Mechanical Design Research Articles

Thermal optimization of a high heat load liquid-metal-bath cooled mirror at the Hefei Advanced Light Facility.

Within the beamlines of diffraction-limited storage rings, the liquid-metal-bath cooling scheme is a prevalent choice for the cooling of high-heat load mirrors. This study employs the finite element analysis method to evaluate the thermal deformations of liquid-metal-bath horizontally deflecting mirrors in the Hefei Advanced Light Facility. In particular, we introduce a novel optimization strategy to obtain the optimal thermal deformation scenario, which also satisfies mechanical design requirements. Moreover, a concurrent optimization approach across multiple structural parameters of mirrors is adopted to attain globally optimal thermal deformation. Following the optimization of the mirror's structural parameters, the curvature radius increases to 227 km, while the residual slope error decreases to 36.3 nrad at 6eV in the meridian direction. The ray tracing analysis of the beam demonstrates a considerable reduction in the influence of thermal deformation on the beam's focal point. This work proposes an optimization method for designing cooling schemes under mechanical constraints.

A Tractable Truthful Profit Maximization Mechanism Design With Autonomous Agents

A Tractable Truthful Profit Maximization Mechanism Design With Autonomous Agents

Mechanical Design of the Superconducting Magnet for the 28 GHz ECR Ion Source ASTERICS

Mechanical Design of the Superconducting Magnet for the 28 GHz ECR Ion Source ASTERICS

Mechanical Structure Design of Pressure Sensors with Temperature Self-compensation for Invasive Blood Pressure Monitoring

Abstract Invasive blood pressure (IBP) is a fundamental part of basic cardiovascular monitoring. Conventional piezoresistive pressure sensors are limited in usage due to the high cost associated with equipment and intricate fabrication processes. Meanwhile, low-cost strain gauge pressure sensors have poor performance in the gauge factor (GF) and temperature insensitivity. Here, we report a mechanical structure design for diaphragm pressure sensors (DPSs) by introducing a compensation grid to overcome the aforementioned challenges. A simplified model is established to analyze the mechanical deformation and obtain the optimal design parameters of the DPS. By rationally arranging the placement of sensitive grids to eliminate the discrepancy of relative resistance changes within four arms of the Wheatstone full-bridge circuit, the appropriate GF and high temperature insensitivity are simultaneously achieved. The blood pressure sensor with the DPS is then fabricated and characterized experimentally, which demonstrates an appropriate GF (ΔU/U0)/P = 3.56 × 10−5 kPa−1 and low temperature coefficient of voltage (ΔU/U0)/ΔT = 3.4 × 10−7 °C−1. The developed mechanical structure design offers valuable insights for other resistive pressure sensors to improve the GF and temperature insensitivity.

Design of a serious game learning mechanism for the implementation of ISO 22000:2018 in the swallow’s nest industry

Design of a serious game learning mechanism for the implementation of ISO 22000:2018 in the swallow’s nest industry

Design and Analysis of Cybersecurity Information Sharing Mechanism Between Computer Security Incident Response Teams (CSIRT) in Indonesia on Blockchain Technology Through Hyperledger Composer and Interplanetary File System (IPFS)

Sharing cybersecurity information among the Computer Security Incident Response Team (CSIRT) is a crucial step in enhancing organizational cybersecurity. However, a primary challenge faced is the lack of trust among users regarding the confidentiality, integrity, and availability of shared information. This study proposes a new approach by designing a mechanism for sharing cybersecurity information among CSIRTs in Indonesia on blockchain technology using Hyperledger Composer. This approach offers an innovative solution by leveraging the advantages of blockchain technology. Through this approach, cybersecurity information can be shared in a decentralized manner, overcoming the weaknesses of centralized systems, and enhancing overall information security. Another advantage of blockchain technology is its high performance and scalability, enabling increased speed, and user capacity in the process of sharing information. By implementing a blockchain-based mechanism for sharing cybersecurity information, this research aims to ensure crucial aspects of information security, namely confidentiality, integrity, and availability. The contribution of this study is not only in enhancing organizational cybersecurity but also in providing an innovative solution to practical challenges in sharing cybersecurity information among CSIRTs.

Design and thermal simulation of the front-end module for STARLIGHT

This paper presents a front-end module emulator for SemiconducTor Array detectoR with Large dynamIc ranGe and cHarge inTegrating readout (STARLIGHT), a versatile hybrid silicon pixel detector with a high frame rate (≥10kHz) and serving as the first charge-integrating pixel detector for XFEL in China. The detector is intended for operation in a vacuum environment, with the front-end module generating a thermal power of up to 5.443 mW/mm2, presenting a significant challenge for thermal management. To assess the thermal management capabilities of the mechanical and PCB designs for the project, a thermal emulator was developed to replicate the heat generated by the ASIC. This was particularly crucial during the early stages of the project when the ASIC was not yet available, achieved by placing copper wires on the PCB. Subsequent thermal simulations were conducted and compared with the results obtained from the thermal emulator. The comparison shows that the experimental results are very close to the thermal simulation results, validating the thermal performance of the STARLIGHT front-end modules. These endeavors not only provide validation but also offer valuable insights to ensure the thermal efficiency of the STARLIGHT front-end modules.

