In-Process Weighing Systems

2011 ◽  
Author(s):  
Rami Elbeltagi ◽  
Alona Ben-Tal ◽  
Johan Potgieter ◽  
Jen-Yuan James Chang
Keyword(s):  
High Speed ◽  
Power Spectra ◽  
Experimental System ◽  
Force Sensor ◽  
Load Cell ◽  
Diverse Range ◽  
Load Cells ◽  
Oscillatory Response ◽  
Food Load ◽  
A Chain

In-process electronic high speed weighing systems play an important role in the highly automated, continuously evolving industrial world of today. They are an essential component in sorting, grading and quality control within a diverse range of industries, including; robotics, automotive and food. Load cells are considered to be the definitive force sensor for industrial weighing systems. Load cell output is in the form of an oscillatory response in which the measurand contributes to the response parameters. Current methods require the oscillatory response to settle in order to achieve an accurate measurement. This is time consuming and speed limiting. The focus of this paper is to find alternative weighing analysis methods for a system which utilises two load cells, placed either side of a carrier travelling on a chain conveyor, running at speeds of 10 items a second. It is necessary to determine the value of the measurand in the fastest time possible to speed up the process and increase throughput. This has been approached by mathematically modelling the system to allow accurate prediction of the weights passing the load cells before the settling time of the oscillatory response. Simple models of harmonic motion have been considered for the motion of a load cell. An experimental system was built and weighing data collected for different speeds and loads. Power spectra of the weighing data was analysed to determine dominant frequencies and estimate system parameters. This paper describes the work done to date on load cell modelling and improving an in-process electronic weighing system by successfully predicting the weight during the transient period of the oscillatory response. The assumptions and results of both simulations and experimental data are presented.

scholarly journals Physical Simulations of High Speed and Low Power NanoMagnet Logic Circuits

2018 ◽  
Vol 8 (4) ◽  
pp. 37 ◽  
Author(s):  
Giovanna Turvani ◽  
Laura D’Alessandro ◽  
Marco Vacca
Keyword(s):  
High Speed ◽  
Logic Circuits ◽  
Micromagnetic Simulations ◽  
Electrical Fields ◽  
Nanomagnet Logic ◽  
Nanomagnetic Logic ◽  
Elastic Effect ◽  
Physical Simulations ◽  
A Chain ◽  
Beyond Cmos

Among all “beyond CMOS” solutions currently under investigation, nanomagnetic logic (NML) technology is considered to be one of the most promising. In this technology, nanoscale magnets are rectangularly shaped and are characterized by the intrinsic capability of enabling logic and memory functions in the same device. The design of logic architectures is accomplished by the use of a clocking mechanism that is needed to properly propagate information. Previous works demonstrated that the magneto-elastic effect can be exploited to implement the clocking mechanism by altering the magnetization of magnets. With this paper, we present a novel clocking mechanism enabling the independent control of each single nanodevice exploiting the magneto-elastic effect and enabling high-speed NML circuits. We prove the effectiveness of this approach by performing several micromagnetic simulations. We characterized a chain of nanomagnets in different conditions (e.g., different distance among cells, different electrical fields, and different magnet geometries). This solution improves NML, the reliability of circuits, the fabrication process, and the operating frequency of circuits while keeping the energy consumption at an extremely low level.

scholarly journals Optical Coherence Tomography as a Tool for Ocular Dynamics Estimation

2015 ◽  
Vol 2015 ◽  
pp. 1-8 ◽  
Author(s):  
Damian Siedlecki ◽  
Waldemar Kowalik ◽  
Henryk Kasprzak
Keyword(s):  
Heart Rate ◽  
Optical Coherence Tomography ◽  
Spectral Analysis ◽  
High Speed ◽  
Anterior Segment ◽  
Power Spectra ◽  
Optical Coherence ◽  
Tomographic Images ◽  
Noninvasive Estimation ◽  
Ocular Hemodynamics

Purpose. The aim of the study is to demonstrate that the ocular dynamics of the anterior chamber of the eye can be estimated quantitatively by means of optical coherence tomography (OCT).Methods. A commercial high speed, high resolution optical coherence tomographer was used. The sequences of tomographic images of the iridocorneal angle of three subjects were captured and each image from the sequence was processed in MATLAB environment in order to detect and identify the contours of the cornea and iris. The data on pulsatile displacements of the cornea and iris and the changes of the depth of the gap between them were retrieved from the sequences. Finally, the spectral analysis of the changes of these parameters was performed.Results. The results of the temporal and spectral analysis manifest the ocular microfluctuation that might be associated with breathing (manifested by 0.25 Hz peak in the power spectra), heart rate (1–1.5 Hz peak), and ocular hemodynamics (3.75–4.5 Hz peak).Conclusions. This paper shows that the optical coherence tomography can be used as a tool for noninvasive estimation of the ocular dynamics of the anterior segment of the eye, but its usability in diagnostics of the ocular hemodynamics needs further investigations.

