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2021 Seventh International Conference on Aerospace Science and Engineering (ICASE)最新文献

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Modern and Classical Pitch Control for Yak54 现代和经典的音高控制的Yak54
Pub Date : 2021-12-14 DOI: 10.1109/ICASE54940.2021.9904042
Danial Ahmed Mir
The present paper discusses the trade-offs between classical and modern controllers by designing a pitch hold autopilot for of yak54. Autopilots decreases the workload of pilots, making the flight more reliable and efficient. A pitch controller is initially designed using a classical technique, where root locus and Bode plots are studied to design a suitable feedback controller. Linear quadratic integrator (LQI), with a stable inner loop, is also synthesized to control the pitch attitude of yak54 using tools available in MATLAB. The classical and modern controllers are compared, and trade-offs of the designed controllers are discussed, supported with simulation results obtained via MATLAB.
本文通过设计yak54的俯仰保持自动驾驶仪,讨论了经典控制器与现代控制器之间的权衡。自动驾驶仪减少了飞行员的工作量,使飞行更加可靠和高效。采用经典的方法设计了一个俯仰控制器,研究了根轨迹和波德图,设计了一个合适的反馈控制器。利用MATLAB提供的工具,合成了具有稳定内环的线性二次积分器(LQI)来控制yak54的俯仰姿态。对经典控制器和现代控制器进行了比较,讨论了所设计控制器的优缺点,并给出了MATLAB仿真结果。
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引用次数: 0
Deep Learning Based Radar Target Classification Using Micro-Doppler Features 基于微多普勒特征的深度学习雷达目标分类
Pub Date : 2021-12-14 DOI: 10.1109/ICASE54940.2021.9904145
Ali Hanif, Muhammad Muaz
Demand for radar automatic target recognition is ever increasing owing to the extensive employment of radar sensors in urban scenarios and a drastic increase in the number of radar targets, especially drones and UAVs. Micro-Doppler signatures, resulting from the micro-motion dynamics of targets, have emerged as a key distinctive feature for radar automatic target recognition. This paper addresses the problem of radar target recognition based on deep learning and micro-Doppler signatures of targets. The choice of MobileNetV2 deep Convolutional Neural Network based classification on spectrogram images of the targets, has made the system more suitable for system implementation on embedded devices such as Raspberry Pi. Second important contribution of this paper is the augmentation of an extensive and diverse training dataset having five classes ultimately, for the testing of radar automatic target recognition, since few such datasets are available in the open literature. The dataset is developed using a W-band Frequency Modulated Continuous Wave radar. After training the model on the diverse training dataset, validation and test accuracies of 98.67% and 99% respectively, are achieved.
由于雷达传感器在城市场景中的广泛应用以及雷达目标数量的急剧增加,特别是无人机和无人机,对雷达自动目标识别的需求不断增加。微多普勒特征是由目标的微运动动态产生的,是雷达自动目标识别的一个重要特征。研究了基于深度学习和目标微多普勒特征的雷达目标识别问题。选择基于MobileNetV2深度卷积神经网络对目标的光谱图图像进行分类,使系统更适合于在树莓派等嵌入式设备上的系统实现。本文的第二个重要贡献是增加了一个广泛而多样的训练数据集,最终有五个类,用于雷达自动目标识别的测试,因为在公开文献中很少有这样的数据集。该数据集是使用w波段调频连续波雷达开发的。在不同的训练数据集上对模型进行训练,验证准确率达到98.67%,测试准确率达到99%。
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引用次数: 0
Design and Development of Audio Processing and Speech Recognition Algorithm 音频处理与语音识别算法的设计与开发
Pub Date : 2021-12-14 DOI: 10.1109/ICASE54940.2021.9904277
Muhammad Aitessam Ahmed
Speech recognition is the emerging technology in the field of artificial intelligence, as humans find easier to communicate and express their ideas via speech. Many state-of-the-art speech recognition systems have been designed in recent years after the innovation of GPUs, however, these cannot perform well in real-time on low-power processors. Therefore, this paper shows the development of an intelligent deep learning-based speech processing algorithm that was implemented on a quadcopter for simplifying the process of UAV control. The developed algorithm can also be used for other applications after integration with other systems such as automated data entry in ATMs and vending machines, home/office automation, speech-controlled vehicle navigation, and wheelchair operation. At first raw speech signals were converted to 2D spectrograms and then passed to the Convolutional Neural Network. ImageNet based pre-trained ResNet50 model was fine-tuned for the used audio dataset that required minimal feature and model design. After training using cloud GPU on Kaggle notebook, the model achieved the state of art results with 97.1% training accuracy and 96.45% validation accuracy. Then weights of the model were saved and algorithmic program was coded on python using Keras library backend with Tensorflow and an optimized algorithm was implemented on Jetson Nano for real-time transmission on the quadcopter. Speech commands were sent to the quadcopter for its real-time flights and it maneuvered successfully in a guided direction.
