Design and Simulation of a Novel Horizontal Sensitive Inertial Micro-Switch with Low G Value

2013 ◽  
Vol 336-338 ◽  
pp. 281-285
Author(s):  
Yong Liang Wang ◽  
Wen Guo Chen ◽  
Zhao Yu Wang ◽  
Gui Fu Ding ◽  
Xiao Lin Zhao
Keyword(s):  
Contact Time ◽  
Proof Mass ◽  
Quartz Substrate ◽  
Rebound Effect ◽  
Sine Wave ◽  
Special Design ◽  
Traditional Design ◽  
Fixed Electrode ◽  
G Value ◽  
Peak Value

A novel horizontal sensitive inertial micro-switch with low g value was proposed and simulated in ANSYS, and was fabricated on quartz substrate based on non-silicon surface micromaching technology. Due to this special design, the micro-switch has a very good horizontal unidirectional sensitivity. The contact effect is improved by a modification of the traditional design. The flexible contact between the proof mass electrode and fixed electrode prolongs the contact time and reduces the rebound effect. The contact time is about 100μs under a half-sine wave shock with a12g peak value.

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

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.

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

Micromachines ◽  
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.

Micromachined Snap-In Resonators

2012 ◽  
Vol 2012 (DPC) ◽  
pp. 001920-001935 ◽  
Author(s):  
Colin Stevens ◽  
Robert Dean ◽  
Chris Wilson
Keyword(s):  
Resonant Frequency ◽  
Proof Mass ◽  
Pressure Sensors ◽  
Mass System ◽  
Dc Voltage ◽  
Movable Electrode ◽  
Mems Resonators ◽  
Spring Force ◽  
In Series ◽  
Fixed Electrode

MEMS resonators have many applications, including micromachined gyroscopes, resonating pressure sensors and RF devices. Typically, MEMS resonators consist of a proof mass and suspension system that allows the proof mass motion in one or two directions. Micromachined actuators provide kinetic energy to the proof mass, usually at its resonant frequency. In the simplest resonators, the actuators are driven with an AC signal at or near the resonant frequency. In more complex resonators, the actuator-proof mass system is placed in an amplifier feedback circuit so that the electromechanical system self-resonates. MEMS parallel plate actuators (PPAs) are simple to realize, yet complex nonlinear variable capacitors. If a DC voltage is applied in attempt to move the proof mass greater than 1/3 of the electrode rest gap distance, the device becomes unstable and the electrodes snap into contact. A current limiting resistor is often placed in series with the PPA to limit short circuit current due to a snap-in event. Consider the effect of placing a large resistor, on the order on 10 meg-Ohms, in series with the PPA. Then apply a DC voltage across the resistor-PPA pair of sufficient voltage to cause snap-in. Once the electrostatic force (ES) exceeds the spring force (SF), the electrodes will accelerate toward each other. The capacitance between the electrodes swells as the separation distance shrinks. Since the large resistor limits the charging rate of the capacitor, the voltage across it drops. Once the SF exceeds the EF, the momentum of the movable electrode brings it into contact with the fixed electrode, discharging the capacitor. The movable electrode then accelerates away from the fixed electrode while the resistor slowly allows recharging. After recharging, the cycle repeats resulting in stable oscillation. This resonator requires only a DC power supply, a resistor and a MEMS PPA.

scholarly journals Kinetics and Thermodynamics Studies of Copper(II) Adsorption onto Activated Carbon Prepared from Salacca zalacca Peel

Molekul ◽  
2020 ◽  
Vol 15 (2) ◽  
pp. 63
Author(s):  
Dewi Yuanita Lestari ◽  
Endang Widjajanti Laksono
Keyword(s):  
Activated Carbon ◽  
Contact Time ◽  
Metal Ion ◽  
Adsorption Process ◽  
Biogenic Carbon ◽  
Adsorption Data ◽  
Batch Technique ◽  
Langmuir Isotherm Model ◽  
G Value ◽  
Highly Porous

Highly porous and stable materials, such as alumina, silica, carbon, zeolite, and bentonite,  are well known and have been used as metal ion adsorbents. However, the use of biogenic carbon as adsorbent is relatively rare. The adsorption of copper(II) onto activated carbon extracted from Salcaca zalacca peel was studied. The effect of initial copper concentration, contact time, and a series temperature was studied. Adsorption was carried out in a batch technique. The adsorption equilibrium was reached after 60 minutes of contact time. The adsorption data had a better fitting line for the Langmuir isotherm model. The Langergren and also Ho and Mc Kay equations were used to predict the adsorption kinetics. The adsorption process obeyed a second-order kinetics model. The Thermodynamic parameters were ∆H°= -42.4180 kJ/mol; ∆S°= -0.0843 kJ/mol; ∆G°<0. These values indicated that the adsorption was exothermic and spontaneous. The low ∆G° value revealed that the main mechanism controlling the adsorption process was physisorption.

