Non-contact Device Research Articles

Light Drone-Based Application to Assess Soil Tillage Quality Parameters.

The evaluation of soil tillage quality parameters, such as cloddiness and surface roughness produced by tillage tools, is based on traditional methods ranging, respectively, from manual or mechanical sieving of ground samples to handheld rulers, non-contact devices or Precision Agriculture technics, such as laser profile meters. The aim of the study was to compare traditional methods of soil roughness and cloddiness assessment (laser profile meter and manual sieving), with light drone RGB 3D imaging techniques for the evaluation of different tillage methods (ploughed, harrowed and grassed). Light drone application was able to replicate the results obtained by the traditional methods, introducing advantages in terms of time, repeatability and analysed surface while reducing the human error during the data collection on the one hand and allowing a labour-intensive field monitoring solution for digital farming on the other. Indeed, the profilometer positioning introduces errors and may lead to false reading due to limited data collection. Future work could be done in order to streamline the data processing operation and so to produce a practical application ready to use and stimulate the adoption of new evaluation indices of soil cloddiness, such as Entropy and the Angular Second Moment (ASM), which seem more suitable than the classic ones to achieved data referred to more extended surfaces.

A robust and efficient calibration method for spot laser probe on CMM

Among all the non-contact measurement devices, the spot laser probe achieves a good balance between accuracy and efficiency. When the laser probe is applied to three-dimensional (3-D) measurement, the laser beam direction is essential to transform the probe indication from 1-D distance information into a 3-D vector representing differences in space coordinates. In this article, a calibration method is proposed for the laser probe mounted on the coordinate measuring machine (CMM). During the calibration procedure, the CMM moves along the user-planned path and hundreds of points are scanned in a few seconds. In order to get an accurate laser beam direction estimate, we refine the original inaccurate direction, which is specified by the mechanical structure of the probe fixture, by mapping the scanned points into a sphere. The simulation and experiment manifest that the proposed method is superior to the existing methods and meets the requirement of the micron-level measurement.

About Non-Contact ECG Recording Devices

Modern electrocardiography research admits that periodic ECG recording (once a half year) is not effective for early diagnosing coronary artery disease, a heart attack, and sudden cardiac death..

Безконтактно измервателно устройство за определяне масата на птичи яйца

In this article a possibility of application of the non-contact method for prediction the poultry eggs weight in storage period of 21 days was researched. A prediction assessment was made by shape features, capacitance, resistance and conductance of eggs. Feature vectors were selected and reduced data by principal component and partial least squares regression methods were used. A non-contact device was proposed and developed to determine the egg weight by video sensor and measurement cell. In order to obtain data for post-processing, a software application was designed. The developed algorithms and procedures were applied to determine the eggs weight, whereby that parameter of eggs could be predicted with the lowest relative error. The survey results show that the eggs weight could be predicted by the proposed system for contactless measurement with accuracy of 94-98%.

Effects of pupillary dilation on ocular optical biometry outcomes in pediatric patients.

Pharmacological pupillary dilation is performed in comprehensive ophthalmological examinations and before biometric measurements. So far, there is no consensus regarding its impact on biometric measurements. This study's aim was to investigate the effects of pharmacological pupillary dilation on ocular biometric measurements in healthy children. This was a prospective, observational, non-randomized study of children (4-18 years of age) who were admitted for routine ophthalmological examination. Biometric measurements were performed, using a non-contact optical biometry device, both before and after pharmacological pupillary dilation with cyclopentolate hydrochloride. Intraocular lens power calculations were performed using Hill-RBF, Barrett, Olsen, Sanders-Retzlaff-Kraff/Theoretical, Holladay, and Hoffer Q formulas. Descriptive statistical analyses were also performed. The Wilcoxon signed-rank test was used to compare measurements before and after pharmacological pupillary dilation. Relationships between variables were analyzed using the Spearman-Brown rank correlation coefficient. The study included 116 eyes of 58 children (mean age, 8.4 ± 0.32 years; 34 girls). Significant changes were observed after pupillary dilation, compared with before pupillary dilation, in terms of anterior chamber depth, aqueous depth, and central corneal and lens thicknesses. No significant change was observed in axial length. Intraocular lens power calculations revealed no significant changes after pupillary dilation in most formulas except for the Olsen formula. The intraocular lens power was significantly inversely correlated with axial length and anterior chamber depth. Pharmacological pupillary dilation in children appeared to have no impact on axial length and intraocular lens power, but caused a significant increase in anterior chamber depth. The difference in anterior chamber depth measurements before and after pupillary dilation could be related to the optical biometry device model used. These outcomes should be considered in intraocular lens power calculations performed using anterior chamber depth parameters.

