Design and Analysis of Surface Pressure Sensor for Colonoscopic Robot

2012 ◽  
Vol 468-471 ◽  
pp. 746-752
Author(s):  
Hai Yan Hu ◽  
Wei Da Li ◽  
Juan Li ◽  
Li Ning Sun
Keyword(s):  
Surface Pressure ◽  
Pressure Sensor ◽  
Least Squares Method ◽  
Pressure Sensors ◽  
Wheatstone Bridge ◽  
Element Analysis ◽  
Experiment System ◽  
Colon Wall ◽  
The Finite Element Analysis ◽  
Continuum Structure

The colonoscopic robot with continuum structure can offer enhanced environmental interaction by deforming to fit environmental constraints. In order to improve its perception ability and avoid perforation and other kickbacks, it is necessary to integrate pressure sensors into colonoscopic robot. A surface pressure sensor for the measure of contact pressure between colonoscopic robot and colon wall is designed. The sensor is made of aluminum and is 15.6mm in diameter and 3mm in width. It consists of external ring, internal ring, connection and two resistance strain gauge. The mechanical structure of the sensor is introduced. The mechanical characteristics is analyzed and simulated by the finite element analysis software ANSYS. The experiment system is built and the data is sampled through Wheatstone bridge. The data fitting is performed based on least squares method with Matlab software. The result shows that the surface pressure sensor has advantages of good linearity and accuracy. This study lays a foundation for the practical application of colonoscopic robot.

The Analysis and Study Based on MEMS Sensor

2011 ◽  
Vol 282-283 ◽  
pp. 271-274
Author(s):  
Yan Bing LI ◽  
Meng Yuan ◽  
Ji Yong Xu
Keyword(s):  
Pressure Sensor ◽  
Dynamic Properties ◽  
Wheatstone Bridge ◽  
Response Speed ◽  
Periodic Variation ◽  
Element Analysis ◽  
Structure Selection ◽  
Mems Sensor ◽  
The Finite Element Analysis ◽  
Selection Of

A kind of ultra micro pressure range MEMS pressure sensor is elaborated and analyzed in detail. The chip structure selection of pressure sensor is researched by the relative theory and the reasonable chip structure is designed in this paper. In order to design the Wheatstone bridge properly, we explore the width and length of the resistors on the membrane of the pressure sensor. At last, through the finite element analysis method, the relevant dynamic properties are analyzed for the sensor too. The dynamic response time is 3.2×10-5s. The response speed is fast and the sensor has many advantages under the periodic variation pressure.

Fabrication and Characteristics of Silicon Bridge Magnetic Sensor Based on Cantilever Beam

2014 ◽  
Vol 609-610 ◽  
pp. 1088-1093
Author(s):  
Lei Li ◽  
Xiao Feng Zhao ◽  
Yang Yu ◽  
Dian Zhong Wen ◽  
Jing Ya Cao ◽  
...  
Keyword(s):  
Magnetic Field ◽  
Cantilever Beam ◽  
Thin Film Transistors ◽  
Wheatstone Bridge ◽  
Magnetic Sensor ◽  
Element Analysis ◽  
Microelectromechanical System ◽  
The Finite Element Analysis ◽  
Mems Technology ◽  
Simulation Results

A silicon bridge magnetic sensor based on cantilever beam is presented in this paper. Thesensor is composed of the Wheatstone bridge that made up of nano-polysilicon thin-film transistors(TFTs) and a ferromagnetic magnet adhered to the free end of cantilever beam. Through building thesimulation model, the finite element analysis of the sensor is carried out by using ANSYS software.The results show that this sensor can realize the measurement to the external magnetic field. Accordingto the simulation results, fabrication and packaging of the sensor chip are achieved by using the microelectromechanical system (MEMS) technology. Experiment result shows that when the supply voltageis 3.0 V, the sensitivity of the sensor is 94 mV/T.

