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Prime number-based multistep measurement for separation of roundness errors 基于质数的多步测量法分离圆度误差
IF 2 4区 工程技术 Q3 ENGINEERING, MECHANICAL Pub Date : 2024-08-28 DOI: 10.1177/09544062241270507
Tsung-Han Hsieh, Ming-Xian Lin
Roundness measurement is critical in manufacturing, as it ensures that products conform to precise design specifications. However, traditional multistep measurements for roundness error separation are time-consuming and limited in their ability to separate specific Fourier components. In this study, we propose a novel combined multistep measurement method with prime numbers that overcomes these limitations. We demonstrate this method through three experimental cases, achieving high levels of Fourier components in error separation with a limited number of measurements. Our method combines two ( p and q) or three ( p, q, and r) steps of prime numbers to achieve high levels of Fourier components for error separation, compared to traditional multistep measurements that require more steps. In the first experimental case, we use a 2-step and 5-step measurement to achieve traditional multistep measurement in ten steps. In the second case, we use 3-step and 5-step measurements, and in the third, we combine the 2-step, 3-step, and 5-step measurements. We achieve roundness deviations (RONt) of 12.7, 7.8, and 9.9 nm, respectively, and maximum En-values of 0.8, 0.8, and 0.7, respectively. Our proposed combined multistep measurement method using prime numbers has practical applications in manufacturing, as it reduces the time and resources required for roundness error separation while achieving a higher level of Fourier components. Our results demonstrate the effectiveness of our method and its potential to revolutionize roundness measurement in industry.
圆度测量在制造业中至关重要,因为它能确保产品符合精确的设计规范。然而,用于分离圆度误差的传统多步测量法不仅耗时,而且在分离特定傅立叶成分方面能力有限。在本研究中,我们提出了一种新颖的质数多步组合测量方法,克服了这些局限性。我们通过三个实验案例演示了这种方法,在有限的测量次数下实现了高水平的傅立叶分量误差分离。与需要更多步骤的传统多步骤测量法相比,我们的方法结合了质数的两个(p 和 q)或三个(p、q 和 r)步骤,实现了高水平的误差分离傅里叶分量。在第一个实验案例中,我们使用 2 步和 5 步测量法,在十步内实现传统的多步测量法。在第二种情况下,我们使用 3 步和 5 步测量法,而在第三种情况下,我们将 2 步、3 步和 5 步测量法结合起来。我们的圆度偏差 (RONt) 分别为 12.7、7.8 和 9.9 nm,最大 En 值分别为 0.8、0.8 和 0.7。我们提出的使用质数的组合式多步骤测量方法在制造领域具有实际应用价值,因为它既减少了圆度误差分离所需的时间和资源,又实现了更高水平的傅立叶分量。我们的研究结果证明了我们方法的有效性及其在工业圆度测量领域带来革命性变化的潜力。
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引用次数: 0
Microstructural and wear properties of iron slag reinforced aluminum alloy (LM30) based composite prepared through a stir casting method 搅拌铸造法制备的铁渣强化铝合金(LM30)基复合材料的微观结构和磨损性能
IF 2 4区 工程技术 Q3 ENGINEERING, MECHANICAL Pub Date : 2024-08-28 DOI: 10.1177/09544062241274862
Harvir Singh, Aayush Gupta
Aluminum alloys are widely used in various industries due to their as low density, high strength-to-weight ratio, and good corrosion resistance. However, their wear resistance is often inadequate for certain applications. Utilization of industrial waste materials, such as iron slag, as reinforcement in aluminum alloy matrix composites offers a sustainable approach to material development and waste management. The utilization of industrial waste materials for aluminum alloy matrix composite fabrication offers a waste utilization to material development. The loading of this reinforcement varied from 0 to 15 wt.% and different particle size range (220-140, 140-70, and 70-0 µm). A microscopic analysis indicated that the iron slag particles are spread uniformly inside the metallic matrix. There is also a reduction in the size of primary silicon, as well as morphological changes (acicular to globular shape). The wear behavior was calculated using a pin-on-disk wear set up in accordance with ASTM G99 standard. The composites were employed to dry sliding wear test under various operating conditions such as applied pressure (0.2–1.4 MPa), and sliding distance (0–3000 m). The 15F composite outperformed all other composite samples in terms of wear rate under all working conditions. When compared to the base alloy, it demonstrated a remarkable 67% drop in steady state wear rate. The enhancements in wear performance for the 15F composite were attributed to the effects of Fe slag reinforcement. The inclusion of iron slag particles induced strong interfacial bonding between matrix and reinforcement particles improving the durability of the mechanical mixed layer developed during relative motion. Importantly, the wear rate parameters of the 15F composite were similar to those of the brake drum material used in commercial applications. This emphasizes the composite suitability for usage in a variety of automobile components.