Analysis of non-contact electromagnetic impact device connected to boosting circuit

We propose a non-contact electromagnetic impact-torque device (EMI device) using induced currents, and its characteristics have been verified using 3-D finite element method (FEM) analysis and carrying out measurements on a prototype. This paper describes a new EMI device with a regenerative circuit. A boosting chopper circuit is connected to the proposed EMI device, and the impact torque is controlled using the regenerated power.

Method for the diagnosis of high-voltage dielectric elements during operation based on dynamic registration of electromagnetic radiation

Complex remote monitoring and the developed non-contact diagnostic device (NDD) allow monitoring the technical condition and revealing the residual life of high-voltage dielectric elements. It is based on non-contact remote periodic measurement of a set of diagnostic parameters (characteristics of electrical discharges emitted by insulators during operation) necessary for a reliable assessment of the operating state of high-voltage dielectric equipment at the moment of operation and determination of its residual life. NDDs are installed on each phase conductor and used to measure diagnostic parameters, followed by computer processing of the accumulated information signals. An analysis of the set of necessary diagnostic parameters makes it possible to form a conclusion on the degree of performance of dielectric elements. The paper considers a method for detecting defective high-voltage insulators using the developed non-contact diagnostic devices by the radio frequency method and assessing the difference in time of arrival of a partial discharge signal.

Experimental Study on the Cable Tension Based on Non-Contact Dynamic Deflection Equipment

For the contact and wired measurement technology of cable tension, the factors of complicated bridge site conditions, data acquisition and transmission, wave data processing and sensor contact should be considered in practical application, which affect seriously the measure result accuracy, work efficiency and the measure feasibility. In order to improve the limitation of the existing cable tension measurement technology, the feasibility and key factors of non-contact dynamic deflection measurement technology is studied. A cable specimen with length of 12m was designed and made, and the steel strand is used in it, and the non-contact vibration testing device is used. The frequency and tension of the cable and the strain of steel strands are analyzed, and the results show that the effect of measure target position on the fundamental frequency of the cable is obviously little, and the tension of the subsequent steel strand can decrease the tension strain of the stretched steel strand, that is, the tension of the stretched steel strand is reduced. Furthermore, the maximum difference between calculated and measured tension of the cable is about 17.7% during loading stage. When the unloaded cable tension is less than 20.6%, the difference between calculated and measured tension is less than 10.0%. It can be seen that the tension and tension loss of the cable can be accurately estimated by using the non-contact dynamic deflection technology, and it can improve the work efficiency and the measure feasibility due to the less measure targets and larger data transmission distance.

A non-contact pneumoelectric device for liquid viscosity measurement

A non-contact pneumoelectric device for liquid viscosity measurement

Monitoring Wound Healing With Contactless Measurements and Augmented Reality.

Objective: This work presents a device for non-invasive wound parameters assessment, designed to overcome the drawbacks of traditional methods, which are mostly rough, inaccurate, and painful for the patient. The device estimates the morphological parameters of the wound and provides augmented reality (AR) visual feedback on the wound healing status by projecting the wound border acquired during the last examination, thus improving doctor-patient communication. Methods: An accurate 3D model of the wound is created by stereophotogrammetry and refined through self-organizing maps. The 3D model is used to estimate physical parameters for wound healing assessment and integrates AR functionalities based on a miniaturized projector. The physical parameter estimation functionalities are evaluated in terms of precision, accuracy, inter-operator variability, and repeatability, whereas AR wound border projection is evaluated in terms of accuracy on the same phantom. Results: The accuracy and precision of the device are respectively 2% and 1.2% for linear parameters, and 1.7% and 1.3% for area and volume. The AR projection shows an error distance <1 mm. No statistical difference was found between the measurements of different operators. Conclusion: The device has proven to be an objective and non-operator-dependent tool for assessing the morphological parameters of the wound. Comparison with non-contact devices shows improved accuracy, offering reliable and rigorous measurements. Clinical Impact: Chronic wounds represent a significant health problem with high recurrence rates due to the ageing of the population and diseases such as diabetes and obesity. The device presented in this work provides an easy-to-use non-invasive tool to obtain useful information for treatment.