scholarly journals Open Source Digitally Replicable Lab-Grade Scales

2020 ◽  
Author(s):  
Benjamin R. Hubbard ◽  
Joshua M. Pearce
Keyword(s):  
Open Source ◽  
Low Cost ◽  
Cost Savings ◽  
Load Cell ◽  
Significant Cost ◽  
Load Cells ◽  
The Cost ◽  
Cell Data ◽  
Precision Balance ◽  
Multiple Load

This study provides designs for a low-cost, easily replicable open source lab-grade digital scale that can be used as a precision balance. The design is such that it can be manufactured for use in most labs throughout the world with open source RepRap-class material extrusion-based 3-D printers for the mechanical components and readily available open source electronics including the Arduino Nano. Several versions of the design were fabricated and tested for precision and accuracy for a range of load cells. The results showed the open source scale was found to be repeatable within 0.1g with multiple load cells, with even better precision (0.01g) depending on load cell range and style. The scale tracks linearly with proprietary lab-grade scales, meeting the performance specified in the load cell data sheets, indicating that it is accurate across the range of the load cell installed. The smallest loadcell tested(100g) offers precision on the order of a commercial digital mass balance. The scale can be produced at significant cost savings compared to scales of comparable range and precision when serial capability is present. The cost savings increase significantly as the range of the scale increases and are particularly well-suited for resource-constrained medical and scientific facilities.

scholarly journals Design and Realization of a Miniature Capacitive Silicon Force Sensor for Loads up to 500 KG

2000 ◽  
Author(s):  
R. A. F. Zwijze ◽  
R. J. Wiegerink ◽  
G. J. M. Krijnen ◽  
T. Hien ◽  
M. C. Elwenspoek
Keyword(s):  
Force Sensor ◽  
Full Scale ◽  
Load Cell ◽  
Measurement Results ◽  
Previous Design ◽  
Cell Force

Abstract In this paper, a micromachined silicon load cell (force sensor) is presented for measuring loads up to 500 kg. The load cell has been realized and tested. Measurement results show a hysteresis error of ±0.02% of the full-scale output (fso). Creep at 500 kg after 30 minutes is within 0.01% of the fso. These measurements show that the performance has improved by a factor of 10 compared to the previous design.

A Load Cell System in Foot Pressure Analysis

1982 ◽  
Vol 11 (3) ◽  
pp. 121-122 ◽  
Author(s):  
W V James ◽  
J F Orr ◽  
T Huddleston
Keyword(s):  
Low Cost ◽  
Cell System ◽  
Load Cell ◽  
Foot Pressure ◽  
Cost System ◽  
Pressure Sensitive ◽  
Low Profile ◽  
Load Cells ◽  
Pressure Analysis

A method of displaying discrete areas of pressure beneath the foot has been produced. The device employs a pressure sensitive elastomer which gives quantitative readings of the pressure developed. The 512 load cells are enclosed in a low profile platform only one inch in depth which provides a low-cost system that can be employed in clinical situations.

A FE Modelling Method for the Thermal Characteristics of High-Speed Motorized Spindle

2016 ◽  
Vol 693 ◽  
pp. 3-10
Author(s):  
Jia Rui Wang ◽  
Ping Fa Feng ◽  
Zhi Jun Wu ◽  
Ding Wen Yu ◽  
Jian Fu Zhang
Keyword(s):  
High Speed ◽  
Thermal Contact ◽  
Convective Heat Transfer Coefficient ◽  
Thermal Characteristics ◽  
Experimental System ◽  
Research Field ◽  
Motorized Spindle ◽  
Fe Modelling ◽  
Simulation Accuracy ◽  
Modelling Method

Finite element simulation is an effective method to study the thermal characteristics of high-speed motorized spindle, how to improve the simulation accuracy has become the key point of this research field. This paper presents a FEA method using ANSYS to precisely predict the thermal characteristics of high-speed spindle. Firstly, the heating and cooling characteristics of high-speed spindle are analyzed, main heating source, convective heat transfer coefficient, and thermal contact resistance are calculated. Secondly, FEA model of the machine center is built, the temperature field and thermal deformation of the spindle system are simulated. Thirdly, an experimental system to test thermal characteristics is designed, simulation results are compared with the experimental results. The result shows that the simulation errors are controlled in a relative low range, the FE modelling method can precisely predict the thermal characteristics of the motorized spindle.

