The Design, Simulation and Fabrication of an Omnidirectional Inertial Switch with Rectangular Suspension Spring

An omnidirectional inertial switch with rectangular spring is proposed in this paper, and the prototype has been fabricated by surface micromachining technology. To evaluate the threshold consistency and stability of omnidirectional inertia switch, the stiffness of rectangular suspension springs is analyzed. The simulation result shows that the coupling stiffness of the rectangular spring suspension system in the non-sensitive direction is a little more than that in the sensitive direction, which indicated that the omnidirectional switching system’s stability is reinforced, attributed to the design of rectangular springs. The dynamic response simulation shows that the threshold of the omnidirectional inertial switch using the rectangular suspension spring has high consistency in the horizontal direction. The prototype of an inertial switch is fabricated and tested successfully. The testing results indicate even threshold distribution in the horizontal direction. The threshold acceleration of the designed inertial switch is about 58 g in the X direction and 37 g in the Z direction; the contact time is about 18 μs.

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A contact-enhanced MEMS inertial switch with electrostatic force assistance and multi-step pulling action for prolonging contact time

Microsystem Technologies ◽

10.1007/s00542-018-3881-7 ◽

2018 ◽

Vol 24 (7) ◽

pp. 3179-3191 ◽

Cited By ~ 6

Author(s):

Jian Li ◽

Yan Wang ◽

Yue Li ◽

Bo Fu ◽

Yunna Sun ◽

...

Keyword(s):

Contact Time ◽

Electrostatic Force ◽

Inertial Switch

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Modeling of Flexible Coupling to Connect Misaligned Flexible Rotors Supported on Ball Bearings

Volume 7A: Structures and Dynamics ◽

10.1115/gt2014-26891 ◽

2014 ◽

Cited By ~ 2

Author(s):

T. C. Gupta ◽

K. Gupta

Keyword(s):

Dynamic Response ◽

Stiffness Matrix ◽

Ball Bearing ◽

Radial Clearance ◽

Fe Model ◽

Ball Bearings ◽

Flexible Coupling ◽

Flexible Rotors ◽

Deep Groove ◽

Coupling Stiffness

Parallel or/and angular misalignment between rotors connected by flexible coupling causes deformation of coupling elements and rotor shafts both. The forces and moments from flexible coupling act on driver and driven rotors simultaneously and depend upon dynamic response of coupled rotor system. The authors’ aim in the present work is to propose a methodology to incorporate the coupling stiffness matrix and coupling loads into the finite element model of flexibly coupled flexible rotors supported on deep groove ball bearings. The coefficients of coupling stiffness matrix and coupling loads are nonlinear and depend upon the amount of parallel and angular misalignments. To segregate the effect of nonlinear stiffness of coupling on the dynamic response of the system, the stiffness of ball bearing is initially considered to be linear. Thereafter, ball bearing nonlinearities arising from radial clearance, Hertzian deformation of balls and races, and varying compliance effect are included into the FE model of the system. Considering different types of misalignments in succession and combination, the dynamic response is characterized by the presence of 1N, 2N and other super or sub harmonics. The misalignment in one plane is found to affect the dynamic response in both the orthogonal planes. Comparing to the stiffness of flexible coupling, the stiffness of ball bearing is of higher order and therefore, nonlinear coupling forces and moments have dominant influence on the dynamic response of the system.

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A MEMS inertial switch with electrostatic force assistance and multi-step pull-in for eliminating bounce and prolonging contact time

2017 19th International Conference on Solid-State Sensors, Actuators and Microsystems (TRANSDUCERS) ◽

10.1109/transducers.2017.7994018 ◽

2017 ◽

Author(s):

J. Li ◽

Y. Sun ◽

Y. Wang ◽

Z. Yang ◽

G. Ding ◽

...