Design and Experimental Study of Non-contact Power Transmission Device in Static Push-type Rotary Steering Drilling System

For improvement of contactless power transformer which is used in rotary steering system, this paper uses simulation method to study on the influence of the shape of the ferrite, the number os turns and installation position on the efficiency and power of the contactless power transformer. As well as, the author take several test to study the influence of environment, fixed position, etc. on this equipment and the regularity of power and efficiency. The research shows that the contactless power transformer is competent for rotary steering system, and the axial installation error impact the transmission efficiency and power which has the most power and efficiency at -3mm axial fixed position and ±3mm fixed position error can meet the rotary steering system requirements.

Prediction Of OSA severity using sound data collected by a non-contact device

Prediction Of OSA severity using sound data collected by a non-contact device

Noncontact Phased-Array Ultrasound Facilitates Acute Wound Healing in Mice.

The authors developed a noncontact low-frequency ultrasound device that delivers high-intensity mechanical force based on phased-array technology. It may aid wound healing because it is likely to be associated with lower risks of infection and heat-induced pain compared with conventional ultrasound methods. The authors hypothesized that the microdeformation it induces accelerates wound epithelialization. Its effects on key wound-healing processes (angiogenesis, collagen accumulation, and angiogenesis-related gene transcription) were also examined. Immediately after wounding, bilateral acute wounds in C57BL/6J mice were noncontact low-frequency ultrasound- and sham-stimulated for 1 hour/day for 3 consecutive days (10 Hz/90.6 Pa). Wound closure (epithelialization) was recorded every 2 days as the percentage change in wound area relative to baseline. Wound tissue was procured on days 2, 5, 7, and 14 (five to six per time point) and subjected to histopathology with hematoxylin and eosin and Masson trichrome staining, CD31 immunohistochemistry, and quantitative polymerase-chain reaction analysis. Compared to sham-treated wounds, ultrasound/phased-array-treated wounds exhibited significantly accelerated epithelialization (65 ± 27 percent versus 30 ± 33 percent closure), angiogenesis (4.6 ± 1.7 percent versus 2.2 ± 1.0 percent CD31 area), and collagen deposition (44 ± 14 percent versus 28 ± 13 percent collagen density) on days 5, 2, and 5, respectively (all p < 0.05). The expression of Notch ligand delta-like 1 protein (Dll1) and Notch1, which participate in angiogenesis, was transiently enhanced by treatment on days 2 and 5, respectively. The authors' noncontact low-frequency ultrasound phased-array device improved the wound-healing rate. It was associated with increased early neovascularization that was followed by high levels of collagen-matrix production and epithelialization. The device may expand the mechanotherapeutic proangiogenesis field, thereby helping stimulate a revolution in infected wound care.

Numerical characterisation of the performance of flow rate on a non-contact vortex gripper

On manufacturing industries like semiconductor wafers, Manufacturing of medicine or Food processing industries require repeated handling of clean products such as wafers, Food products, etc. which are needs to be frequently handled and transported. This handling can be further ameliorated by Vortex Grippers. Vortex levitation can achieve Non-Contact handling by blowing air through a tangential nozzle into a vortex cup, thus swirling air flow forms which generates negative pressure. The suction force generated by the vortex is more than enough to keep the workpiece without contact. In the present study, a non-contact handling device called vortex gripper is modified by changing some design parameters. However, when a conical shaped vortex cup is used, a 60% increase in gripper lifting force is achieved with the same air consumption as reported early.

Utility of MolecuLight i:X for Managing Bacterial Burden in Pediatric Burns.

Pediatric burn injuries are vulnerable to severe complications, most often infection, making prompt and precise diagnosis of bacterial bioburden vital to preventing detrimental consequences and optimizing patients' outcomes. Currently, burn wounds are assessed for infection via examining the clinical signs and symptoms of infection, which can be confirmed by swab culture analysis. While the former approach is subjective and experience-dependant, the latter technique is susceptible to missing subsurface, biofilm-associated colonization, and any peripheral bacterial burden, and also delays confirmation by up to 5 days. The MolecuLight i:X is a handheld, noncontact fluorescence imaging device, which can reveal real-time information about clinically significant levels of bacteria and their biodistribution in surface and subsurface burn wound tissues. We conducted a single-center observational study to assess the device efficacy in identifying critical bacterial levels in pediatric burn wounds and to test the children's compliance and the overall feasibility of the device integration into the current diagnostic practice. Ten patients with 16 wounds were recruited and assessed for the presence or absence of clinical signs and symptoms of infection and the presence or absence of bacterial fluorescence on images, with swabs taken to confirm findings. Results demonstrate the device's ability to visualize clinically significant bacterial burden and to localize distribution of pathogens. All clinicians agreed on the high compliance with the device and high feasibility of incorporating the device into routine wound assessments. The results of this study may pave the way toward including bacterial fluorescence imaging into the standard diagnostic algorithm for pediatric burn population.

