On the Nonlinear Vibration Analysis of Ultra Precision Manufacturing Machines With Mode Coupling

2017 ◽  
Author(s):  
Mohammad Bukhari ◽  
Oumar Barry
Keyword(s):  
Internal Resonance ◽  
Vibration Analysis ◽  
Mode Coupling ◽  
Initial Conditions ◽  
Resonance Case ◽  
Precision Manufacturing ◽  
Resonant Case ◽  
Linear Behavior ◽  
Ultra Precision ◽  
Quadratic Stiffness

Nonlinear free undamped vibrations are investigated for ultra-precision manufacturing (UPM) machines with quadratic stiffness. The modes of the system are linearly coupled. The non-resonant case and the bounded internal resonance case are considered. The results of the non-resonant case indicate that the behavior of the system is the same as the linear behavior. However, for the internal resonance case, the results show that the amplitudes are coupled. The results also indicate that the nonlinear frequencies and amplitudes depend not only on the initial conditions, but also on the location of the isolators with respect to the center of gravity of the UPM.

On the Nonlinear Mode-Coupling in Ultra Precision Manufacturing Machines: Experimental and Analytical Analyses

2020 ◽  
Author(s):  
Sunit K. Gupta ◽  
Mohammad A. Bukhari ◽  
Oumar R. Barry ◽  
Chinedum E. Okwudire
Keyword(s):  
Internal Resonance ◽  
Mode Coupling ◽  
Vibration Isolation ◽  
Mathematical Formulation ◽  
Resonance Case ◽  
Precision Manufacturing ◽  
Resonant Case ◽  
Nonlinear Mode ◽  
Ultra Precision ◽  
Nonlinear Mode Coupling

Abstract Recent studies in passively-isolated systems have shown that mode coupling is desirable for best vibration suppression, thus refuting the long-standing rule of mode decoupling. However, these studies have ignored the non-linearities in the isolators. In this work, we consider stiffness nonlinearity from pneumatic isolators and study the nonlinear free undamped vibrations of a passively-isolated ultra-precision manufacturing (UPM) machine. Experimental analysis is conducted to guide the mathematical formulation. The system comprises linearly and nonlinearly coupled in-plane horizontal and rotational motion of the UPM machine with quadratic nonlinear stiffness from the isolators. We present closed-form expressions using the method of multiple scales for two cases viz. the non-resonant case and the bounded internal resonance case. We validate our theoretical findings through direct numerical simulations. For the non-resonant case, we show that the system behaves similar to a linear system. However, for the nearly internal resonance case, we demonstrate strong energy exchange between the modes stemming from nonlinear mode coupling. We further study the effect of nonlinear mode coupling on the vibration isolation performance and demonstrate that mode coupling is not always desirable.

Effects of Non-Proportional Damping on the Residual Vibrations of Mode-Coupled Ultra-Precision Manufacturing Machines

2014 ◽  
Author(s):  
Jihyun Lee ◽  
Chinedum Okwudire
Keyword(s):  
Mode Coupling ◽  
Low Frequency ◽  
Design Guidelines ◽  
Vibration Modes ◽  
Precision Manufacturing ◽  
Drastic Reduction ◽  
Coupling Vibration ◽  
Surface Finishes ◽  
Ultra Precision ◽  
Complex Parts

Ultra-precision manufacturing (UPM) machines are used to fabricate and measure complex parts having micrometer-level features and nanometer-level tolerances/surface finishes. Therefore, low-frequency residual vibrations that occur during the motion of the machines’ axes must be minimized. Recent work by the authors has revealed that coupling vibration modes of passively-isolated UPM machines can provide conditions for drastic reduction of residual vibrations vis-a-vis the recommended practice of modal decoupling. This paper presents an investigation into the effects of non-proportional (NP) damping on the conclusions reached in the authors’ prior work. With NP damping added, the conditions under which mode coupling is beneficial relative to decoupling are seen to remain largely the same. However, NP damping is shown to significantly influence the conditions under which the system’s response is most sensitive to mode coupling. Design guidelines for maximally exploiting the benefits of mode coupling are presented and demonstrated experimentally on a UPM machine.

scholarly journals Bactericidal surfaces: An emerging 21st-century ultra-precision manufacturing and materials puzzle

2021 ◽  
Vol 8 (2) ◽  
pp. 021303
Author(s):  
Mikel Larrañaga-Altuna ◽  
Alaitz Zabala ◽  
Iñigo Llavori ◽  
Oliver Pearce ◽  
Dinh T. Nguyen ◽  
...  
Keyword(s):  
21St Century ◽  
Precision Manufacturing ◽  
Ultra Precision

A Framework of a Continuous Injection Direct Rolling Process for Precision Manufacturing Plastic Plates with Patterned Microstructures

2014 ◽  
Vol 625 ◽  
pp. 489-495
Author(s):  
Ling Bao Kong ◽  
Ji Bin Li ◽  
Chi Fai Cheung ◽  
Yan Lou ◽  
Chang Sheng Wang ◽  
...  
Keyword(s):  
Research Work ◽  
Rolling Process ◽  
Plastic Plate ◽  
Precision Manufacturing ◽  
Injection Nozzle ◽  
Injection Process ◽  
Ultra Precision ◽  
Direct Rolling ◽  
Continuous Injection ◽  
Plastic Injection

This paper presents an integrated roller embossing process named Continuous Injection Direct Rolling (CIDR) process. The CIDR process is similar to Continue Casting Direct Rolling (CCDR) process for metal material. The process consists of Plastic Injection Module, Injection Nozzle, Precision Rolling Module, and Automatic Coiling Module. In the proposed CIDR process, the plastic plate with microstructured pattern is produced by the integrated injection and rolling process, which is different from the current rolling or plastic injection process. Some key technologies including injection nozzle design, roller design, roller coupling, and ultra-precision machining of rollers, are presented. An on-machine measurement method is also proposed and presented to avoid the incontinence and errors caused by disassembling the roller workpiece for off-line measurement. The results of the pilot study are also discussed. The research work provides an enabling solution for precision manufacturing plastic plate and film with microstructured patterns.

Topography simulation and vibration analysis of ultra-precision diamond flycutting micro V-groove

2011 ◽  
Vol 7 (5/6) ◽  
pp. 488
Author(s):  
Yong Liu ◽  
Ziqiang Yin ◽  
Shengyi Li ◽  
Yulie Wu ◽  
Yifan Dai
Keyword(s):  
Vibration Analysis ◽  
Ultra Precision

Ultra-precision manufacturing of silicon carbide mirrors with additive manufacturing

2021 ◽  
Author(s):  
Chao Xu ◽  
Hao Hu ◽  
Xiaoqiang Peng ◽  
Tao Lai ◽  
Jiahui Bao
Keyword(s):  
Silicon Carbide ◽  
Additive Manufacturing ◽  
Precision Manufacturing ◽  
Ultra Precision
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