Keyword(s):

Contact Time ◽

Electrostatic Force ◽

Inertial Switch

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Design and Dynamics Simulation of a Micromachined Inertial Switch with Polymer-Metal Composite Fixed Electrode for Flexible Contact

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.472-475.827 ◽

2012 ◽

Vol 472-475 ◽

pp. 827-830

Author(s):

Bin Zhu ◽

Zhuo Qing Yang ◽

Wen Guo Chen ◽

Qi Fa Liu ◽

Gui Fu Ding ◽

...

Keyword(s):

Contact Time ◽

Silicon Surface ◽

Dynamic Contact ◽

Sine Wave ◽

Dynamics Simulation ◽

Metal Composite ◽

Polymer Metal ◽

Fixed Electrode ◽

Inertial Switch ◽

Peak Value

A novel inertial micro-switch with polymer-metal composite fixed electrode has been designed based on non-silicon surface micromachining technology. The micro-switch can sense the applied accelerations from positive z-axis. It can realize a flexible contact between the electrodes, eliminate the bouncing phenomenon and prolong the contact time. The dynamic contact simulation of the micro-switch has been implemented under the half-sine wave shock with 80g peak value, and its vertical response time is about ~80μs.

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A laterally-driven micromachined inertial switch with a compliant cantilever beam as the stationary electrode for prolonging contact time

Journal of Micromechanics and Microengineering ◽

10.1088/0960-1317/24/6/065020 ◽

2014 ◽

Vol 24 (6) ◽

pp. 065020 ◽

Cited By ~ 9

Author(s):

Wenguo Chen ◽

Yan Wang ◽

Yongliang Wang ◽

Bin Zhu ◽

Guifu Ding ◽

...

Keyword(s):

Cantilever Beam ◽

Contact Time ◽

Stationary Electrode ◽

Inertial Switch

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Review article: Research on coupled vibration of multi-engine multi-gearbox marine gearing

Mechanical Sciences ◽

10.5194/ms-12-393-2021 ◽

2021 ◽

Vol 12 (1) ◽

pp. 393-404

Author(s):

Jingyi Gong ◽

Geng Liu ◽

Lan Liu ◽

Long Yang

Keyword(s):

Dynamic Response ◽

Dynamic Modeling ◽

Power Loss ◽

Dynamic Models ◽

Modeling Method ◽

Coupled Vibration ◽

Coupling Vibration ◽

Global Dynamic ◽

Theoretical Support ◽

Coupling Stiffness

Abstract. The type and working principle of multi-engine multi-gearbox gearing are introduced. The global dynamic modeling method, based on the generalized finite element theory, and the layered dynamic modeling method, based on the idea of whole first and then partial are proposed, and the dynamic models of three operation modes in the four engines with two shafts are established. The effects of coupling, rotation speed, configuration and power loss on the dynamic response of the system are studied by using the dynamic model. The research results show that the coupling vibration of multi-engine multi-gearbox gearing is obvious at low speed, and the coupling vibration weakens with the increase in speed. Reducing the coupling stiffness can weaken the coupling vibration of the system. The symmetrical structure of the transmission system has the same dynamic response at the symmetrical position. Meshing friction has little effect on the dynamic response of the system. The more power flowing through the cross-connect gearbox, the greater the system power loss. This research provides theoretical support for the low-vibration design of multi-engine multi-gearbox marine gearing and has a positive significance for understanding the coupled vibration characteristics of complex gear systems.

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Simulation and Experiment of a MEMS Omnidirectional Inertial Switch

Volume 10: Micro- and Nano-Systems Engineering and Packaging ◽

10.1115/imece2014-39737 ◽

2014 ◽

Author(s):

Y. Cao ◽

J. Wang ◽

Z. W. Xi ◽

W. R. Nie ◽

X. J. Wang ◽

...