Design of 2-DOF Thrust vector control system for Rockets and Missiles

This paper outlines the development and implementation of a Thrust Vector Control (TVC) system tailored specifically for solid propellant rocket engines, aimed at enhancing the portability of hybrid and liquid propellant rocket systems. The proposed system ensures trajectory stability and rapid response to flight emergencies by effectively addressing external perturbations like wind. Key components are Gyroscopic (GYRO) sensors, good micro-controller, and Servo motors, collectively referred to as Thrust vectoring components, which dynamically adjust thrust direction opposite to the rocket's trajectory to maintain stability. Drawing from an extensive literature review analyzing existing TVC system designs, with a focus on thrust characteristics and engine combustion timings, the design integrates considerations of geometric properties, kinematics, forces, energy requirements, safety, cost, and control methods, aligning with both mechanical and avionic design principles. The anticipated outcome is an advancement in rocket propulsion technology, characterized by improved angular speed control, trajectory linearity, and rapid response capabilities.

Fuzzy logic-based control for robot-guided strawberry harvesting: visual servoing and image segmentation approach

The concept of digital farming can help farmers increase their agricultural production yield. One of the technologies to support digital farming is robotics, which can be utilized to complete a redundant task efficiently for 24 hours. This paper presents a simple and effective harvesting robot that is applied to harvest a ripe strawberry. The mechanical and electrical design is kept simple to ensure it is reproducible. The input from a proximity sensor and image detection by a Pi camera is utilized by FLC (Fuzzy Logic Controller) to improve the effectiveness of the harvesting task. The image processing method in this study is image segmentation, which fits with the limited source of the microcontroller available in the market. The experiment included 60 times (20 times center, left, and right position) harvesting using the FLC algorithm and 60 times without FLC to show the effectiveness of the proposed method. From 60 experiments without an FLC experiment, there is an 80% hit rate for strawberries positioned in the middle of an image plane and 55% for left and right strawberries. From 60 times of FLC experiment, 95% hit rate for strawberries positioned in the middle of an image plane, 80% for left and right strawberries. The average time required to finish the task without FLC for strawberries in the middle is 13.51 s, the left is 11.04 s, and the right is 17.28 s. While the average time required to finish the task with FLC for strawberry in the middle is 12.90 s, the left side is 11.71 s, and the right side is 10.93 s. This study is intended to show that simple designs can be helpful and affordable when applied to greenhouse farming in Indonesia.

Controlling a Quadcopter with Static Loads and Dynamic Wind Disturbances using a Fuzzy Inference System

Maneuverability, hover, and simple mechanical design are the advantages of quadcopters. However, because quadcopters are smaller and lighter, they are more susceptible to wind than manned aircraft. The winds that cause air accidents are divided into several categories, namely downburst, turbulent wind, wind shear, and wind vortices. Disturbances and uncertainties, such as wind gusts, can result in difficulties in executing a mission on an accurate flight path. Quadcopter resilience is an important topic for UAV. Especially if the quadcopter is in terrain that is difficult for humans to reach. Hence, the system is susceptible and experiences reduced stability. Controlling a quadcopter with a cube-shaped static load to withstand turbulent wind gusts in this research uses robust Fuzzy Inference System control and trajectory control using LQR with Command-Generator Tracking. The results achieved through fuzzy control can fortify the quadcopter against half of the overall turbulent wind gusts with an RMSE of 0.0546. In contrast with the LQR-CGT control, which still exhibits an RMSE of 0.0795.

Mechanical design and kinematic performance of an anthropomorphic shoulder rehabilitation exoskeleton

Shoulder rehabilitation exoskeleton is a mechanical device to assist stroke patients in rehabilitation training, remodeling patients' neurological function by strengthening the muscles and promoting the recovery of shoulder function. At present, there are problems such as insufficient degree of freedom (DOF), insufficient overall range of motion (ROM), presence of passive joints, lack of the support of scapulohumeral rhythm (SHR), and poor kinematic synergy with the shoulder. This paper designs a 5-DOF shoulder rehabilitation exoskeleton based on the anatomical structure of the human shoulder and its motion characteristics, takes the 2-DOF shoulder girdle mechanism and the 3-DOF ball and socket mechanism as the main body taking into account the ergonomic factors in design, which ensures the synergistic motion with the patient's shoulder and provides the patient with a wide ROM. After setting up the drive and control system, this paper completes the prototype of the exoskeleton, furthermore, this paper describes the range of motion and kinematic synergy test. ROM tests and kinematic synergy experiments are conducted to evaluate the kinematic performance of this shoulder exoskeleton. The experimental results indicate that the shoulder exoskeleton prototype offers a high level of kinematic synergy with the wearer throughout a broad ROM.

