollow world and what game designers can learn from it? From a phenomenological perspective, this paper distinguishes "place" from "space," and, according to this, proposes a three-dimensional meaning structure of place, that is "orientation-identification-time," as a design approach to reconstruct a meaningful spatial experience in the game world. [ABSTRACT FROM AUTHOR]

A prosthetic knee is designed to replace the functionality of an anatomical knee in transfemoral amputees. The purpose of a prosthetic knee is to restore mobility and compensate amputees for their impairment. In the present research numerical modelling and simulation of a carbon fabric reinforced polymer made polycentric prosthetic knee with four‐bar mechanism was performed. Virtual prototyping with computer‐aided design and computer‐aided engineering software ensured geometric and structural stability of the knee design. The linkage mechanism, instantaneous centre's location and trajectory were investigated using multibody dynamics and analytical formulations. Computational simulations with a non‐linear finite element model were employed with joints, contact formulations and an orthotropic material model to predict the displacement, stress formulated and life of the knee prosthesis under static and cyclic loading conditions. Finite element analysis assessed the strength and durability of knee in accordance to standards. Maximum Principal stress of 155 MPa and life expectancy of 3.1 × 106 cycles were determined for the composite knee through numerical simulations ensuring a safe design. Experimental testing was also conducted as per standards and the percentage error was estimated to be 2.52%, thereby establishing the validity of the finite element model deployed. This type of simulation‐based approach can be implemented to efficiently and affordably design and prototype a prosthetic knee with desired functioning criteria. [ABSTRACT FROM AUTHOR]

This study presents the design, simulation, and prototype creation of a quadruped robot inspired by the Acinonyx jubatus (cheetah), specifically designed to replicate its distinctive walking, trotting, and galloping locomotion patterns. Following a detailed examination of the cheetah's skeletal muscle anatomy and biomechanics, a simplified model of the robot with 12 degrees of freedom was conducted. The mathematical transformation hierarchy model was established, and direct kinematics were simulated. A bio-inspired control approach was introduced, employing a Central Pattern Generator model based on Wilson–Cowan neural oscillators for each limb, interconnected by synaptic weights. This approach assisted in the simulation of oscillatory signals for relative phases corresponding to four distinct gaits in a system-level simulation platform. The design phase was conducted using CAD software (SolidWorks 2018), resulting in a 1:3-scale robot mirroring the cheetah's actual proportions. Movement simulations were performed in a virtual mechanics software environment, leading to the construction of a prototype measuring 35.5 cm in length, 21 cm in width, 27 cm in height (when standing), and weighing approximately 2.1 kg. The experimental validation of the prototype's limb angular positions and trajectories was achieved through the image processing of video-recorded movements, demonstrating a high correlation (0.9025 to 0.9560) in joint angular positions, except for the knee joint, where a correlation of 0.7071 was noted. This comprehensive approach from theoretical analysis to practical implementation showcases the potential of bio-inspired robotics in emulating complex biological locomotion. [ABSTRACT FROM AUTHOR]

Aiming at the lack of suitable machines for sweet potato seedling transplanting in China, and according to the agronomic requirements for the horizontal insertion method of sweet potato seedling, a new sweet potato seedling transplanting mechanism of planetary gear train was proposed based on the non-uniform transmission of deformed elliptical gear. The working principle of the transplanting mechanism was analyzed, and the kinematics modeling and analysis of the mechanism were carried out. The study established the numerical objectives of the transplanting mechanism and applied the theory of membership function to establish a mathematical model for the parameter-guided optimization design of the transplanting mechanism. The parameter-guided optimization design software was developed to obtain a set of optimal mechanism parameters that satisfied the motion trajectory of sweet potato transplanting and the posture of the transplanting arm. Based on the optimized parameters, the structure of the transplanting mechanism was designed, and a virtual prototype of the mechanism was created, whereby a virtual motion simulation of the transplanting mechanism was conducted to verify the correctness of the kinematics model and design of the mechanism. The high-speed photographic kinematics test of the mechanism prototype and sweet potato seedling transplanting tests were conducted to test the mechanism's kinematic characteristics and transplanting performance. The test results show that the test trajectory of the mechanism and test posture of the transplanting arm are almost consistent with the theoretical and simulation trajectory, meeting the agronomic requirements of the horizontal insertion method of sweet potato seedling; And when the rotary speed of the mechanism are 20 r/min and 30 r/min, the average success ratios of sweet potato seedlings transplanting are 90% and 82%, respectively, which prove the application feasibility of the mechanism in the practical machines. [ABSTRACT FROM AUTHOR]