Design and Fabrication of Leadless Package Structure for Pressure Sensors

2021 ◽  
Author(s):  
Junwang Tian ◽  
Zhong Jin ◽  
Xin Tang ◽  
Wenxian Peng ◽  
Junfu Liu ◽  
...  
Keyword(s):  
Thermal Stress ◽  
High Temperature ◽  
Pressure Sensor ◽  
Silicone Oil ◽  
Pressure Sensors ◽  
Gold Wire ◽  
Electrical Signal ◽  
Back Side ◽  
Element Analysis ◽  
Silver Paste

Abstract Silicon piezoresistive pressure sensors can only operate below 125°C due to the leakage current of the PN junction. However, SOI high temperature pressure sensors use SiO2 for full dielectric isolation to solve this problem. At present, SOI high temperature pressure sensors mostly use lead bonding package structure, with gold wire to lead the electrical signal and silicone oil as the protection medium, but the working temperature of silicone oil is limited to about 150?. In this paper, the leadless package structure is designed by using pressure conduction on the back side of the chip and replacing the gold wire with conductive silver paste, and the materials and dimensions of the leadless package structure are determined. The reliability of the leadless package structure was verified by finite element analysis, and the results showed that the thermal stress caused by high and low temperature cycles in the leadless package is very small and does not affect the sensitivity of the pressure-sensitive chip. The size of the leadless package structure was optimized by Taguchi orthogonal method, and the maximum thermal stress was effectively reduced. Also, the key factors affecting the thermal stress of the leadless package in the package structure were identified by the variance number analysis method. The electrical signal conduction of the pressure sensor is achieved by a silver paste sintering process, and the data show that the sensitivity of the pressure sensor is 30.82 mV/MPa with a nonlinearity of less than 0.4% FS.

Surface Pressure Observations from Smartphones: A Potential Revolution for High-Resolution Weather Prediction?

2014 ◽  
Vol 95 (9) ◽  
pp. 1343-1349 ◽  
Author(s):  
Clifford F. Mass ◽  
Luke E. Madaus
Keyword(s):  
High Resolution ◽  
Real Time ◽  
Surface Pressure ◽  
Numerical Weather Prediction ◽  
Pressure Sensor ◽  
Weather Prediction ◽  
Pressure Sensors ◽  
Washington State ◽  
Sensor Technology ◽  
Eastern Washington

Millions of smartphones possess relatively accurate pressure sensors and the expectation is that these numbers will grow into the hundreds of millions globally during the next few years. The availability of millions of pressure observations each hour from smartphones has major implications for high-resolution numerical weather prediction. This paper reviews smartphone pressure-sensor technology, describes commercial efforts to collect the data in real time, examines the implications for mesoscale weather prediction, and provides an example of assimilating smartphone pressure observations for a strong convective event over eastern Washington State.

Development of Biocompatible MEMS Wireless Capacitive Pressure Sensor

2005 ◽  
Vol 2 (4) ◽  
pp. 287-296
Author(s):  
Shankaran Janardhanan ◽  
Joan. Z. Delalic ◽  
Jeffrey Catchmark ◽  
Dharanipal Saini
Keyword(s):  
Finite Element Analysis ◽  
Finite Element ◽  
Resonant Frequency ◽  
Pressure Sensor ◽  
Impedance Matching ◽  
Pressure Sensors ◽  
Important Variable ◽  
Bladder Pressure ◽  
Capacitive Pressure Sensor ◽  
Element Analysis

The objective of this research was to develop a wireless pressure sensor useful for monitoring bladder pressure. The wireless sensor consists of an active capacitive element and an inductor coil. The changes in pressure are related to the changes in the resonant frequency of the internal sensor. The existing pressure sensors have inductors formed on both sides of the substrate. The changes in internal capacitance of these sensors are related to the changes in pressure by impedance matching of the internal LC circuit. The deviation in bladder pressure is an important variable in evaluating the diseased state of the bladder. The inductor designed for this application is a spirally wound inductor fabricated adjacent to the capacitor. The external sensing uses equivalent changes in internal LC. The resonant frequency of the internal sensor is defined by the deformation of the plate, causing the plate to touch the dielectric on the fixed capacitive plate, which is reflected as changes in capacitance(C). The deformation of the plate has been modeled using Finite Element Analysis. The finite element analysis optimizes the dimensions of the design. Remote sensing is achieved through inductive coupling and the changes in pressure are determined. The device is tested for pressures ranging from 0–150 mmHg, bladder pressure. The RF Telemetry system has been modeled using Sonnet. The frequency range is between 100–670 MHz which is in compliance to that specified by Federal Communications Commission (FCC) regulations.