铝合金密度低、强度重量比高、耐腐蚀性好,因此被广泛应用于各行各业。然而,它们的耐磨性往往不足以满足某些应用的需要。利用铁渣等工业废料作为铝合金基复合材料的增强材料,为材料开发和废物管理提供了一种可持续的方法。利用工业废料制造铝合金基复合材料为材料开发提供了一种废物利用方法。这种增强材料的负载量从 0 到 15 wt.%不等,粒度范围也不同(220-140、140-70 和 70-0 µm)。显微分析表明,铁渣颗粒均匀地分布在金属基体中。原生硅的尺寸也有所减小,形态也发生了变化(从针状变为球状)。根据 ASTM G99 标准,使用针盘磨损装置计算了磨损行为。在不同的操作条件下,如施加压力(0.2-1.4 兆帕)和滑动距离(0-3000 米),对复合材料进行了干滑动磨损测试。在所有工作条件下,15F 复合材料的磨损率均优于所有其他复合材料样品。与基合金相比,它的稳态磨损率显著下降了 67%。15F 复合材料磨损性能的提高归因于铁渣强化的效果。铁渣颗粒的加入使基体和增强颗粒之间形成了牢固的界面结合,提高了相对运动过程中形成的机械混合层的耐久性。重要的是,15F 复合材料的磨损率参数与商业应用中的制动鼓材料相似。这说明这种复合材料适用于各种汽车部件。
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引用次数: 0
Exact discrete-time stability analysis of multi-DOF haptic rendering: Impact of multi-rate, time-delay, and mechanical parameters 多多维触觉渲染的精确离散时间稳定性分析:多速率、时延和机械参数的影响
IF 2 4区 工程技术 Q3 ENGINEERING, MECHANICAL Pub Date : 2024-08-27 DOI: 10.1177/09544062241271627
Suhail Ganiny, Majid H Koul, Babar Ahmad
Previous studies on the stability analysis of haptic devices have predominantly focused on single-DOF devices, thereby limiting attention to multi-DOF devices, particularly those employing multi-rate sampling schemes. In this paper, we introduce a formulation for the coupled dynamics between the haptic device and the virtual environment for a multi-DOF haptic device controlled using a dual-rate sampling scheme. Subsequently, we analyze its stability through the application of a dynamic decoupling strategy within an exact discrete-time state-space framework while the device is engaged in rendering a virtual wall along one of its operational space coordinates. Furthermore, we explore how the combined influence of the dual-rate sampling approach, time delay, and the mechanical design affects the stability boundaries of the multi-DOF haptic device at a fixed workspace location as well as within the entire usable workspace. Additionally, we utilize a model-order reduction (MOR) framework to simplify the determination of the device’s stability limits, irrespective of the specific combinations of time delay and sampling rates employed.