This research and development study aimed to develop the prototype of virtual learning implemented in flipped classrooms and evaluate its effectiveness as a tool for developing Thai undergraduates' English receptive skills. To assess if the designed prototype is effective, a quasi-experimental method was employed. The experimental sample group consisted of 40 undergraduates studying English as a required general education subject at a university in Thailand. They were purposively selected as their English proficiency level did not meet the university requirement of not lower than 600 of the TOEIC scores for graduation. The actual TOEIC tests as a pre- and post-tests, have been employed to examine if the prototype was effective. The collected data from pre-and post-tests were then analyzed through the t-Test and ANOVA. The results showed that the designed prototype applied in teaching and learning through the three online virtual platforms, namely Second Life, VRChat, and the ClassStart in the flipped classrooms was effective for developing students' English receptive skills, as the overall development of students' English receptive skills, both listening and reading, as shown from their post-test English TOEIC scores had significant development, showing that the post-test scores were higher than those of their pre-test's. Therefore, applying this prototype to language teaching and learning as a pedagogy is highly advised. [ABSTRACT FROM AUTHOR]

The apparel industry has recently tried to lower its global pollution by switching to more sustainable production methods. One of these methods is virtual apparel sampling. It provides less waste, is cost-effective, faster, and more sustainable. Browzwear is one of the leading software companies that brands are using to produce virtual prototypes. Digitized fabric is a significant component in creating a proper virtual garment. To test how reliable digital fabrics are, specifically in Browzwear, researchers selected five fabrics with different weaves and knits. They then performed standard lab testing and compared the results with the properties provided by Browzwear testing. The fabrics were manipulated using different sewing techniques and were compared to their virtual renderings. These comparisons were put into a survey that was deployed to university students and faculty members with different experience levels to understand how similarities and differences were perceived. The study showed that it could not be determined whether Browzwear uses conventional testing methods to gather fabric data for their digital fabrics. Additionally, the visual survey indicated that participants preferred physical fabrics over digital ones, suggesting that digital fabrics do not create a perfect digital double at this time. [ABSTRACT FROM AUTHOR]

In collaboration with end-users and other key stakeholders, this paper describes an innovation process of designing and manufacturing customized assistive technologies for regional and remote communities. The project collaboratively identified the real-world problems of people living with spinal cord injuries, created design solutions to overcome these challenges, and worked with manufacturers to turn these solutions into actual products. The project embodied a co-design method to bring people living with spinal cord injuries, occupational therapists, researchers, designers, and manufacturers together to co-create new solutions to overcome common challenges. Data was collected through the following methods: a desktop study of the literature and the market; an innovation process via 4 x co-design workshops (Ideation, Design and Develop, Pitch and Feedback, Demonstration) from June 2021 to June 2022; a Research through Design methodology to design 3D-printed assistive technologies. Through iterative virtual and physical prototyping, and user testing, the most effective prototypes were refined into the optimal solution. The Project established an innovation process, including online consultation and workshops with end-users, that prioritize 3D printing of assistive technology prototypes; created a demonstrator for allied health engagement and testing; and completed end-user pilot group testing, such as materials, durability, grasping, biomechanical advantage, adaptability, etc. This innovation process produced a minimum viable product (MVP) that has enough features to attract early adopters and provide design validation early in the product development cycle. [ABSTRACT FROM AUTHOR]

Mobile robots with the ability to climb provide significant advantages in equipment contact operation and maintenance. In this work, an arc‐surface‐adsorption hexapod (ASAH) robot is designed for a class of internal cavity‐cylindrical‐type electrical equipment (ICCEE). The target of robot reliable movement on the ICCEE surface obtains its priority to be solved. Therefore, a matched‐specific motion control scheme is proposed. First, the mechanisms, adaptability, and motility of the ASAH robot are analyzed from a kinematic point of view. Subsequently, to solve the arc surface movement problem, this study proposes a novel six‐three‐legged composite gait and a "trapezoidal" foot tip trajectory algorithm, which improve safety in robot support phase movements and adsorption accuracy in the swing phase, respectively. In addition, based on the motion gait and trajectory, an active adsorption scheme is added to compensate for the position error. Finally, both virtual and physical prototype are constructed for performance verification. The simulation results verify the effectiveness of the proposed scheme in facilitating accurate motion on internal and external arc surfaces with different diameters, with an error lower than 5.3 mm/rad and 4.08× 10−6 $4.08\times \unicode{x0200A}1{0}^{-6}$ rad/mm for movements in the circumferential and axial directions, respectively. Experimental results and application performance in a nuclear power plant further verify the effectiveness of the gait and trajectory algorithm; an overall success rate of 85% in circumferential movement was achieved with a maximum load weight of 2.63 kg, representing 76% of the robot body weight. [ABSTRACT FROM AUTHOR]

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