语音识别是人工智能领域的新兴技术,因为人类发现通过语音更容易沟通和表达自己的想法。在gpu创新之后,近年来设计了许多最先进的语音识别系统,然而,这些系统不能在低功耗处理器上实时表现良好。因此,本文展示了一种基于智能深度学习的语音处理算法的开发,并在四轴飞行器上实现,以简化无人机的控制过程。在与其他系统集成后,所开发的算法还可用于其他应用,例如自动取款机和自动售货机的自动数据输入,家庭/办公室自动化,语音控制车辆导航和轮椅操作。首先将原始语音信号转换为二维频谱图,然后传递给卷积神经网络。基于ImageNet的预训练的ResNet50模型对所使用的音频数据集进行了微调,需要最小的特征和模型设计。在Kaggle笔记本上使用云GPU进行训练后,该模型达到了97.1%的训练准确率和96.45%的验证准确率。利用Keras库后端和Tensorflow在python上编写算法程序,并在Jetson Nano上实现优化算法,实现四轴飞行器上的实时传输。语音命令被发送到四轴飞行器的实时飞行,它成功地在一个引导方向上操纵。
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引用次数: 0
Design and Development of a High Precision Thrust Measurement System 高精度推力测量系统的设计与研制
Pub Date : 2021-12-14 DOI: 10.1109/ICASE54940.2021.9904180
Muzamil Ali, Muhammad Dawood Bashir, G. Hussain, R. Ullah, M. Faisal
One of the fundamental steps in the applications of science and technology is the measurement of physical quantities involved in those applications. The measurement of these physical quantities is, however, not always trivial. In the applications such as the calibration of femto-satellites, and micro-plasma thrusters for future space exploration missions of NASA and other technological giants, where very precise attitude and position control is required, the measurement is a key issue to be addressed. One of such applications is a low-cost thrust measurement system. This paper presents the design and development of such a system, capable of successfully measuring the thrust of magnitude less than 20 μN by utilizing the principles of optical interference. The micro newtons pulse of a short duration is applied using an electromagnetic thruster setup on the tip of a pendulum. The pendulum subsequently performs the oscillations, and then an optical interferometer is used to precisely measure the deflection of the pendulum. The maximum deflection is then calibrated to obtain the applied thrust. The pendulum is designed based on optimal geometric parameters for maximum deflection of the pendulum tip for a response of thrust lasting for 100 milliseconds. For experimental validation, the interference signal is obtained in high resolution oscilloscope, which is subsequently processed to find the precise deflection of the pendulum and thus the precise thrust. The device successfully measures a minimum thrust of 18.44 μN. The precision is restricted due to environmental conditions and is not the limitation of the device itself.