以往对触觉设备稳定性分析的研究主要集中在单多维设备上,从而限制了对多多维设备的关注,尤其是那些采用多速率采样方案的设备。在本文中,我们为使用双速率采样方案控制的多 DOF 触觉设备引入了触觉设备与虚拟环境之间的耦合动力学公式。随后,我们通过在精确离散时间状态空间框架内应用动态解耦策略来分析其稳定性,同时该设备正沿着其一个操作空间坐标渲染虚拟墙。此外,我们还探讨了双速率采样方法、时间延迟和机械设计的综合影响如何在固定工作空间位置以及整个可用工作空间内影响多多维触觉设备的稳定性边界。此外,我们还利用模型阶次缩减(MOR)框架简化了设备稳定性极限的确定工作,而与所采用的时间延迟和采样率的具体组合无关。
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引用次数: 0
Adaptive super-twisting sliding mode control with neural network for electromechanical actuators based on friction compensation 基于摩擦补偿的机电致动器神经网络自适应超扭曲滑动模式控制
IF 2 4区 工程技术 Q3 ENGINEERING, MECHANICAL Pub Date : 2024-08-17 DOI: 10.1177/09544062241271676
Mengmeng Cao, Jian Hu, Jianyong Yao
Parameter uncertainties in the electromechanical actuator system and the obvious friction nonlinearity in the low speed stage will greatly deteriorate the control performance and even lead to system instability. In this paper, an adaptive super-twisting sliding mode controller with neural network (ASTSMNNC) is proposed for the electromechanical actuator system. The LuGre model is used to describe the nonlinear friction, a nonlinear dual-observer is designed to observe the LuGre model internal friction state, a parameter adaptive law is designed to estimate the unknown parameters existing in the system, the time-varying disturbance in the system is estimated by using the universal approximation property of neural network. The feedforward compensation technology is used to compensate the estimated errors of parameters and the observed error of disturbance, the second-order nonlinear sliding mode is designed to compensate the residual estimated errors of parameters and neural network, and the chattering phenomenon caused by the sliding mode control can be reduced at the same time. What’s more, the controller theoretically guarantees a prescribed tracking performance in the presence of various uncertainties, which is very important for high-accuracy control of motion systems. Lyapunov stability theorem is used to prove that the proposed controller can achieve the bounded stability of the system. Extensive comparative experimental results are obtained to verify the high-performance nature of the proposed control strategy.
机电执行器系统中的参数不确定性和低速阶段明显的摩擦非线性会大大降低控制性能,甚至导致系统不稳定。本文提出了一种针对机电执行器系统的神经网络自适应超扭曲滑模控制器(ASTSMNNC)。采用 LuGre 模型描述非线性摩擦,设计非线性双观测器观测 LuGre 模型内部摩擦状态,设计参数自适应法则估计系统中存在的未知参数,利用神经网络的普遍逼近特性估计系统中的时变扰动。采用前馈补偿技术补偿参数估计误差和扰动观测误差,设计二阶非线性滑模补偿参数估计误差和神经网络的残余误差,同时减少滑模控制引起的颤振现象。此外,该控制器从理论上保证了在各种不确定因素存在时的规定跟踪性能,这对于运动系统的高精度控制非常重要。利用 Lyapunov 稳定性定理证明了所提出的控制器可以实现系统的有界稳定性。大量对比实验结果验证了所提控制策略的高性能特性。
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引用次数: 0
An efficient explicit dynamic formulation of a Stewart platform parallel robot via new formalism 通过新形式对斯图尔特平台并行机器人进行高效的显式动态表述
IF 2 4区 工程技术 Q3 ENGINEERING, MECHANICAL Pub Date : 2024-08-16 DOI: 10.1177/09544062241263767
Otman El Baji, Nabil Ben Said Amrani, Driss Sarsri
In this paper, an explicit dynamic model for the 6-DOF Stewart platform parallel manipulator is established using a new formulation. The main principle of this formulation is to provide the final form of dynamic models based on a direct and systematic procedure; in more detail, the analytical expression of each term due to the dynamic effects, that is, the system inertia tensor, centrifugal/Coriolis tensor and the environment forces are developed according to only the physical parameters of the system (i.e., mass, inertia tensor, position of the center of mass and geometrical parameters) and generalized coordinates without the need for any complicated intermediate calculations such as the potential, kinetic and acceleration energy development. In this approach, the parallel manipulator is first opened into six serial legs and a free platform. Next, the dynamic models of each sub-structure can be easily obtained based on the new formulation in their own local space. The Jacobian and Hessian matrices of the constraint equations, resulting from the closed-loop chains, are then used to combine the substructure dynamics. Finally, a detailed dynamics model of the entire robot with respect to the workspace or the actuation space is developed. After that, a simulation of the suggested methodology is investigated and analyzed in comparison to the more established dynamic modeling techniques provided in the literature; the efficiency and correctness of our approach are then verified. It is shown that our method requires a lower computational cost and even competes with the implicit form of dynamic models. Finally, a trajectory-tracking problem using model-based control is presented. It is shown that our approach can be totally and efficiently computed online without the need for symbolic form of equations of motion, which is highly challenging for parallel manipulators.