Mechanism of Cavitation Erosion at the Exit of a Long Orifice

2003 ◽  
Author(s):  
Yoshinori Yagi ◽  
Michio Murase ◽  
Keiichi Sato ◽  
Shuji Hattori
Keyword(s):  
High Speed ◽  
Cavitation Erosion ◽  
Propagation Speed ◽  
Video Camera ◽  
Concentric Circle ◽  
Collapse Mechanism ◽  
Pressurized Water ◽  
Flow Passage ◽  
Cavity Collapse ◽  
A Chain

We carried out experiments to clarify the mechanism of cavitation erosion at the exit of a long orifice equipped at a pressure-reducing line in a pressurized water reactor (PWR). In order to ascertain the mechanism of cavitation erosion at the first stage and progression stage, we used a high-speed video camera. As a result, we observed cavity collapse near the exit of the orifice under oscillating flow conditions, which might be a major factor in the first stage of erosion at the exit of the orifice. To simulate the progression stage, we used an orifice with a cone-shaped flow passage at its exit, corresponding to an orifice diffuser. We observed cavity collapse near the exit, after which cavities that existed upstream in the cone shape collapsed in a manner similar to a chain reaction. The propagation speed varied with the quantity of cavities in the cone-shaped flow passage and cavities collapsed in a concentric circle pattern. Thus, the cavity collapse mechanism was concluded as follows: a pressure wave (shock wave) was generated by cavity collapse near the exit, then propagated upwards, and consequently caused cavity collapse upstream. This mechanism might promote cavitation erosion in an upward direction.

Nonlinear Dynamics of Electrokinetic Instabilities

2005 ◽  
Author(s):  
Jonathan D. Posner ◽  
Juan G. Santiago
Keyword(s):  
Electric Fields ◽  
High Speed ◽  
Power Spectra ◽  
Epifluorescence Microscopy ◽  
Bulk Liquid ◽  
Sample Stacking ◽  
Electrokinetic Instability ◽  
Absolute Flow ◽  
Electrokinetic Flows ◽  
Continuous Power

Electrokinetic instabilities are generated by a coupling of electric fields and ionic conductivity gradients. This coupling results in an electric body force in the bulk liquid that can generate temporal, convective, and absolute flow instabilities. In this work, we perform a parametric experimental study of convective instabilities in cross-shaped microchannels using epifluorescence microscopy and high speed digital imaging. We report temporal power spectra and spatiotemporal maps as a function of the applied field. The spectral analyses reveal that disturbances induced by electrokinetic instability are purely sinuous at the onset of instability and exhibit higher-order harmonics, frequency bifurcations, and continuous power spectra with increasing electric Rayleigh number. Electrokinetic instabilities (EKI) in cross-shaped channels are relevant to injections for field amplified sample stacking, electrokinetic flows at the intersections in multi-dimensional assay devices, and systems with indeterminate sample chemistry.

Validation of an Atomistic Field Theory for Contact Electrification Using a MEMS Load Cell

2019 ◽  
Author(s):  
Tyler J. Hieber ◽  
Mohamad Ibrahim Cheikh ◽  
James M. Chen ◽  
Zayd C. Leseman
Keyword(s):  
Field Theory ◽  
High Speed ◽  
Sliding Mode ◽  
Close Contact ◽  
Michelson Interferometer ◽  
Load Cell ◽  
Cell Stiffness ◽  
Contact Potential ◽  
Aft Model ◽  
Contact Electrification

Abstract This work depicts an experimental method for the validation of an Atomistic Field Theory (AFT) model for contact electrification of dielectrics. The AFT model is used to simulate the effects of Triboelectric Nanogenerators (TENGs) for energy harvesting. Recently, the AFT model has shown that contact electrification can be described by the induced surface dipoles when two dissimilar materials are brought into close contact assuming that the crystal lattices are free of defects, no residual strain in the materials is present and that the experiment is performed in vacuum. These simulations have been used to predict the induced contact potential between MgO and BaTiO3. To validate the AFT model, a set of quasi-static experiments will be conducted to test two different operating modes of TENGs, which can be mirrored in the simulations. The first experiment is a micro-scale pull-in/pull-off test in which a pad of single crystal Si (SCSi) will be brought into and out of contact with a dielectric substrate (thermally grown SiO2). The second experiment will mimic the TENG during sliding operation. A SCSi microcantilever will be brought into contact with the dielectric surface and displaced in sliding mode. These experiments will be conducted using a custom, reusable MEMS load cell and an electrometer to monitor the interaction forces and induced charge on the surfaces. To obtain the required displacement resolution of the load cell, a high-speed Michelson interferometer will be used. This allows for higher load cell stiffness to accommodate for surface adhesion effects. The load cell will be calibrated using the well-known technique of hanging masses from the load cell. The relative distance between the interacting surfaces in both experiments will be controlled by a piezo stage with 1 nm resolution. Results from these experiments are to be compared to the AFT model results.

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