科学技术应用的一个基本步骤是测量这些应用中涉及的物理量。然而,这些物理量的测量并不总是微不足道的。在美国国家航空航天局(NASA)等科技巨头未来太空探索任务的飞向卫星校准、微等离子体推进器等需要非常精确的姿态和位置控制的应用中,测量是需要解决的关键问题。其中一个应用是低成本的推力测量系统。本文介绍了利用光干涉原理成功测量20 μN以下推力的系统的设计和研制。短持续时间的微牛顿脉冲是用设置在钟摆尖端的电磁推力器施加的。摆随后进行振荡,然后用光学干涉仪精确测量摆的偏转。然后校准最大挠度以获得施加的推力。根据摆头最大挠度的最优几何参数设计摆头,使推力响应持续100毫秒。为了实验验证,在高分辨率示波器上获得干扰信号,然后对其进行处理,得到摆的精确挠度,从而得到精确推力。该装置成功地测量了18.44 μN的最小推力。精度受到环境条件的限制,而不是设备本身的限制。
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引用次数: 0
Detection of Thermal Fronts in the Arabian sea through SAR (Synthetic Aperture Radar) imagery 利用合成孔径雷达(SAR)图像探测阿拉伯海热锋
Pub Date : 2021-12-14 DOI: 10.1109/ICASE54940.2021.9904250
Nadia Jabeen, W. Qazi
During the summer (southwest) monsoon (SWM), the Arabian Sea’s surface circulation is clockwise, and heavy upwelling happens along the coasts of Oman and Somalia, resulting in high chlorophyll productivity which forms a thin biogenic slick over the sea surface. Satellite remote sensing observations of these features through optical and infrared wavelengths are confined to low resolution, and are observed to have data gaps due to cloud cover and dust storms. Space-borne Synthetic Aperture Radar (SAR) offers nearly all-weather day-night observation capabilities at a higher resolution. In this study, Advanced Land Observation Satellite (ALOS)-1/2 Phased Array L-band Synthetic Aperture Radar (PALSAR) datasets are used for the detection and extraction of physical oceanographic features of temperature fronts in the Arabian Sea during Southwest monsoon season (SWM). More than 100 HH-polarized ALOS PALSAR 1/2 images for the years 2007, 2010, 2014, and 2015 were acquired from JAXA during Southwest monsoon season. These datasets were pre-processed and Canny edge detection was implemented to extract temperature frontal features. For further analysis of the results, three length scales for the fronts are chosen by selecting length threshold according to the ocean dynamics of the study area. A few cases of the detected fronts are then validated against MODIS SST imagery. Validation shows that fronts of greater length are validated but some fronts of smaller length are not validated because of unavailability of data at their corresponding locations and also due to low spatial resolution of SST images.
在夏季(西南)季风(SWM)期间,阿拉伯海的表面环流是顺时针的,阿曼和索马里沿岸发生强烈的上升流,导致叶绿素生产力高,在海面上形成薄的生物浮油。通过光学和红外波长对这些特征进行的卫星遥感观测仅限于低分辨率,而且由于云层和沙尘暴的影响,观测到存在数据缺口。星载合成孔径雷达(SAR)以更高的分辨率提供几乎全天候的昼夜观测能力。本文利用先进陆地观测卫星(ALOS)-1/2相控阵l波段合成孔径雷达(PALSAR)数据集,对西南季风季节(SWM)阿拉伯海温度锋的物理海洋特征进行探测和提取。在西南季风季节,从JAXA获得了2007年、2010年、2014年和2015年的100多张hh偏振ALOS PALSAR 1/2图像。对这些数据集进行预处理,采用Canny边缘检测提取温度前沿特征。为了进一步分析研究结果,根据研究区海洋动态,通过选择长度阈值,选择了锋的三个长度尺度。然后根据MODIS海表温度图像对检测到的锋面进行验证。验证结果表明,长度较大的锋面得到了验证,而长度较小的锋面由于无法获得相应位置的数据以及海温图像的空间分辨率较低而没有得到验证。
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引用次数: 0
The Role of National Centers in Sustainable Development of Pakistan 国家中心在巴基斯坦可持续发展中的作用
Pub Date : 2021-12-14 DOI: 10.1109/ICASE54940.2021.9904199
Faaiz Ahmed Jeelani, N. Naqvi, U. Ahmed, D. Amin, Amir Faizan Malik
In order to facilitate the research and development paradigm of the country, national centers are envisioned and developed under the patronage of Higher Education Commission and Planning Commission of Pakistan. These centers are consortium of laboratories developed at various HEIs working in a targeted domain. Some of these centers have been in existence for the last three years and are near the completion of their project duration. To further establish the need of such centers in other targeted domains, it is reasonable to consider their contribution towards the sustainable development of the nation in context of United Nation Sustainable Development Goals. This study will be conducted using the qualitative as well as quantitative research methodologies on the data collected from semi-structured surveys in the domains of outreach, engagement, awareness, technical innovation, and human resource development. The survey is conducted for the targeted audience of the members affiliated with the subject centers and is then further analyzed using the Rochester’s Institute of Technology’s design thinking methodology. It is observed that the centers play a vital role in the outreach, engagement, and the awareness domains. Further work is required to be carried out in the additional domains to create long lasting impact in the context of UN SDGs.