Design and characterisation of an inertial microswitch with electrophoretic polymer–metal composite fixed electrode for extending contact time

2012 ◽  
Vol 7 (5) ◽  
pp. 501 ◽  
Author(s):  
Bin Zhu ◽  
Zhuoqing Yang ◽  
Wenguo Chen ◽  
Qifa Liu ◽  
Guifu Ding ◽  
...  
Keyword(s):  
Contact Time ◽  
Metal Composite ◽  
Polymer Metal ◽  
Fixed Electrode

Numerical Solution of Elas-Plastic Impact Load of Tube Column

2008 ◽  
Vol 33-37 ◽  
pp. 363-368
Author(s):  
Chun Yang Liu ◽  
Bing Xin Li ◽  
Jin San Ju ◽  
Xiu Gen Jiang ◽  
Xiao Chuan You
Keyword(s):  
Rigid Body ◽  
Contact Time ◽  
Impact Load ◽  
Local Buckling ◽  
Tube Model ◽  
Mass Ratio ◽  
The Difference ◽  
Reduction Effect ◽  
The Impact ◽  
Peak Value

The explicit numerical method is used to trace the impact procedure of the tube columns impacted by a rigid body. The bar and rectangle tube models are both used to simulate the tube column. The elastic and elas-plastic impact load with different mass ratio and impact speed are obtained. The calculation results show that: for elastic models, the bigger the mass ratio and the higher the rigid body speed, the bigger the peak value of elastic impact load; at the same time, the more obvious the reduction effect of local buckling of rectangle tube on the peak value of impact load and the longer the contact time of tube model; so the peak value of impact load of the rectangle tube is not proportional to the rigid body speed. The stress wave in the tube causes a little difference between the load curves of tube model and bar model. For elas-plastic models, the higher the rigid body speed and the smaller the mass ratio, the bigger the peak value of impact load and the longer the contact time. The higher the rigid body speed, the bigger the difference between elastic and elas-plastic impact load peak value due to the expanding of plasticity. Because of the effect of local buckling, the peak value of elas-plastic impact load of rectangle tube is always lower than that of bar.

First Successful Run of 17.5 Inch Hybrid Bit in ADNOC Onshore to Drill Deviated Section

2021 ◽  
Author(s):  
Asif M. Khan ◽  
Frederic Chiodini ◽  
Juma Al Shamsi ◽  
Munir Bashir ◽  
Aseel Mohammed ◽  
...  
Keyword(s):  
Case History ◽  
Service Provider ◽  
Systematic Approach ◽  
Main Element ◽  
Special Design ◽  
Rate Of Penetration ◽  
History Data ◽  
Traditional Design ◽  
Drilling Operations ◽  
Drilling Bit

Abstract In the onshore drilling operation the main objective is always finding ways to optimize cost and improve the efficiency of drilling operations. Among the various available option, one possibility was to drill 17.5" deviated section in one run through the interbedded formation, which cause high vibrations and risk of twist-off. This section previously was drilled with minimum 2-3 bit runs for a heavy casing design. This would definitely reduce the well duration and cost. The plan involved to drill 17.5" deviated section using rotary steerable system using hybrid bit technology. Recent advances in drilling bit design has proved to be very effective in drilling surface hole sections but are limited to drill vertical holes and require multiple runs to complete a section. Special design and cutting structure is required when it comes to drill deviated hole. One supplier has combined the traditional design and come up with hybrid bit structure to achieve this goal of drilling surface deviated hole in one run. This special hybrid bit, drilled successfully 17.5" deviated section in one run with enhanced ROP by 40% compared to previous wells. This saved additional trips to change bit and avoided any stuck pipe and twist off. This kind of strategy has helped to maximize average ROP of 64 ft/hr for the entire section. The main element in optimizing the performance of is the systematic approach towards the bit selection, hydraulics and mud parameters. Outcome of this optimization resulted in case history data which shows that this kind of hybrid bit technology can be used to drill deviated wellbore with better penetration rates, lesser washouts and longer on-bottom time. This technical paper describes the results of first well drilled by a service provider using hybrid bit technology with rotary steerable system in one run. This has resulted in increasing the rate of penetration for the 17.5" deviated top hole section. Applying this kind of hybrid bit technology has not only enhanced the ROP but also helped to save rig days and cost.

scholarly journals Biosorption of Heavy Metals by Oscillatoria Species

2019 ◽  
pp. 1-8 ◽  
Author(s):  
Maryam Lami Riskuwa-Shehu ◽  
Haruna Yahaya Ismail ◽  
Maimuna Sulaiman
Keyword(s):  
Heavy Metals ◽  
Contact Time ◽  
Research Laboratory ◽  
Anthropogenic Activities ◽  
Algal Species ◽  
Mean Value ◽  
Time Dependent ◽  
Dependent Manner ◽  
Lower Biomass ◽  
Peak Value

Background: Several anthropogenic activities have led to serious health and environmental problems as a result of releasing different contaminants in to the ecosystem including heavy metals. This called for search of possible methods that could be used to ameliorate the environment and biosorption was found to be promising. Aim: The potential of Oscillatoria sp. was investigated with a view to determining its suitability in the biosorption of Cr2+ and Pb2+. Place and duration of Study: The study was conducted at the Research Laboratory, Department of Microbiology, Usmanu Danfodiyo University Sokoto, between January and July, 2016. Methodology: Samples of the algal species were collected from an irrigation site at Kwalkwalawa area of Usmanu Danfodiyo University Sokoto. The samples were dried and powdered for biosorption studies. Biosorbents were prepared and used for sorption of heavy metals at different time and substrate concentration. Results: It was observed that Oscillatoria sp. biomass could adsorb appreciable amounts of the metals in a dose and contact time-dependent manner. At lower biomass doses, lower rates were recorded with a mean of 0.002 mg/g and increased to 0.1mg/g when 2 g and 5 g biomass were used respectively in both cases of the metals uptake. Based on contact time, Cr2+ uptake was initially slow with mean value of 0.002 mg/g for the first 50 minutes and rapidly increased to optimum at 60 minutes of contact time. For Pb2+ however, uptake was rapid with peak value of 0.1mg/g for the first 20 minutes. The uptake drastically decreased at 35 and 50 minutes and equilibrium was attained at 60 minutes of contact time. Conclusion: Oscillatoria sp. has the potentials of Cr2+ and Pb2+ uptake and thus suitable for biosorption of low heavy metals concentrations.

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