Effects of Advanced Glycation Endproducts on the Mechanical Properties of Posterior Tibialis in Individuals with Diabetes Mellitus

Category:DiabetesIntroduction/Purpose:Advanced glycation endproducts (AGEs) accumulate in tendon tissue in individuals with diabetes mellitus (DM). Although AGEs have been shown to impact tendon function by decreasing collagen sliding, this relationship has not been explored in humans with diabetes. Despite the prevalence of foot deformity in this population and implications of posterior tibialis dysfunction, the mechanical behavior of the posterior tibialis tendon has only been reported in a small (n=5), cadaveric study that did not report DM status. Therefore, the purpose of this study is to determine the effects of DM-associated AGEs accumulation on the mechanical properties of the posterior tibialis tendon.Methods:Posterior tibialis tendons were collected from individuals with and without DM undergoing lower extremity amputation. A 1-2 mm tendon transection was used for AGEs quantification. AGEs were quantified via fluorescence following papain digestion and hydrolyzation as described previously. Fluorescence was compared to a quinine standard to calculate AGEs content, which was normalized to sample wet weight. Tensile mechanical testing was completed with the remaining specimen (˜25 mm long). Tendon cross-sectional area was measured with a non-contact laser scanning device. Specimens were preloaded to 10 N and preconditioned for 10 cycles at 6% strain, subjected to stress-relaxation at 6% strain for 10 minutes, and loaded with a triangular waveform to a maximum of 10% strain at a rate of 1% strain per second. Individual values and group descriptive statistics are reported for AGEs content and mechanical testing. Relationships between AGEs content and various mechanical testing parameters were evaluated using Spearman correlation.Results:Six individuals (5 with DM, 4 male, mean(SD) age: 56(5)years) were included. AGEs content was increased in DM tendon (DM: 20.5(5.1), non-DM: 9.5 ng quinine/mg wet weight). Compared to non-DM tendon, DM tendons had larger cross-sectional area (DM: 44.3(4.9), non-DM: 11mm2). From stress relaxation, DM tendons had smaller peak (DM: 0.41(0.25), non-DM: 1.16 MPa) and equilibrium stress (DM: 0.23(0.13), non-DM: 0.83 MPa), and larger percent relaxation (DM: 46(6)%, non-DM: 29%)(Figure 1-A). DM tendons had decreased maximum stress at 10% strain (DM: 0.63(0.45), non-DM: 1.75 MPa), increased linear stiffness (DM: 35.2(27.6), non-DM: 19.2N/mm), and decreased linear modulus (DM: 8.5(7.0), non-DM: 20.1 MPa)(Figure 1-B, C) compared to non- DM tendon. Hysteresis (i.e., energy loss upon unloading) was higher in DM tendons (DM: 0.35(0.05), non-DM: 0.22), and positively correlated to AGEs (rho=0.943, p=0.005, Figure 1-D).Conclusion:Posterior tibialis tendons with DM exhibited increased AGEs content and altered mechanical properties. DM tendons were less stiff when accounting for cross-sectional area but had 2-4x the cross-sectional area of non-DM tendon, with inconsistent patterns in total tendon stiffness potentially attributable to several factors. DM tendons showed impaired energy storage and return, which was most strongly associated with AGEs. Non-DM samples were limited and the linear modulus was smaller than previously reported, however, all but one DM tendon had a modulus less than 50% of the non-DM sample. Future work will explore the mechanisms of AGEs-associated DM tendon impairments.

Analysis of relation between skin elasticity and the entropy of skin image using near-infrared and visible light sources.