Influence of Pressure Fluctuation on Reflux Valve in a Self-Priming Pump With Outer Recirculation

2010 ◽  
Author(s):  
Hong Li ◽  
Zhenhua Shen ◽  
Jianrui Liu ◽  
Chao Wang
Keyword(s):  
Pressure Fluctuation ◽  
Pressure Difference ◽  
Pressure Fluctuations ◽  
Three Dimensional ◽  
Pressure Sensors ◽  
Element Analysis ◽  
Turbulence Flow ◽  
The Finite Element Analysis ◽  
Priming Process ◽  
The Stability

The pressure fluctuation caused by impeller-volute interaction is one of the factors which affect the stability of self-priming pump with outer recirculation. Based on the RNG k–ε turbulence model, three-dimensional unsteady turbulence flow in a self-priming pump was simulated in this paper. Pressure fluctuations were obtained at 26 monitor points distributed at eight sections of the volute and on the reflux valve, and the influence on the valve was analyzed. The CFD results show that the main frequency of monitor points is blade passing frequency, and the pressure difference between maximum and average is minimal at the fifth section, which is 1.3%∼2.4%. Using pressure sensors and LabVIEW system, the pressures at third, fifth and seventh sections were tested. The experimental results show that pressure fluctuation layouts are similar as those from CFD, and the pressure difference at the fifth section is 4%, also the minimum. The position also is found with minimal influence on reflux valve. Reflux hole should be placed at 200° ∼ 220° from the tongue along the direction of the impeller rotation. Further, according to the CFD results, the Finite Element Analysis (FEA) of the reflux valve was carried out. FEA shows that the valve can close the reflux hole completely after self-priming process, which gets a good hydraulic performance when the pump runs normally.

scholarly journals Ultra-Sensitive Flexible Pressure Sensor Based on Microstructured Electrode

Sensors ◽  
2020 ◽  
Vol 20 (2) ◽  
pp. 371 ◽  
Author(s):  
Mengmeng Li ◽  
Jiaming Liang ◽  
Xudong Wang ◽  
Min Zhang
Keyword(s):  
Pressure Sensor ◽  
Dielectric Layer ◽  
Pressure Sensors ◽  
High Sensitivity ◽  
Capacitive Sensor ◽  
Duty Ratio ◽  
Capacitive Pressure Sensor ◽  
Element Analysis ◽  
Sequential Coupling ◽  
Flexible Pressure Sensors

Flexible pressure sensors with a high sensitivity in the lower zone of a subtle-pressure regime has shown great potential in the fields of electronic skin, human–computer interaction, wearable devices, intelligent prosthesis, and medical health. Adding microstructures on the dielectric layer on a capacitive pressure sensor has become a common and effective approach to enhance the performance of flexible pressure sensors. Here, we propose a method to further dramatically increase the sensitivity by adding elastic pyramidal microstructures on one side of the electrode and using a thin layer of a dielectric in a capacitive sensor. The sensitivity of the proposed device has been improved from 3.1 to 70.6 kPa−1 compared to capacitive sensors having pyramidal microstructures in the same dimension on the dielectric layer. Moreover, a detection limit of 1 Pa was achieved. The finite element analysis performed based on electromechanical sequential coupling simulation for hyperelastic materials indicates that the microstructures on electrode are critical to achieve high sensitivity. The influence of the duty ratio of the micro-pyramids on the sensitivity of the sensor is analyzed by both simulation and experiment. The durability and robustness of the device was also demonstrated by pressure testing for 2000 cycles.

scholarly journals Investigation of sensitive element for pressure sensor based on bipolar piezotransistor

2021 ◽  
Author(s):  
Mikhail ◽  
Denis Prigodskiy
Keyword(s):  
Pressure Sensor ◽  
Output Signal ◽  
Dynamic Range ◽  
Strong Dependence ◽  
Pressure Sensors ◽  
High Sensitivity ◽  
Wheatstone Bridge ◽  
Differential Amplifier ◽  
Sensor Output ◽  
Thin Part