本文采用一种新公式建立了 6-DOF Stewart 平台并联机械手的显式动态模型。更详细地说,只需根据系统的物理参数(即质量、惯性张量、质心位置和几何参数)和广义坐标,就能建立动态效应引起的各项,即系统惯性张量、离心力/科里奥利力张量和环境力的分析表达式,而无需进行任何复杂的中间计算,如势能、动能和加速度能的建立。在这种方法中,首先将并联机械手分成六个串联支腿和一个自由平台。然后,根据新的计算公式,在各自的局部空间内轻松获得每个子结构的动态模型。然后,利用闭环链产生的约束方程的雅各布矩阵和赫塞斯矩阵来组合子结构动力学。最后,针对工作空间或执行空间建立整个机器人的详细动力学模型。之后,对所建议的方法进行了仿真研究和分析,并与文献中提供的更成熟的动态建模技术进行了比较;然后验证了我们方法的效率和正确性。结果表明,我们的方法所需的计算成本更低,甚至可以与隐式动态模型相媲美。最后,介绍了一个使用基于模型控制的轨迹跟踪问题。结果表明,我们的方法可以完全高效地在线计算,而无需符号形式的运动方程,这对并行机械手来说极具挑战性。
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引用次数: 0
Analysis of exit delamination mechanism and critical axial force in ball helical milling of CFRP CFRP 球螺旋铣削过程中的出口分层机理和临界轴向力分析
IF 2 4区 工程技术 Q3 ENGINEERING, MECHANICAL Pub Date : 2024-08-16 DOI: 10.1177/09544062241270497
Haiyan Wang, Wanchun Yu, Yan Feng, Qingchao Wang
To determine the critical axial force of exit delamination in the ball helical milling (BHM) of CFRP, based on the classical laminar theory, the critical delamination is judged by the theory of virtual work displacement and the linear elastic fracture mechanics. The model that describes the crucial axial force in the BHM process is set up, given the anisotropy of CFRP and the specific shape of the ball end mill. The external force is a novel set as a quadratically distributed load dependent on the milling parameters in the model, and the relationship between the quantity of uncut remaining layers and the critical axial force is indicated. When the tool rotation speeds were 4000–8000 rpm, with 0.1–0.2 mm/rev axial feed and 0.02–0.04 mm/tooth tangential feed, helical milling experiments were carried out. The correlation among the milling parameters and axial force and exit delamination factor was investigated, taking into account the effect of tool wear. Comparing with the experimental data, combined with the exit delamination, the proposed model can well predict the critical axial force under different cutting conditions, and the milling parameters have a great impact on the axial forces and delamination. The hole-making delamination of the ball end mill is smaller compared to the end mill, and exit delamination of CFRP can be reduced in BHM technique.
为了确定 CFRP 球螺旋铣削(BHM)过程中出口分层的临界轴向力,在经典层流理论的基础上,利用虚功位移理论和线性弹性断裂力学对临界分层进行了判断。考虑到 CFRP 的各向异性和球头研磨机的特殊形状,建立了描述 BHM 过程中关键轴向力的模型。在模型中,外力被新设定为与铣削参数相关的二次分布载荷,并指出了未切削剩余层的数量与临界轴向力之间的关系。当刀具转速为 4000-8000 rpm,轴向进给量为 0.1-0.2 mm/rev,切向进给量为 0.02-0.04 mm/齿时,进行了螺旋铣削实验。考虑到刀具磨损的影响,研究了铣削参数与轴向力和出口分层系数之间的相关性。与实验数据相比,结合出口分层,所提出的模型能很好地预测不同切削条件下的临界轴向力,且铣削参数对轴向力和分层有很大影响。与立铣刀相比,球头铣刀的制孔分层更小,在 BHM 技术中可以减少 CFRP 的出口分层。
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引用次数: 0
Development of a novel quadruped hybrid wheeled-legged mobile robot with telescopic legs 开发新型带伸缩腿的四足混合轮腿移动机器人
IF 2 4区 工程技术 Q3 ENGINEERING, MECHANICAL Pub Date : 2024-08-16 DOI: 10.1177/09544062241271624
Shuaiby Mohamed, YoungWoo Im, HyeonSang Shin, Youngshik Kim, Buhyun Shin
This paper presents a novel design of a quadruped hybrid leg-wheel mobile robot comprising two DOFs (a prismatic joint and a revolute joint) for the legs and one rotational joint for the wheel. The study begins by detailing the design of the structure and mechanism of the proposed system. We created the dynamic model of the proposed robot using MATLAB Simscape Multibody. The legged mode gait is developed using three supporting legs and one transferring leg. We developed a walking algorithm for the quadruped robot that comprises six motion steps. The simulation and experimental results demonstrate that our proposed robot has the ability to successfully traverse both flat surfaces and rough terrain. The robot’s design also enables it to perform various modes of movement, including normal vertical and horizontal driving, rotation around the robot’s centre of gravity, rotation in a large arc, and walking on flat terrain.