Skin elasticity has been regarded as one of the main indicators of skin condition. Current measurement devices for skin elasticity are mostly expensive for home-use and should contact the skin surface. As a first step to develop improved methods, we focus on the relation between skin elasticity and the entropy of skin images. Reduced skin elasticity causes wrinkles. It spreads frequency components and increases their randomness in the frequency domain. The randomness is quantified as entropy, which is a measure of the disorder of a system in physics. Therefore, skin elasticity is expected to have a negative relation with entropy. This tendency can be improved by applying penetration depth characteristics according to the wavelength of light. From cheeks and forehead of 12 Korean adults, skin images are acquired with three different light sources (470 nm, 870 nm and broadband light) and skin elasticity is measured. The root mean square error between the measured data and the fitted model is "0.27" (870 nm), "0.49" (broadband light) and "1.42" (470 nm). Furthermore, the results are analyzed by classifying by sex, age and measurement area. This study demonstrates the possibility of developing noncontact home-use devices to measure skin elasticity in the future.

Smartphone-based fundus photography for screening of plus-disease retinopathy of prematurity.

Inadequate screening of treatment-warranted retinopathy of prematurity (ROP) can lead to devastating visual outcomes. Especially in resource-poor communities, the use of an affordable, portable, and easy to use smartphone-based non-contact fundus photography device may prove useful for screening for high-risk ROP. This study evaluates the feasibility of screening for high-risk ROP using a novel smartphone-based fundus photography device, RetinaScope. Retinal images were obtained using RetinaScope on a cohort of prematurely born infants during routine examinations for ROP. Images were reviewed by two masked graders who determined the image quality, the presence or absence of plus disease, and whether there was retinopathy that met predefined criteria for referral. The agreement between image-based assessments was compared to the gold standard indirect ophthalmoscopic assessment. Fifty-four eyes of 27 infants were included. A wide-field fundus photograph was obtained using RetinaScope. Image quality was acceptable or excellent in 98% and 95% of cases. There was substantial agreement between the gold standard and photographic assessment of presence or absence of plus disease (Cohen's κ = 0.85). Intergrader agreement on the presence of any retinopathy in photographs was also high (κ = 0.92). RetinaScope can capture digital retinal photographs of prematurely born infants with good image quality for grading of plus disease.

Relationship Between the Parameters of Corneal and Fundus Pulse Signals Acquired With a Combined Ultrasound and Laser Interferometry Technique.

PurposeTo estimate the relationship between the characteristics of the corneal pulse (CP) signal and those of the fundus pulse (FP) signal measured with a combined noncontact ultrasonic and laser interferometry technique in healthy subjects.MethodsTwenty-two healthy subjects participated in experiments that included measurements of intraocular pressure, ocular pulse amplitude, ocular biometry, blood pressure, and heart rate. Additionally, simultaneous recordings of CP and FP signals were acquired with a noncontact ultrasonic device combined with laser interferometry. Subsequently, ocular perfusion pressure (OPP) and the time and spectral parameters of CP and FP signals were computed. A system model was proposed to relate the FP signal to the CP signal.ResultsThe system model revealed that the eye globe transfers information between signals of the posterior and anterior eye, relatively amplifying higher spectral harmonics. The amplitude of the second CP harmonic is predicted by FPRMS and OPP (R2 = 0.468, P = 0.002). Partial correlation analysis showed that the CP signal parameters are statistically significantly correlated with those of the FP signal and OPP, after correcting for age and sex.ConclusionsThe eye globe can be viewed as a high pass filter, in which the CP characteristic changes in relation to the fundus pulsation. The FP signal and OPP have an impact on the variations of the CP signal morphology.Translational RelevanceInvestigation of differences between the characteristics of the anterior and posterior tissue movements is a promising method for evaluating the role of circulatory and biomechanical components in the pathophysiology of ocular diseases.

Grasping of Soft Tissues By Means Of Non-Contact Gripper In Minimally Invasive Surgery

Surgeons need grippers to grasp and handling organs when performing Laparoscopic interventions. These grippers usually have toothed profile to prevent the slippage of the organs and therefore, tissue damage may occur during the operation. There should be a solution to this risk of damage. The tissue can manipulate without pinching or even touching it. Non-contact grippers that work with Bernoulli principle are used in the industrial field. The aim of the study investigates the feasibility of Bernoulli principle for manipulation soft tissues along minimally invasive surgery. In this study, a contactless gripper working with the principle of Bernoulli has been developed. Lifting force increases as a result of increasing the air flow velocity, gripper surface and nozzle radius. In order to prevent tissue damage, air deflector is used on gripper to change the direction of the air flow. The robot gripper was designed with venturi channels to increase the radial flow velocity. The effect of venturi channels on the lifting force were tested. This study demonstrate that a non-contact gripping device is applicable to lift flexible materials such as soft tissues in Minimally invasive surgery.