The article translated from Russian to English on pp. 691-693 (please, look down). The paper summarizes results of investigation of high-sensitivity MEMS pressure sensor based on a circuit containing both active and passive stress-sensitive elements: a differential amplifier utilizing two n-p-n piezotransistors and for p-type piezoresistors. A comparative analysis of a sensor utilizing this circuit with a pressure sensor based on traditional piezoresistive Wheatstone bridge and built on the same mechanical part is provided. MEMS pressure sensor with the differential amplifier (PSDA) has sensitivity of S = 0.66 mV/kPa/V, which exceeded the sensitivity of the element with piezoresistive Wheatstone bridge (PSWB) by 2.2 times. The sensitivity increase allows for the following sensor improvements: die size reduction, increase of diaphragm mechanical strength while keeping high pressure sensitivity, and simplifying requirements to external processing of the pressure sensor output signal. There are two main challenges related to the use of PSDA-based pressure sensors: strong dependence of output signal on temperature and higher than in PSWB noise reducing the dynamic range of the device to 10 3. The article describes methods of addressing these problems. The temperature dependence of sensor output signal can be minimized with help of an offset thermal compensation circuit and by eliminating metallization at the thin part of the diaphragm. The noise can be minimized by reducing the thickness of the active base region of the transistor. Circuit analysis with software NI Multisim shows that sensitivity of PSDA-based pressure sensor can be increased 2.3 times by circuit optimization.

SIMULATION METHODS OF PIEZORESISTIVE PRESSURE SENSORS IN ORDER TO IMPROVE CONSISTENCY

2012 ◽  
Vol 27 (02) ◽  
pp. 1350011 ◽  
Author(s):  
ZHAOHUA ZHANG ◽  
TIANLING REN ◽  
RUIRUI HAN ◽  
LI YUAN ◽  
BO PANG
Keyword(s):  
Pressure Sensor ◽  
Pressure Sensors ◽  
Simulation Method ◽  
Test Results ◽  
Silicon Membrane ◽  
Element Analysis ◽  
Piezoresistive Pressure Sensor ◽  
Consistency Results ◽  
Good Consistency ◽  
Piezoresistive Pressure Sensors

It is important to realize good consistency among different device units on a big wafer. The bad product consistency results from the processing deviation which is hard to control. A novel simulation method to control and reduce the influence of processing deviation on the sensitivity of a piezoresistive pressure sensor is provided in this paper. Based on finite element analysis (FEA) and mathematical integration, the performance of the pressure sensors is simulated. The pressure sensors are designed and fabricated according to the simulation results. The test results confirm that this simulation method can help to design the pressure sensor very precisely. From the simulation and test results, we find that properly enlarging the size of the square silicon membrane can improve the devices consistency.

Improving Linearity of Circular Capacitive Pressure Sensor by Using a Dimple Mask

2020 ◽  
Author(s):  
Md Ebrahim Khalil Bhuiyan ◽  
Mohammad Shavezipur
Keyword(s):  
Ambient Pressure ◽  
Pressure Sensors ◽  
Capacitive Pressure Sensor ◽  
Element Analysis ◽  
Flexible Membrane ◽  
Pressure Sensitive ◽  
The Finite Element Analysis ◽  
Wide Pressure Range ◽  
Capacitance Pressure ◽  
Wide Pressure

Abstract A new design concept for MEMS capacitive pressure sensors is presented that can be used to improve the linearity of the capacitance-pressure (C-T) response of the sensor. The sensor uses an extra dimple mask and etching step in the fabrication process of the device to create small bumps under the pressure sensitive and flexible membrane. Different designs, including a conventional sensor, are modeled and simulated using FEM coupled-field multiphysics solver in ANSYS®. Polycrystalline silicon is used as the structural material in the simulations. Coefficient of linear correlation between device capacitance and ambient pressure is used as the linearity factor to quantitatively compare the performance of different sensors. The finite element analysis show that the linearity factor improves from 0.938 for a conventional design to 0.973 for a design with a central bump. For a design with five bumps (one at the center of membrane and four off-center) the linearity factor increases to 0.997 for bumps of 1.5 μm thickness for wide pressure range of 0.0–4.0 MPa. The proposed design can be tailored for different applications that require certain sensor materials or different pressure ranges by using optimized sensor dimensions.

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