本文介绍了一种新颖的四足腿轮混合移动机器人的设计,包括腿部的两个 DOF(一个棱柱关节和一个旋回关节)和轮子的一个旋转关节。本研究首先详细介绍了拟议系统的结构和机构设计。我们使用 MATLAB Simscape Multibody 创建了拟议机器人的动态模型。使用三条支撑腿和一条转移腿开发了腿模式步态。我们为四足机器人开发了一种包含六个运动步骤的行走算法。仿真和实验结果表明,我们提出的机器人既能在平坦表面上行走,也能在崎岖地形上行走。机器人的设计还使其能够执行各种运动模式,包括正常的垂直和水平行驶、围绕机器人重心旋转、大弧度旋转以及在平坦地形上行走。
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引用次数: 0
An experimental and optimization of heat transfer between two-disk systems 双盘系统间热传递的实验与优化
IF 2 4区 工程技术 Q3 ENGINEERING, MECHANICAL Pub Date : 2024-08-02 DOI: 10.1177/09544062241262660
Rakesh Kumar Yadu, Achhaibar Singh, Dinesh Kumar Singh
This research focuses on experimentally investigating and optimizing heat transfer between two parallel disks, a prevalent system extensively utilized in engineering devices and various machinery. Analyzing heat transfer in this configuration is of paramount interest to researchers and engineers. An experimental setup was built to explore heat transfer between two parallel disks. Local Nusselt number and average Nusselt number were calculated to analyze heat transfer characteristics. The study delved into the effects of vital parameters such as the gap ratio, Reynolds number, and heat flux on heat transfer between two parallel disks. The analysis revealed that the Nusselt number increases with an increase in the gap between two disks up to a certain level, beyond which an inverse effect is observed. Moreover, the Nusselt number demonstrates a positive correlation with the Reynolds number. An in-depth analysis of local and average Nusselt numbers indicated that heat flux initially has a positive effect, followed by an adverse effect after reaching a certain level. To ascertain the optimum solution, three different techniques were employed: Response Surface Method (RSM), Cuckoo Search Algorithm (CS), and Genetic Algorithm (GA). The predicted optimum values for the gap ratio, Reynolds number, and heat flux using GA, CS, and RSM were as follows: gap ratio (17.36, 17.36, and 17.36), Reynolds number (100, 100, and 98.2), and heat flux (689.36, 694.5, and 682.449), respectively. Correspondingly, the resulting average Nusselt numbers were projected to be 48.59, 48.36, and 48.5271. To validate the obtained results, experiments were conducted and compared with the predicted values. The comparison among these techniques indicated that all results fell within an acceptable margin of error. Specifically, RSM exhibited an error of 1.917%, CS showed an error of 0.962%, and GA displayed an error of 0.8931%.
