Visualization of wheel-rail contact area of running vehicle using film sensor

2021 ◽  
pp. 095440972110418
Author(s):  
Shinya Fukagai ◽  
Takashi Toyama ◽  
Takayuki Tanaka ◽  
Masahito Kuzuta ◽  
Hisayo Doi
Keyword(s):  
Contact Area ◽  
Pressure Sensor ◽  
Measurement Method ◽  
Dynamic Contact ◽  
Contact Condition ◽  
Dynamic Interactions ◽  
Film Sensor ◽  
Cross Sectional ◽  
Vehicle Operation ◽  
Contact Position

Proper evaluation of the wheel-rail contact is necessary to understand the dynamics of railway vehicles and the causes of wear and damage to components such as wheels and rails. Numerical methods are often used to evaluate the dynamic contact condition between the wheel and rail; however, there are few promising methods for experimental evaluation. It is important to develop a measurement method because the wheel-rail contact is easily changed owing to vehicle-track dynamic interactions. In this study, we used a film-based pressure sensor equipped with force-sensitive resistors to measure the contact area between the wheel and rail during vehicle operation. Using the film-based pressure sensor, we evaluated the geometry of the contact area and position. The validity of the measured contact position is evaluated by comparing it with the contact position based on the cross-sectional profiles of the wheel and rail and the wheelset displacement during a vehicle running.

An Observation Method of Real Contact Area during PVA Brush Scrubbing

2018 ◽  
Vol 282 ◽  
pp. 73-76 ◽  
Author(s):  
Toshiyuki Sanada ◽  
Masanao Hanai ◽  
Akira Fukunaga ◽  
Hirokuni Hiyama
Keyword(s):  
Contact Area ◽  
Contact Condition ◽  
Real Contact Area ◽  
Led Light ◽  
The Real ◽  
Real Contact ◽  
Observation Method

In the post CMP cleaning, the contact condition between PVA brush and surface is very important. In this study, we observed the real contact area between a brush and surface using a collimating LED light and prism. As a result, we found that the real contact area increases with increasing the brush compression. In addition, we also found that the real contact area decreases when the brush starts to move, and the brush was locally compressed due to its deformation.

scholarly journals Experimental Investigation of Fully Plastic Contact of a Sphere Against a Hard Flat

2005 ◽  
Vol 128 (2) ◽  
pp. 230-235 ◽  
Author(s):  
J. Jamari ◽  
D. J. Schipper
Keyword(s):  
Experimental Investigation ◽  
Contact Pressure ◽  
Contact Area ◽  
Measurement Method ◽  
Contact Load ◽  
Model Predictions ◽  
The Mean

In this paper we report the experimental investigation to evaluate the published models for the contact of a deformable sphere against a hard flat in the fully plastic contact regime. A new measurement method has been used to measure the contact area. The behavior of the mean contact pressure and the contact area as a function of the contact load are presented. Substantial differences are found between the measurements and the model predictions. A constant value of the mean contact pressure as the load increases is observed, however, the value is lower than the hardness, as often reported. The contact area is found to be a simple truncation of the sphere by a hard flat.

scholarly journals Non-destructive residual pressure self-measurement method for the sensing chip of optical Fabry-Perot pressure sensor

2017 ◽  
Vol 25 (25) ◽  
pp. 31937 ◽  
Author(s):  
Xue Wang ◽  
Shuang Wang ◽  
Junfeng Jiang ◽  
Kun Liu ◽  
Xuezhi Zhang ◽  
...  
Keyword(s):  
Pressure Sensor ◽  
Measurement Method ◽  
Residual Pressure ◽  
Fabry Perot ◽  
Non Destructive

Dynamic contact stress and frictional heat analysis of femoral head-on-acetabular cup interface based on calculation and simulation methods

