Resin Concrete Specimens Attenuation Characteristics Research

2011 ◽  
Vol 141 ◽  
pp. 478-482
Author(s):  
Hong Gang Ding ◽  
Ze Yu Weng ◽  
Hong Wu You ◽  
Bo Lu ◽  
Xue Zhe Tang
Keyword(s):  
Cast Iron ◽  
Machine Tool ◽  
Dynamic Characteristics ◽  
Manufacturing Process ◽  
Response Curve ◽  
Damping Ratio ◽  
Frequency Response Curve ◽  
Amplitude Frequency Response ◽  
Half Power ◽  
Attenuation Characteristics

This paper introduces a method of manufacturing process of resin concrete, made three tubular cast-iron specimens filled with resin concrete. This paper detected the amplitude-frequency response curve of specimens in experimental method, and calculated the damping ratio of specimens through half power bandwidth method. The damping ratio of specimens is compared. It provided a good reference for the design of the machine tool on the dynamic characteristics.

scholarly journals Vibrational Analysis of Composite Beam Embedded with Nitinol Shape Memory Alloy Wires

2018 ◽  
Vol 7 (3.4) ◽  
pp. 143
Author(s):  
Omer Muwafaq Mohmmed Ali ◽  
Rawaa Hamid Mohammed Al-Kalali ◽  
Ethar Mohamed Mahdi Mubarak
Keyword(s):  
Shape Memory Alloy ◽  
Shape Memory ◽  
Frequency Response ◽  
Response Curve ◽  
Natural Frequencies ◽  
Damping Ratio ◽  
Vibrational Analysis ◽  
Laminated Composite ◽  
Vibration Modes ◽  
Frequency Response Curve

In this paper, laminated composite materials were hybridized with fibers (E-glass) and shape memory alloy wires which considered a smart material. The effect of changing frequency on the (acceleration- frequency) response curve, the damping ratio of the vibration modes, the natural frequencies of the vibration mode, the effect of shape memory alloy wires number on the damping characteristics were studied. Hand lay-up technique was used to prepare the specimens, epoxy resin type was used as a matrix reinforced by fiber, E-glass. The specimens were manufactured by stacking 2 layers of fibers. Shape memory alloy, type Nitinol (nickel-titanium) having a diameter (1 and 2mm), was used to manufacture the specimens by embedding (1,2 and 3) wires into epoxy. Experimentally, the acceleration- frequency response curve was plotted for the vibration modes, this curve was used to measure the natural frequencies of the vibration modes and calculate the damping ratio of the vibration modes. ANSYS 15- APDL was used to determine the mode shape and find the natural frequencies of the vibration modes then compared with the experimental results. The results illustrated that, for all specimens increasing the natural frequency leads to decreasing the damping ratio. Increasing the number of shape memory alloy wires leads to increase the values of the damping ratio of the vibration modes and the natural frequencies of the vibration modes at room temperature. 

Structural investigation of steel-reinforced epoxy granite machine tool column by finite element analysis

2019 ◽  
Vol 233 (11) ◽  
pp. 2267-2279 ◽  
Author(s):  
Prabhu Raja Venugopal ◽  
M Kalayarasan ◽  
PR Thyla ◽  
PV Mohanram ◽  
Mahendrakumar Nataraj ◽  
...  
Keyword(s):  
Finite Element Analysis ◽  
Finite Element ◽  
Cast Iron ◽  
Machine Tool ◽  
Dynamic Characteristics ◽  
Element Model ◽  
Static Stiffness ◽  
Element Analysis ◽  
Static And Dynamic Characteristics ◽  
Machining Center