为了促进国家的研究和发展模式,国家中心是在巴基斯坦高等教育委员会和计划委员会的赞助下设想和发展的。这些中心是由不同的高等教育机构在目标领域开发的实验室组成的联盟。其中一些中心已经存在了三年,目前已接近完成其项目期限。为了进一步确定这些中心在其他目标领域的需求,在联合国可持续发展目标的背景下考虑它们对国家可持续发展的贡献是合理的。本研究将采用定性和定量研究方法,对从外联、参与、意识、技术创新和人力资源开发领域的半结构化调查收集的数据进行研究。该调查是针对隶属于主题中心的成员的目标受众进行的,然后使用罗切斯特理工学院的设计思维方法进行进一步分析。可以观察到,这些中心在推广、参与和意识领域发挥着至关重要的作用。需要在其他领域开展进一步工作,以便在联合国可持续发展目标的背景下产生持久的影响。
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引用次数: 0
Role of Private-Public Partnerships in Creation of Space Awareness and Outreach in Pakistan 公私伙伴关系在巴基斯坦提高空间意识和外联方面的作用
Pub Date : 2021-12-14 DOI: 10.1109/ICASE54940.2021.9904083
Faaiz Ahmed Jeelani, N. Naqvi, U. Ahmed, Danial Amin, Amir Faizan Malik
Creating space awareness and outreach is a crucial step on the path to establishing a space country. Fundamental to the overall dynamics of a space nation is the requirement for a space-themed awareness and outreach campaign. Various sectors of society have a key role in promoting space awareness among the general population. Public-private collaborations have a crucial role in the creation of major impacts across several sectors. In this context, the influence of various public-private partnerships on the promotion of space awareness and education is examined. Evaluation of public-private collaborations is based on their contribution to the establishment of space awareness and outreach. Using qualitative and quantitative examination of the roles in the areas of planning, development, execution, and implementation, the function of public-private partnerships is evaluated. This function is contrasted with private-public collaborations in the energy industry, water sanitation, telecommunications, and education, among others. According to the studies undertaken, public-private partnerships have enormous potential for harvesting the benefits of space technology. There is significant opportunity for growth in this area, which may be achieved by forming more targeted and goal-oriented collaborations.
提高空间意识和拓展是建立空间国家道路上的关键一步。一个空间国家的整体动态的根本是要求以空间为主题的认识和宣传活动。社会各部门在提高一般民众的空间意识方面发挥着关键作用。公私合作在多个部门产生重大影响方面发挥着至关重要的作用。在这方面,审查了各种公私伙伴关系对促进空间认识和教育的影响。对公私合作的评价是基于它们对建立空间认识和推广的贡献。通过对规划、发展、执行和实施等领域的作用进行定性和定量检查,评估公私伙伴关系的功能。这一功能与能源工业、水卫生、电信和教育等领域的公私合作形成对比。根据所进行的研究,公私伙伴关系在获取空间技术的惠益方面具有巨大的潜力。这一领域有很大的增长机会,可以通过形成更有针对性和目标导向的合作来实现。
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引用次数: 0
Aerodynamic Shape Optimization of Doubly Offset Serpentine Diffuser using Response Surface Methodology 基于响应面法的双偏置蛇形扩散器气动外形优化
Pub Date : 2021-12-14 DOI: 10.1109/ICASE54940.2021.9904039
Zohaib Altaf, Arslan Ali, S. Salamat
Doubly offset serpentine diffusers have gained popularity in the compact design configurations of modern stealth fighters and UAVs with highly integrated propulsion systems into the airframe. In this research, the design space of a doubly offset serpentine diffuser is explored and the numerical optimization of its shape variables is achieved using response surface methodology to maximize total pressure recovery at the Aerodynamic Interface Plane between the engine and inlet. The stream-wise and transverse pressure gradients in the baseline diffuser are controlled using area distribution and centerline distribution equations respectively. The original geometry is perturbed using three control points distributed uniformly along the centerline and the central composite design has been used to select a pool of candidate designs. A steady-state flow solution has been achieved using governing Reynolds averaged Navier-Stokes equations applied through the general-purpose computational analysis tool ANSYS Fluent. A response surface is constructed out of the training data by fitting quadratic polynomials to the pressure recovery coefficients. The optimal diffuser design is found using a standard optimization algorithm from the response surface approximations. The optimized shape encompasses potential improvement in the total pressure recovery by 1.1% as compared to the baseline geometry. Results reveal that diffuser performance is a complex function of its geometric shape and any slight change in its shape variables may lead to significant performance degradation.