Reliability Optimization Design of Constrained Metamorphic Mechanism Based on the Augmented Assur Groups

Reliability Optimization Design of Constrained Metamorphic Mechanism Based on the Augmented Assur Groups

Design and control of the Six-DOF robotic manipulator

This paper presents the building process and simulation of a robotic manipulator. Robotic manipulators are used in various scenarios, such as industry and agriculture. It would be of particular interest to learn how to systematically design and control a manipulator to follow a planned trajectory. Hence, a CAD model is developed in this paper. There is a rough finite element analysis for two cases in this study, which could easily find out how the product reacts to real-world forces and vibration. In order to solve real-world problems safely and effectively, this effort intends to build the mechanical design of the manipulator by SOLIDWORKS and simulate trajectory tracking capability using MATLAB.

3D DESIGN OF A AUTOMOTIVE 5 SPEED SYNCHROMESH GEARBOX IN AUTODESK INVENTOR

The gearbox is a rotary assembly that provides speed and torque conversions from one rotary power supply (crankshaft) to another device (drive wheels) due to internal combustion engine limitations and also facilitates the shaft steering output.Autodesk Inventor is a computer aided design (CAD) application for creating 3D digital prototypes used in mechanical design, visualization, tooling creation and product simulation. It allows the user to create prototype products that accurately simulate the weight, stress, friction, driving loads, and many more properties of the products and their components in a simulated 3D environment.This paper contains all the graphic knowledge and operations required to create a 3D model of a manual gearbox by using the Autodesk Inventor software, and step by step, procedure for generating a 3D model of an synchromesh gearbox, starting from the initial calculus in Mathconnex.

Drag-Mitigating Dynamic Flight Path Design and Sensitivity Analysis for an Ultra-Long Tether Underwater Kite

Abstract This paper presents a computational study of an underwater kite operating in environments requiring tethers exceeding a kilometer in length, referred to herein as ultralong tether (ULT) applications. Leveraging a detailed dynamic model of the kite and tether, we study the relationship between path shape and tether drag at varying tether lengths in order to develop meaningful insights as to the operation of systems that require ultralong tethers in order to reach viable flow resources. An initial study of a ULT kite application operating in a uniform flow field is presented, demonstrating that with an appropriately designed flight path, the kite is able to suppress the motion of the majority of the tether in order to achieve an order of magnitude greater power output than can be achieved with a straight tether, which is the typical assumption used in a performance estimation. Tether drag mitigation is characterized through the use of a novel metric termed effective tether length, which characterizes the total length of tether engaged in drag production. It is shown that a high-performance path shape can reduce the effect of tether drag by over 50%. This performance is shown to be comparable to the multi-airborne wind energy system (MAWES) proposed by Leuthold et al. (2017, “Induction in Optimal Control of Multiple-Kite Airborne Wind Energy Systems,” IFAC-PapersOnLine, 50(1), pp. 153–158; 2018, “Operational Regions of a Multi-Kite Awe System,” 2018 European Control Conference (ECC), IEEE, Limassol, Cyprus, June 13–15, pp. 52–57), which suppresses tether motion through mechanical design rather than merely though careful path selection and control. This initial study in a uniform flow field is followed by two sensitivity studies: one that assesses performance in realistic environments where the flow magnitude is a function of altitude above the seabed and a second that assesses the impact of tether drag reduction techniques. It will be shown that by careful selection of path shape, site, and tether design, a single kite in a ULT marine application can achieve performance rivaling that of the MAWES without the extra required mechanical complexity.

Behaviour, finite element modelling and design of flanged cruciform section steel columns

A study into the mechanical behaviour and design of flanged cruciform section steel members subjected to axial compression is presented herein. The mechanical behaviour of flanged cruciform section columns is first described, with particular emphasis on the newly developed approach for determining the elastic local buckling load for full flanged cruciform cross-sections. Existing experimental data on flanged cruciform section steel columns collected from the literature are then employed to validate numerical models developed within the finite element package ABAQUS. A comprehensive parametric study is subsequently conducted that encompasses a broad spectrum of cross-sectional geometries and global slenderness values. The mechanical behaviour and ultimate resistance of flanged cruciform section columns are shown to be dependent on not only the global slenderness, but also on the ratio of the elastic torsional to flexural buckling loads. The existing experimental data alongside the numerical parametric study results are employed to evaluate the resistance predictions provided in the current Eurocode 3 design codes, revealing a high degree of conservatism. Finally, a new design approach for flanged cruciform section columns, suitable for incorporation into future revisions of Eurocode 3, is proposed which provides significantly improved accuracy and consistency in resistance predictions compared with the current provisions. A reliability analysis of the proposed design approach is conducted in accordance with the EN 1990 procedure, resulting in a recommended partial safety factor γM1=1.0.