Higher damping with higher static stiffness is essential for improving the static and dynamic characteristics of machine tool structures. The structural vibration in conventional machine tools, which are generally made up of cast iron and cast steel, may lead to poor surface finish and the dimensional inaccuracy in the machined products. It leads to the investigation of alternative machine tool structural materials such as concrete, polymer concrete, and epoxy granite. Although epoxy granite has a better damping capacity, its structural stiffness (Young's modulus) is one-third as compared to cast iron. Therefore, the present work represents optimization of the structural design of the vertical machining center column by introducing various designs of steel reinforcement in the epoxy granite structure to improve its static and dynamic characteristics using experimental and numerical approaches. A finite element model of the existing cast iron vertical machining center column has been developed and validated against the experimental data obtained using modal analysis. Furthermore, finite element models for various epoxy granite column designs have been developed and compared with the static and dynamic characteristics of cast iron column. A total of nine design configurations for epoxy granite column with steel reinforcement are evolved and numerical investigations are carried out by finite element analysis. The proposed final configuration with standard steel sections has been modeled using finite element analysis for an equivalent static stiffness and natural frequencies of about 12–20% higher than cast iron structure. Therefore, the proposed finite element model of epoxy-granite-made vertical machining center column can be used as a viable alternative for the existing column in order to achieve higher structural damping, equivalent or higher static stiffness and, easy and environmental-friendly manufacturing process.

Static and dynamic behavior of steel-reinforced epoxy granite CNC lathe bed using finite element analysis

2020 ◽  
Vol 234 (4) ◽  
pp. 595-609
Author(s):  
Shanmugam Chinnuraj ◽  
PR Thyla ◽  
S Elango ◽  
Prabhu Raja Venugopal ◽  
PV Mohanram ◽  
...  
Keyword(s):  
Finite Element Analysis ◽  
Finite Element ◽  
Cast Iron ◽  
Machine Tool ◽  
Dynamic Characteristics ◽  
Torsional Rigidity ◽  
Element Model ◽  
Element Analysis ◽  
Cnc Lathe ◽  
Machine Tool Structures

Machine tools are used to manufacture components with desired size, shape, and surface finish. The accuracy of machining is influenced by stiffness, structural damping, and long-term dimensional stability of the machine tool structures. Components machined using such machines exhibit more dimensional variations because of the excessive vibration during machining at higher speeds. Compared to conventional materials like cast iron, stone-based polymer composites such as epoxy granite have been found to provide improved damping characteristics, by seven to ten folds, due to which they are being considered for machine tool structures as alternate materials. The stiffness of structures made of epoxy granite can be enhanced by reinforcing with structural steel. The current work highlights the design and analysis of different steel reinforcements in the lathe bed made of the epoxy granite composite to achieve equivalent stiffness to that of cast iron bed for improved static and dynamic performances of the CNC lathe. A finite element model of the existing the cast iron bed was developed to evaluate the static (torsional rigidity) and dynamic characteristics (natural frequency) and the results were validated using the experimental results. Then finite element models of five different steel reinforcement designs of the epoxy granite bed were developed, and their static and dynamic behaviors were compared with the cast iron bed through numerical simulation using finite element analysis. The proposed design (Design-5) of the epoxy granite bed is found to have an improvement in dynamic characteristics by 4–10% with improved stiffness and offers a mass reduction of 22% compared to the cast iron bed, hence it can be used for the manufacture of the CNC lathe bed and other machine tool structures for enhanced performance.

Torque distribution method based on vibration instability of PS-HEV transmission system

2020 ◽  
Vol 234 (14) ◽  
pp. 3491-3503
Author(s):  
Yingfeng Cai ◽  
Lei Dou ◽  
Donghai Hu ◽  
Long Chen ◽  
Dehua Shi ◽  
...  
Keyword(s):  
Dynamic Equation ◽  
Hybrid Electric Vehicle ◽  
Response Curve ◽  
Electromechanical Coupling ◽  
Transmission System ◽  
Frequency Response Curve ◽  
Torque Distribution ◽  
Nonlinear Dynamic Equation ◽  
Amplitude Frequency Response ◽  
Power Split