双偏置蛇形扩散器在现代隐形战斗机和具有高度集成推进系统的无人机的紧凑设计配置中得到了广泛的应用。本文对双偏置蛇形扩压器的设计空间进行了探索,并利用响应面法对其形状变量进行了数值优化,以最大化发动机与进气界面平面的总压恢复。采用面积分布方程和中心线分布方程分别控制基准扩散器的流向和横向压力梯度。利用沿中心线均匀分布的三个控制点对原始几何图形进行扰动,并采用中心复合设计来选择候选设计池。通过通用计算分析工具ANSYS Fluent,利用控制Reynolds平均Navier-Stokes方程获得了稳态流动解。通过对压力恢复系数进行二次多项式拟合,得到了训练数据的响应面。利用响应面近似的标准优化算法,找到了最优扩散器设计。与基准形状相比,优化后的形状可将总压采收率提高1.1%。结果表明,扩散器的性能是其几何形状的复杂函数,其形状变量的任何微小变化都可能导致显著的性能下降。
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引用次数: 0
Storm Time Ionospheric Variations from GNSS TEC and Swarm Satellites 来自GNSS TEC和Swarm卫星的风暴时间电离层变化
Pub Date : 2021-12-14 DOI: 10.1109/ICASE54940.2021.9904154
M. T. Khan, Munawar Shah
The geomagnetic storms cause severe threat to the performance of Global Navigation Satellite System (GNSS) and other satellites and it is also vulnerable to everything on the Earth. Similarly, ionosphere is dedicated to low down the arrival of different plasma parameters from the Sun, including CME (Coronal Mass Ejections) and solar flares. The aim of this work is to study the ionospheric responses to large geomagnetic storm (Kp > 8) throughout the whole world to study the different ionospheric variations. For this purpose, data from GNSS, and Swarm satellites have been studied for the storm time ionospheric responses. We have analyzed the storm during March 16–29, 2015, and during this storm, we have checked the different ionospheric parameters. The ionospheric variations studied in multiple stations of Asia, Africa, Australia, America and Europe by the analysis of TEC (Total Electron Content) over globe and ionospheric response through the analysis of Swarm satellites. In this work, an explanatory analysis is presented from GNSS and Swarm satellites data and found the possible storm time variations in ionosphere during the storm initial and main phases. Strong positive storm time variations found in stations of Asia (KIT3, SOLA, IISC), Africa (AREQ, YKRO, NKLG) and, America (CHPI, IQQE, RIOP) continents, respectively. This analysis can aid to correct the ionospheric scintillations during geomagnetic storms of different intensities.