Evaluation of Science Implementation in Mechanical Engineering Design Curriculum Class 2A State Polytechnic of Jakarta Pekalongan City Campus Academic Year 2023/2024

Evaluation of Science Implementation in Mechanical Engineering Design Curriculum Class 2A State Polytechnic of Jakarta Pekalongan City Campus Academic Year 2023/2024

Hybrid Integrated Wearable Patch for Brain EEG-fNIRS Monitoring.

Synchronous monitoring electroencephalogram (EEG) and functional near-infrared spectroscopy (fNIRS) have received significant attention in brain science research for their provision of more information on neuro-loop interactions. There is a need for an integrated hybrid EEG-fNIRS patch to synchronously monitor surface EEG and deep brain fNIRS signals. Here, we developed a hybrid EEG-fNIRS patch capable of acquiring high-quality, co-located EEG and fNIRS signals. This patch is wearable and provides easy cognition and emotion detection, while reducing the spatial interference and signal crosstalk by integration, which leads to high spatial-temporal correspondence and signal quality. The modular design of the EEG-fNIRS acquisition unit and optimized mechanical design enables the patch to obtain EEG and fNIRS signals at the same location and eliminates spatial interference. The EEG pre-amplifier on the electrode side effectively improves the acquisition of weak EEG signals and significantly reduces input noise to 0.9 μVrms, amplitude distortion to less than 2%, and frequency distortion to less than 1%. Detrending, motion correction algorithms, and band-pass filtering were used to remove physiological noise, baseline drift, and motion artifacts from the fNIRS signal. A high fNIRS source switching frequency configuration above 100 Hz improves crosstalk suppression between fNIRS and EEG signals. The Stroop task was carried out to verify its performance; the patch can acquire event-related potentials and hemodynamic information associated with cognition in the prefrontal area.

Trilateral Evolutionary Game Strategy for the Design Optimization of Engineering General Contracting Projects in the Chinese Context

The engineering general contracting mode is an advanced engineering transaction mode, and design optimization is one of the important driving forces for vigorously promoting the general contracting mode. The application proportion of the general contracting mode in infrastructure projects is not high, the number of successful projects is not large, and the implementation effect is not ideal. One of the main reasons is that the design optimization theory and practice of international standard general contracting projects cannot adapt to the general contracting projects in the Chinese context, making local general contracting projects face huge challenges such as low enthusiasm for design optimization from all parties and unsatisfactory design optimization effects. Therefore, under the premise of bounded rationality, when the owner adopts control methods of different intensities, an evolutionary game study on the selection of design optimization strategies between the design and construction parties is carried out, and stability control strategies are proposed through case experiments and simulations. The research results indicate the following: firstly, the design optimization of general contracting projects in the Chinese context is feasible, but it depends on the distribution ratio of benefits obtained from the design optimization. Compared with general civil construction general contracting projects, the design optimization allocation ratio of industrial construction general contracting projects is more significant; secondly, the mixed control method of strong control and weak control is the optimal choice for the owner of the general contracting project; and thirdly, there are multiple evolutionary stable points, and mechanism design or incentive measures should be used to guide owners to choose weak control strategies, while design and construction parties should choose their design optimization strategies. The research results provide a reference for owners to determine the proportion and scheme of design optimization allocation, and for construction parties to determine design optimization strategies.

Research on the Design of Aviation and Aerospace Hatch Door Mechanisms and Their Future Bionic Prospects

The design of the space hatch door mechanisms is crucial in the aerospace field, impacting not only durability and reliability but also the life safety of astronauts during space missions. This review extensively researches vehicle doors and hatches in civil and military systems across various environments, including land, sea, deep sea, aviation, aerospace, and extreme conditions. Specially, it focuses on the structural design of hatches and related mechanisms in civil aviation and military aerospace environments, such as opening and closing mechanisms, release mechanisms, locking mechanisms, sealing mechanisms, and the ergonomic design of door structures. The review highlights the integration of bionic design principles with hatch mechanisms to explore future solutions. By systematically examining these aeras, this review addresses the lack of comprehensive studies in previous reviews, which often overlook the interconnectivity and applicability of hatch mechanisms across different fields. The absence of such holistic reviews has led to fragmented knowledge and missed opportunities for cross-industry innovation. This review aims to fill these gaps by providing a wide range of design solutions and offering insights that can enhance the development of more reliable, efficient, and safe hatch mechanisms in aerospace and other high-stakes environments.