Keyword(s):

Contact Time ◽

Threshold Value ◽

Shock Acceleration ◽

Test Device ◽

Fe Method ◽

Shock Test ◽

Simulation And Experiment ◽

Spring System ◽

Inertial Switch ◽

Mass Spring

A MEMS omnidirectional inertial switch was designed and fabricated based on non-silicon surface micromachining technology. The switch consists of mass-spring system, flexible radial electrodes and axial electrode. It has omnidirectional sensitivities in a half sphere. The modal analysis of the switch was performed. The system stiffness of the mass-spring system and the response displacement of the mass in all directions under the applied shock acceleration of 450g was obtained by using the FE method, as a result, the switch has good omnidirectional performance and small distributed threshold acceleration. The fabricated switches were tested by a shock test device. The results show that the threshold acceleration of the switches is within the range of 270g to 450g. As an acceleration exceeding the threshold value acting along the X-axis or Z-axis, the switch can be reliably closed and have a long contact time.

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Analysis of Closure Characteristics of a MEMS Omnidirectional Inertial Switch under Shock Loads

Shock and Vibration ◽

10.1155/2015/604047 ◽

2015 ◽

Vol 2015 ◽

pp. 1-10 ◽

Cited By ~ 1

Author(s):

Yun Cao ◽

Zhanwen Xi ◽

Jiong Wang ◽

Weirong Nie

Keyword(s):

Contact Time ◽

Theoretical Method ◽

Dynamic Contact ◽

Shock Acceleration ◽

Fe Method ◽

Prolonged Contact ◽

Spring System ◽

Inertial Switch ◽

Mass Spring ◽

Theoretical Results

A preliminary theoretical method for calculating contact time of a dual mass-spring system applied to shock acceleration was proposed based on the MEMS omnidirectional inertial switch. The influence of relevant parameters on the contact time was analyzed, and the theoretical results were in agreement with the simulation predictions. The theoretical method could provide the design of MEMS inertial switch for prolonged contact time. The system stiffness of the mass-spring system in all directions was obtained by using the FE method. Dynamic contact simulation results of contact time in typical directions under the applied shock acceleration indicate that the switch has a contact time within the range of 33 μs to 95 μs and has an enhanced contact effect with the dual mass-spring system in the MEMS inertial switch. The fabricated switches were tested by a shock test device. The results show that the switch can be reliably closed in all directions under the applied shock acceleration and has a long contact time, which is basically in accordance with the theoretical results.

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The Analysis of the Influence of Threshold on the Dynamic Contact Process of a Fabricated Vertically Driven MEMS Inertial Switch

Micromachines ◽

10.3390/mi10110791 ◽

2019 ◽

Vol 10 (11) ◽

pp. 791

Author(s):

Wenguo Chen ◽

Rui Wang ◽

Huiying Wang ◽

Dejian Kong ◽

Shulei Sun

Keyword(s):

Response Time ◽

Contact Time ◽

Contact Process ◽

Dynamic Contact ◽

Simply Supported Beam ◽

Simply Supported ◽

Analytical Simulation ◽

Fixed Electrode ◽

Inertial Switch ◽

G Value

In this work, to evaluate the influence of the threshold on the dynamic contact process, five models (number 1, 2, 3, 4, 5) with different thresholds were proposed and fabricated with surface micromachining technology. The contact time and response time were used to characterize the dynamic contact performance. The dynamic contact processes of the inertial switches with gradually increasing thresholds were researched using analytical, simulation, and experimental methods. The basic working principle analysis of the inertial switch shows that the contact time of the inertial switch with a low-g value can be extended by using a simply supported beam as the fixed electrode, but the high-G inertial needs more elasticity for fixed electrode. The simulation results indicate that the response time and contact time decrease with the increment in the designed threshold. Prototypes were tested using a dropping hammer system, and the test result indicates that the contact time of the inertial switch with a fixed electrode of the simply supported beam is about 15 and 5 μs when the threshold is about 280 and 580 g, respectively. Meanwhile, the contact time can be extended to 100 μs for the inertial switch using a spring as the fixed electrode when the threshold is about 280 and 580 g. These test results not only prove that the spring fixed electrode can effectively extend the contact time, but also prove that the style of the fixed electrode is the deciding factor affecting the contact time of the high-G inertial switch.

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