这项研究的重点是通过实验研究和优化两个平行盘之间的传热,这是一种广泛应用于工程设备和各种机械的普遍系统。分析这种配置下的热传递是研究人员和工程师最感兴趣的问题。我们建立了一个实验装置来探索两个平行盘之间的热传递。通过计算局部努塞尔特数和平均努塞尔特数来分析传热特性。研究深入探讨了间隙比、雷诺数和热通量等重要参数对两个平行盘之间热传递的影响。分析结果表明,努塞尔特数随着两个盘之间间隙的增大而增大,直至达到一定程度,超过一定程度后会出现反向效应。此外,努塞尔特数与雷诺数呈正相关。对局部努塞尔特数和平均努塞尔特数的深入分析表明,热通量最初具有正效应,达到一定水平后会产生负效应。为了确定最佳解决方案,采用了三种不同的技术:响应面法(RSM)、布谷鸟搜索算法(CS)和遗传算法(GA)。采用 GA、CS 和 RSM 预测的间隙比、雷诺数和热通量的最佳值分别为:间隙比(17.36、17.36 和 17.36)、雷诺数(100、100 和 98.2)和热通量(689.36、694.5 和 682.449)。相应地,推算出的平均努塞尔特数分别为 48.59、48.36 和 48.5271。为了验证所获得的结果,进行了实验并与预测值进行了比较。这些技术之间的比较表明,所有结果都在可接受的误差范围内。具体来说,RSM 的误差为 1.917%,CS 的误差为 0.962%,GA 的误差为 0.8931%。
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引用次数: 0
Meshing analysis of mismatch toroidal worm gearing characterized by different basic parameters of hob and worm 以滚刀和蜗杆的不同基本参数为特征的错配环形蜗杆传动装置的啮合分析
IF 2 4区 工程技术 Q3 ENGINEERING, MECHANICAL Pub Date : 2024-08-02 DOI: 10.1177/09544062241259867
Yifei Chi, Da An, Yaping Zhao
Aiming at high error sensitivity and complicated worm gear manufacturing of the planar double enveloping toroidal worm drive, a new TP-H gearing which worm generates by a plane and the worm wheel generates by a straight profile hob is proposed. Firstly, a comprehensive and systematic meshing theory of this drive is established; A rigorous calculation method for the instantaneous contact point is proposed; A formula for calculating the eccentricity of the instantaneous contact ellipse based on the relative principal curvature is deduced, and it is suggested innovatively that the eccentricity can be used as the quantitative index for describing the degree of mismatch between teeth. Secondly, the selection and matching strategy of mismatched process parameters is given, and the contact behavior between tooth surfaces is simulated based on numerical examples, the results show that the novel transmission can achieve good point contact. The research will promote the in-depth development of the theory of mismatched meshing in toroidal worm drive, and explore the specific form of gearing with simple manufacturing, low error sensitivity, and considerable meshing performance.
针对平面双包络环形蜗杆传动误差灵敏度高、蜗轮制造复杂等问题,提出了一种蜗杆由平面产生、蜗轮由直齿面滚刀产生的新型 TP-H 传动装置。首先,建立了该传动装置全面、系统的啮合理论,提出了严密的瞬时接触点计算方法,推导出基于相对主曲率的瞬时接触椭圆偏心率计算公式,并创新性地提出可将偏心率作为描述齿间不匹配程度的量化指标。其次,给出了错配工艺参数的选择和匹配策略,并基于数值实例模拟了齿面之间的接触行为,结果表明新型传动装置可以实现良好的点接触。该研究将推动环形蜗杆传动错配啮合理论的深入发展,并探索出制造简单、误差敏感性低、啮合性能可观的特殊齿轮传动形式。
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引用次数: 0
Design and analysis of a four-crease origami gripper (FCOG) 四褶皱折纸抓手(FCOG)的设计与分析
IF 2 4区 工程技术 Q3 ENGINEERING, MECHANICAL Pub Date : 2024-08-02 DOI: 10.1177/09544062241263759
Lifang Qiu, Shuyu Cui
In this paper, a Four-Crease Origami Gripper (FCOG) is designed. The kinematic model of the FCOG is derived. The correctness of the theoretical model is verified through experimental tests. To describe the performance of the FCOG, two parameters are defined, that is, capacity ratio and load ratio. The capacity ratio describes the configuration characteristics of the FCOG, which has been validated through experiments and analysis. The load ratio describes the load-bearing performance. The experiments show that the FCOG can meet the requirements of strength and load performance. Finally, the future potential applications of the FCOG are discussed.
本文设计了一种四褶皱折纸机械手(FCOG)。推导出了 FCOG 的运动学模型。通过实验测试验证了理论模型的正确性。为了描述 FCOG 的性能,定义了两个参数,即能力比和负载比。容积率描述了 FCOG 的配置特性,并通过实验和分析进行了验证。负载率描述的是承载性能。实验表明,FCOG 能够满足强度和负载性能的要求。最后,讨论了 FCOG 未来的潜在应用。
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引用次数: 0
期刊
Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science
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