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Xingxing Fang ◽  
Dahan Li ◽  
Yucheng Xin ◽  
Songquan Wang ◽  
Yongbo Guo ◽  
...  
Keyword(s):  
Finite Element ◽  
Femoral Head ◽  
Contact Stress ◽  
Contact Area ◽  
Gait Cycle ◽  
Dynamic Change ◽  
Dynamic Contact ◽  
Frictional Heat ◽  
Acetabular Cup ◽  
Content Type

Purpose The purpose of this paper is to systematically study the dynamic contact stress, frictional heat and temperature field of femoral head-on-acetabular cup contact pairs in a gait cycle. Design/methodology/approach In this paper, four common femoral head-on-acetabular cup contact pairs are used as the research objects, mathematical calculations and finite element simulations are adopted. The contact model of hip joint head and acetabular cup was established by finite element simulation to analyze the stress and temperature distribution of the contact interface. Findings The results show that the contact stress of the head-on-cup interface is inversely proportional to the contact area; high contact stress directly leads to greater frictional heat. However, hip joints with metal-on-polyethylene or ceramic-on-polyethylene paired interfaces have lower frictional heat and show a significant temperature rise in one gait cycle, which may be related to the material properties of the acetabular cup. Originality/value Previous studies about calculating the interface frictional heat always ignore the dynamic change process in the contact load and the contact area. This study considered the dynamic changes of the contact stress and area of the femoral head-on-acetabular cup interface, and four common contact pairs were systematically analyzed.

scholarly journals An evaluation of ultrasonic arrays for the static and dynamic measurement of wheel–rail contact pressure and area

2020 ◽  
Vol 234 (10) ◽  
pp. 1580-1593
Author(s):  
Henry Brunskill ◽  
Andy Hunter ◽  
Lu Zhou ◽  
Rob Dwyer Joyce ◽  
Roger Lewis
Keyword(s):  
Contact Pressure ◽  
Ultrasonic Transducer ◽  
Dynamic Contact ◽  
Pressure Profile ◽  
Calibration Procedure ◽  
Railway Vehicle ◽  
Profile Measurement ◽  
Two Dimensional ◽  
Cross Sectional ◽  
Contact Conditions

The interfacial contact conditions between a railway vehicle wheel and the rail are paramount to the lifespan, safety and smooth operation of any rail network. The wheel–rail interface contact pressure and area conditions have been estimated, calculated and simulated by industry and academia for many years, but a method of accurately measuring dynamic contact conditions has yet to be realised. Methods using pressure-sensitive films and controlled air flow have been employed, but both are limited. Ultrasonic reflectometry is the term given to active ultrasonics in which an ultrasonic transducer is mounted on the outer surface of a component and a sound wave is generated. This ultrasonic wave packet propagates through the host medium and reflects off the contacting interface of interest. The reflected waveform is then detected and contact area and interfacial stiffness information can be extracted from the signal using the quasi-static spring model. Stiffness can be related to contact pressure by performing a simple calibration procedure. Previous contact pressure measurement work has relied on using a focusing transducer and a two-dimensional scanning arrangement which results in a high-resolution image of the wheel–rail contact, but is limited to static loading of a specimen cut from a wheel and rail. The work described in this paper has assessed the feasibility of measuring a dynamic wheel–rail contact patch using an array of 64 ultrasonic elements mounted in the rail. Each element is individually pulsed in sequence to build up a linear cross-sectional pressure profile measurement of the interface. These cross-sectional, line measurements are then processed and collated resulting in a two-dimensional contact pressure profile. Measurements have been taken at different speeds and loads.

scholarly journals A Measurement Method of Microsphere with Dual Scanning Probes

2019 ◽  
Vol 9 (8) ◽  
pp. 1598 ◽  
Author(s):  
Fang ◽  
Huang ◽  
Xu ◽  
Cheng ◽  
Chen ◽  
...  
Keyword(s):  
Measurement Method ◽  
Coordinate Measuring Machine ◽  
Quartz Tuning Fork ◽  
Cross Sectional ◽  
Scanning Probes ◽  
Repeatability Error ◽  
Measurement Results ◽  
Size Standard ◽  
Measuring Machine ◽  
Tungsten Tip