The power-split hybrid electric vehicle has multiple working modes, which can be switched to different working mode according to different working conditions. The main switching process involved in the vehicle driving is the switch from the pure electric mode to the hybrid driving mode. This paper studies the mode switching process involved in the power-split hybrid electric vehicle driving process, and a nonlinear dynamic equation of the electromechanical coupling of the corresponding transmission system is established. Then the multi-scale method is employed to solve the dynamic equation, and the amplitude-frequency response curve is drawn. According to the curve, the effects of load, mechanical input excitation of the engine and motor electromagnetic excitation on the electromechanical coupling torsional vibration of the transmission system are studied. The engine and motor torque distribution schemes are obtained by analyzing the amplitude-frequency response curve of the torsional vibration characteristics of the system. The analysis results show that the vibration instability phenomenon of the transmission system can be avoided by establishing the nonlinear dynamic equation of the transmission system, analyzing the vibration characteristics of the vibration system, and optimizing the torque distribution of a PS-HEV at different working modes.

Design and analysis of epoxy granite vertical machining centre base for improved static and dynamic characteristics

2019 ◽  
Vol 234 (3) ◽  
pp. 481-495 ◽  
Author(s):  
Prabhu Raja Venugopal ◽  
P Dhanabal ◽  
PR Thyla ◽  
S Mohanraj ◽  
Mahendrakumar Nataraj ◽  
...  
Keyword(s):  
Cast Iron ◽  
Machine Tool ◽  
Dynamic Characteristics ◽  
Element Model ◽  
Numerical Approach ◽  
Structural Vibration ◽  
Polymer Concrete ◽  
Static Stiffness ◽  
Static And Dynamic Characteristics ◽  
Machine Tool Structures

The structural vibration in conventional machine tools which are generally made of cast iron may lead to poor surface finish of the machined components. This has led to the investigations on alternative materials for machine tool structures such as concrete, polymer concrete and epoxy granite which have higher damping properties but lesser Young's modulus. However, higher static stiffness with higher damping is essential for improving the static and dynamic characteristics of machine tool structures. Hence, this work focuses on replacing the vertical machining centre base made of cast iron with steel reinforced epoxy granite to improve the structural static stiffness. A finite element model of the above base is developed and validated against the experimental data obtained using modal analysis. The validated numerical approach is applied for investigating the seven progressive design configurations of base reinforced with steel. It is found that the epoxy granite base of Design configuration-7 with L-channels has significantly reduced the deformation by 56 and 36% considering milling and drilling operations, respectively, in comparison to cast iron base. Further, the natural frequencies of the above configuration are higher in all the modes (by more than 50%) under consideration than those of the existing cast iron structure. Therefore, the proposed configuration of base is a viable alternative for the existing base in order to achieve higher structural damping. The novelty of the present work is the design of epoxy granite vertical machining centre base using steel reinforcements to improve structural rigidity with ease of manufacturing.

Implementation of MQTT protocol based network architecture for smart factory

2021 ◽  
pp. 095440542110144
Author(s):  
Chia-Shin Yeh ◽  
Shang-Liang Chen ◽  
I-Ching Li
Keyword(s):  
Machine Tool ◽  
Gesture Recognition ◽  
Manufacturing Process ◽  
Network Architecture ◽  
Information Management System ◽  
Edge Computing ◽  
Smart Factory ◽  
Smart Manufacturing ◽  
Industrial Iot ◽  
Computing Module

The core concept of smart manufacturing is based on digitization to construct intelligent production and management in the manufacturing process. By digitizing the production process and connecting all levels from product design to service, the purpose of improving manufacturing efficiency, reducing production cost, enhancing product quality, and optimizing user experience can be achieved. To digitize the manufacturing process, IoT technology will have to be introduced into the manufacturing process to collect and analyze process information. However, one of the most important problems in building the industrial IoT (IIoT) environment is that different industrial network protocols are used for different equipment in factories. Therefore, the information in the manufacturing process may not be easily exchanged and obtained. To solve the above problem, a smart factory network architecture based on MQTT (MQ Telemetry Transport), IoT communication protocol, is proposed in this study, to construct a heterogeneous interface communication bridge between the machine tool, embedded device Raspberry Pi, and website. Finally, the system architecture is implemented and imported into the factory, and a smart manufacturing information management system is developed. The edge computing module is set up beside a three-axis machine tool, and a human-machine interface is built for the user controlling and monitoring. Users can also monitor the system through the dynamically updating website at any time and any place. The function of real-time gesture recognition based on image technology is developed and built on the edge computing module. The gesture recognition results can be transmitted to the machine controller through MQTT, and the machine will execute the corresponding action according to different gestures to achieve human-robot collaboration. The MQTT transmission architecture developed here is validated by the given edge computing application. It can serve as the basis for the construction of the IIoT environment, assist the traditional manufacturing industry to prepare for digitization, and accelerate the practice of smart manufacturing.