地磁风暴对全球卫星导航系统(GNSS)和其他卫星的性能造成严重威胁,对地球上的一切都很脆弱。类似地,电离层致力于降低来自太阳的不同等离子体参数的到来,包括CME(日冕物质抛射)和太阳耀斑。本研究的目的是研究全球电离层对大地磁风暴(Kp > 8)的响应,以研究电离层的不同变化。为此,研究了来自GNSS和Swarm卫星的风暴时间电离层响应数据。我们分析了2015年3月16日至29日期间的风暴,并在风暴期间检查了不同的电离层参数。利用全球总电子含量(TEC)分析研究了亚洲、非洲、澳大利亚、美洲和欧洲多个站的电离层变化,并通过Swarm卫星分析电离层响应。本文对GNSS和Swarm卫星数据进行了解释性分析,发现了电离层在风暴初始阶段和主要阶段可能出现的风暴时间变化。在亚洲(KIT3、SOLA、IISC)、非洲(AREQ、YKRO、NKLG)和美洲(CHPI、IQQE、RIOP)大陆台站分别发现了强正的风暴时间变化。这种分析有助于纠正不同强度地磁风暴期间的电离层闪烁现象。
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引用次数: 0
Modeling and Analysis of a Vibratory Bowl Feeder 振动碗式给料机的建模与分析
Pub Date : 2021-12-14 DOI: 10.1109/ICASE54940.2021.9904038
Sadia Azhar, Syed Irtiza Ali Shah
Vibratory bowl feeders are required in industrial automation for the correct orientation of feed parts. These are considered to be efficient machines that are cheap and effective. The biggest disadvantage of the traditional vibratory bowl feeder is its inability to adapt to new designs, shapes, and orientations of the feed parts. Traditional vibratory bowl feeders are very inflexible and can work with only one orientation of the part. Although vibratory bowl feeders are considered to be traditional devices, these are now very much modernized and have adapted to diversified industrial needs. Robotic arms are also often used along with the cameras to orient the parts. However, with the employment of robots comes a high cost, extensive maintenance requirements, and complexity in the assembly line. So a viable solution is to use the best features of both machines, i.e. while keeping the cheap effective, and efficient qualities of a traditional vibratory bowl feeder, alter it to adapt to the changing part shapes and assembly lines. By doing so we can use the same vibratory bowl feeder for various orientations of components and in various assembly lines. This would eliminate the need for redesigning the vibratory bowl feeder with the orientation of each component, with which the assembly line is not only expensive but also time-consuming. By using this technique, we can orient almost any part, which is being fed to the feeder with the traditional vibratory feeder, without the use of fancy equipment or robots, just by altering and modernizing the traditional vibratory feeder. This would make the traditional vibratory bowl feeder, a device that is very flexible and can adapt to the changing feed, solving many problems. We can thus alter an already available system, to become versatile and adaptable, in numerous assembly lines for different parts, with very little alteration to the already existing systems. This research analyses the response of a vibratory bowl feeder under no external force, step input, and a sinusoidal input. The vibratory bowl feeder is modeled as a simple two degrees of freedom spring-mass-damper system and observed under the given inputs. The system is modeled as a case of base excitation, which is the case of a vibratory bowl feeder, as the input is applied to the system by the base. The results are validated by response graphs, which show the behavior and motion of the system under a specific input. Optimization suggestions are given by analyzing the results and behavior of the system.
在工业自动化中需要振动碗式给料机来实现给料部件的正确定位。这些被认为是高效的机器,既便宜又有效。传统的振动碗式给料机最大的缺点是它不能适应新的设计、形状和喂料部件的方向。传统的振动碗式给料机非常不灵活,只能在零件的一个方向上工作。虽然振动碗式给料机被认为是传统的设备,但这些设备现在非常现代化,并适应了多样化的工业需求。机械臂也经常与相机一起使用,以确定零件的方向。然而,随着机器人的使用,随之而来的是高成本、广泛的维护要求和装配线的复杂性。因此,一个可行的解决方案是利用这两种机器的最佳特性,即在保持传统振动碗式给料机的廉价、有效和高效品质的同时,对其进行改造,以适应不断变化的零件形状和装配线。通过这样做,我们可以使用相同的振动碗式给料机的不同方向的组件和不同的装配线。这将消除根据每个组件的方向重新设计振动碗式给料机的需要,这样的装配线不仅昂贵而且耗时。通过使用这种技术,我们可以定位几乎任何部分,这是喂料器与传统的振动,无需使用花哨的设备或机器人,只是通过改变和现代化的传统振动给料机。这将使传统的振动碗式给料机,一种非常灵活的装置,可以适应不断变化的饲料,解决许多问题。因此,我们可以改变一个已经可用的系统,使其在许多不同部件的装配线上变得通用和适应性强,而对现有系统的改变很少。研究了无外力、阶跃输入和正弦输入三种情况下的振动碗式给料机响应。将振动钵式给料机建模为一个简单的二自由度弹簧-质量-阻尼系统,并在给定输入条件下进行了观察。该系统建模为基座激励的情况,即振动钵式给料机的情况,因为输入由基座施加到系统中。通过响应图验证了结果,响应图显示了系统在特定输入下的行为和运动。通过对实验结果和系统行为的分析,提出了优化建议。
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引用次数: 0
期刊
2021 Seventh International Conference on Aerospace Science and Engineering (ICASE)
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