The probe tip of a micro-coordinate Measuring Machine (micro-CMM) is a microsphere with a diameter of hundreds of microns, and its sphericity is generally controlled within tens to hundreds of nanometers. However, the accurate measurement of the microsphere morphology is difficult because of the small size and high precision requirement. In this study, a measurement method with two scanning probes is proposed to obtain dimensions including the diameter and sphericity of microsphere. A series of maximum cross-sectional profiles of the microsphere in different angular directions are scanned simultaneously and differently by the scanning probes. By integrating the data of these maximum profiles, the dimensions of the microsphere can be calculated. The scanning probe is fabricated by combining a quartz tuning fork and a tungsten tip, which have a fine vertical resolution at a sub-nano scale. A commercial ruby microsphere is measured with the proposed method. Experiments that involve the scanning of six section profiles are carried out to estimate the dimensions of the ruby microsphere. The repeatability error of one section profile is 15.1 nm, which indicates that the measurement system has favorable repeatability. The mainly errors in the measurement are eliminated. The measured diameter and roundness are all consistent with the size standard of the commercial microsphere. The measurement uncertainty is evaluated, and the measurement results show that the method can be used to measure the dimensions of microspheres effectively.

scholarly journals In Situ Rubber-Wheel Contact on Road Surface Using Ultraviolet-Induced Fluorescence Method

2020 ◽  
Vol 10 (24) ◽  
pp. 8804
Author(s):  
Jhonni Rahman ◽  
Yutaka Shoukaku ◽  
Tomoaki Iwai
Keyword(s):  
Contact Area ◽  
High Speed ◽  
High Sensitivity ◽  
Dynamic Contact ◽  
Road Surface ◽  
Oxide Semiconductor ◽  
Small Scale ◽  
In Situ Observation ◽  
On The Road

This study examines the relationship between rubber-wheel and the contact area on the road surface. Ultraviolet-induced fluorescence microscopy was used to observe and measure the contact parts with pyranine as a dye solution. The high sensitivity to U.V. light makes it easy to distinguish contact and non-contact regions on a very small scale. The experiment was conducted in static and dynamic conditions to identify its influence on the apparent contact area of rubber-wheel and road surface. The in-situ observation of the contact area was captured and recorded using a high-speed digital camera with 1-inch a CMOS (complementary metal oxide semiconductor) sensor. Additionally, the contact area between rubber-wheel and road surface was measured using an analyzing software. The results show differences in static and dynamic contact conditions based on the operating parameters.

scholarly journals The Role of Wettability on the Response of a Quartz Crystal Microbalance Loaded with a Sessile Droplet

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Brandon Murray ◽  
Shankar Narayanan
Keyword(s):  
Contact Angle ◽  
Frequency Response ◽  
Quartz Crystal Microbalance ◽  
Contact Area ◽  
Quartz Crystal ◽  
Quartz Substrate ◽  
Dynamic Contact Angle ◽  
Dynamic Contact ◽  
Decay Length ◽  
Sessile Droplet

AbstractIn this work, the interaction between a sessile droplet’s contact angle and a quartz crystal microbalance (QCM) is elucidated. We differentiate the QCM’s frequency response to changes in the droplet contact area from variations in the dynamic contact angle. This is done by developing a computational model that couples the electrical and mechanical analysis of the quartz substrate with the visco-acoustic behavior of the sessile droplet. From our analysis, we conclude that changes in the contact angle have an effect on the frequency response of the QCM when the droplet height is on the order of the viscous decay length or smaller. On the other hand, changes in the interfacial contact area of the sessile droplets have a significant impact on the frequency response of the QCM regardless of the droplet size.

Sign in / Sign up

Export Citation Format

Share Document