Research on Damping Properties of TiN Coating Prepared with Arc Ion Plating

2012 ◽  
Vol 184-185 ◽  
pp. 1167-1170
Author(s):  
Guang Yu Du ◽  
Zhen Tan ◽  
Kun Liu ◽  
Hao Chai ◽  
De Chun Ba
Keyword(s):  
Chemical Composition ◽  
Surface Morphology ◽  
Loss Factor ◽  
Steel Substrate ◽  
Damping Ratio ◽  
Energy Dispersive Spectrometer ◽  
Tin Coating ◽  
Arc Ion Plating ◽  
Ion Plating ◽  
Half Power

In this paper TiN coating was prepared on stainless steel substrate using arc ion plating technique. The coating samples’ phases, surface morphology, micro-determination chemical composition, loss factor and damping ratio were tested. The phases of TiN coating were determined by X-ray diffraction (XRD) technique. The surface morphology and chemical composition of the TiN coating were analyzed by scanning electron microscope (SEM) and Energy Dispersive Spectrometer (EDS), respectively. The damping performance of the samples was measured by hammering activation according half power bandwidth method. The loss factor or damping ratio of samples were obtained according frequency response curve. The results showed that damping performance of samples was considerably improved by TiN coatings.

Dynamics Characteristics for Contact Surface of Machine Tool

2014 ◽  
Vol 538 ◽  
pp. 91-94
Author(s):  
Wei Ping Luo
Keyword(s):  
Machine Tool ◽  
Dynamic Characteristics ◽  
Contact Surface ◽  
Dynamic Performance ◽  
Virtual Prototype ◽  
Prototype Model ◽  
Ansys Software ◽  
Dynamic Analyses ◽  
Contact Surfaces

A virtual prototype model of Machine Tool has been constructed by using the Pro/E software and the ANSYS software. Considering the effects of contact surfaces, dynamic analyses of Machine Tool are studied. The effects of contact surfaces on the dynamic characteristics of machine tool are studied. So that the purpose predicting and evaluating synthetically the machine tool dynamic performance without a physical sample can be achieved.

Analysis and Optimization of the Static and Dynamic Characteristics of Head Frame

2011 ◽  
Vol 418-420 ◽  
pp. 2055-2059 ◽  
Author(s):  
Yu Lin Wang ◽  
Na Jin ◽  
Kai Liao ◽  
Rui Jin Guo ◽  
Hu Tian Feng
Keyword(s):  
Machine Tool ◽  
Dynamic Characteristics ◽  
Maximum Stress ◽  
Dynamic Performance ◽  
Mode Shapes ◽  
Cnc Machine ◽  
Static And Dynamic Characteristics ◽  
Maximum Deformation ◽  
Improvement Measures ◽  
Optimal Measure

The head frame is a key component which plays a supportive and accommodative role in the spindle system of CNC machine tool. Improving the static and dynamic characteristics has profound significance to the development of machine tool and product performance. The simplified finite element modal is established with ANSYS to carry out the static and modal analysis. The results showed that the maximum deformation of the head frame was 0.0066mm, the maximum stress was 3.94Mpa, the deformation of most region was no more than 0.0007mm, which all verified that the head frame had a good stiffness and deforming resistance; several improvement measures for dynamic performance were also proposed by analyzing the mode shapes, and the 1st order natural frequency increased 7.33% while the head frame mass only increased 1.58% applying the optimal measure, which improved the dynamic characteristics of the head frame effectively.

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