Ultrasonic Generator Research Articles

Machine learning-based shear force quality prediction of ultrasonic wire bonds: utilizing process data and machine data without additional sensors

Ultrasonic wire bonding is a highly automated production process that is used billions of times a year in the electronics and electromobility industries. Due to the complexity of the process and the large number of influencing parameters, there are currently no automated methods that can be used without additional sensors to evaluate the shear force bond quality quantitatively and non-destructively with sufficiently high precision. For this reason, this paper presents a new methodology that uses machine learning to enable quantitative, non-destructive prediction of bond quality without additional sensors. For this purpose, a machine learning algorithm was developed that uses various machine data and process data from existing sensors to quantitatively predict the shear force of the bonded joint. In addition, features are extracted from process time series, such as current, power, and frequency of the ultrasonic generator as well as deformation during bonding. Of the total of 2,090 features considered, the number of features could be reduced to 26 by recursive feature elimination, while maintaining the prediction accuracy. By using optimized deep neural networks, on average, a prediction precision of the regression on the shear force of the source bond of over 89.6% R2-score and a mean absolute error of 241 cN can be achieved.

Numerical Simulation of Rock Vibration Response under Ultrasonic High-Frequency Vibration with High Confining Pressure

As deep oil and gas resources and Carbon Capture and Storage (CCS) are developed, enhancing drilling efficiency in hard rock formations has emerged as a critical technology in oil and gas extraction. The advancement of ultrasonic, high-frequency vibration rock-breaking technology significantly facilitates efficient rock crushing. When subjected to ultrasonic high-frequency vibrations, the rock’s response is a crucial issue in implementing ultrasonic vibration rock crushing technology. This study employed numerical simulation and theoretical deduction methods, utilizing a multi-physics approach that couples solid mechanics with pressure acoustics. It integrated information on common influencing parameters of ultrasonic generators and reservoir rock properties to establish model parameters, analyze simulation results, and perform theoretical deductions. The research investigated the response patterns of different-sized rock samples under high-frequency ultrasound vibration excitation across various frequencies, amplitudes, and confining pressure conditions. Through the development of a three-dimensional model and the application of principles from solid mechanics and elastoplasticity, the study derived equations that describe the resonance frequencies of rock blocks under confining pressure as functions of relevant rock parameters. The findings indicate that ultrasonic vibrations can effectively induce rock displacement. Under excitation frequency sources, the rock exhibits a natural frequency correlated with the rock sample size. When the excitation frequency approximates the natural frequency, the rock resonates. At this point, the rock’s surface displacement is maximal. The rock undergoes tensile stress, leading to stress concentration that facilitates rock damage and fragmentation. Increasing the excitation amplitude enhances rock crushing, as it amplifies the maximum surface displacement under the same frequency excitation. Confining pressure exerts an inhibitory effect on the rock’s vibration response, but it does not alter the resonance frequency of the rock sample, a fact verified by both numerical simulation and theoretical results. Based on the research findings in this paper, it can help to optimize the parameters of ultrasonic vibration rock breaking in field application to achieve the best rock-breaking effect.

AI-enabled IoT-based pest prevention and controlling system using sound analytics in large agricultural field

Modern agriculture is more scientific, analytical, and technological. IoT technology has smartened agriculture. This upheaval changed farming and created many opportunities. However, farmers contend with extreme concerns that lead to production losses. Pests are the most significant contributors to the economic losses that occur in agriculture. Because of this, farmers extensively use pesticides to combat pests that affect plant life. To address this issue, a study proposes the implementation of an AI-enabled system that uses real-time data from the IoT and advanced analytics technologies to detect, prevent, and control pests. The primary objective is to reduce the dependence on pesticides and minimize their harmful impact on our surroundings. The recommended method uses a PID infrared sensor to detect the pests using body heat. Sound analytics records pest sounds to confirm their existence in the field. Once sound analytics and a PID sensor confirm the existence of pests, an ultrasonic generator produces ultrasonic waves that repel pests from the agricultural field. The feature matrices and statistics measures were obtained from 1750 pest sounds using LPCC algorithm. The data was then trained, validated, and tested using DenseNet system models. The proposed system generated ultrasonic sound at multiple frequencies. These frequencies affect pests' hearing, making them uncomfortable in their surroundings. The proposed DenseNet model achieved pest detection accuracy of 99.65%, a sensitivity of 99.53%, a specificity of 98.06%, a recall of 98.89%, a precision of 99.29%, and an F1 score of 98.87%, which is superior to the ANN, SVM, RCNN, YOLO, and KNN techniques that are currently in use. The average design efficiency for preventing and controlling pests has achieved 98.87%.

Online and Ex Situ Damage Characterization Techniques for Fiber-Reinforced Composites under Ultrasonic Cyclic Three-Point Bending.

With ultrasonic fatigue testing (UFT), it is possible to investigate the damage initiation and accumulation from the weakest link of the composite material in the very high cycle fatigue (VHCF) regime in a shorter time frame than conventional fatigue testing. However, the thermal influence on the mechanical fatigue of composites and the scatter in fatigue data for composites under ultrasonic cyclic three-point bending loading still need to be investigated. In this study, we conducted interrupted constant-amplitude fatigue experiments on a carbon-fiber satin-fabric reinforced in poly-ether-ketone-ketone (CF-PEKK) composite material. These experiments were carried out using a UFT system, which operates at a cyclic frequency of 20 kHz with a pulse-pause sequence. Various parameters, such as the CF-PEKK specimen's surface temperature, acoustic activity, and the ultrasonic generator's input resonance parameters, were measured during cyclic loading. During experiment interruption, stiffness measurement and volumetric damage characterization in the CF-PEKK specimens using 3D X-ray microscopy (XRM) were performed. The locations of damage initiation and accumulation and their influence on the changes in in situ parameters were characterized. Under fixed loading conditions, damage accumulation occurred at different locations, leading to scattering in fatigue life data. Further, the damage population decreased from the surface to the bulk of the composite material.

Анализ возможностей оптимизации выбора ультразвукового оборудования для нанесения функциональных покрытий

To meet the requirements affecting the quality of functional coatings, various technologies are currently being used, one of which is the use of ultrasonics. To form functional coatings, ultrasonics are used both at the stage of surface preparation and at the stage of coating deposition. Thus, at the stage of surface preparation, ultrasonics allow making surface preclean, ensuring the necessary surface roughness due to ultrasonic rolling, as well as preactivation of the surface before nitriding due to surface plastic deformation. In case of coating deposition, ultrasonics contribute to better nitriding and painting. However, ultrasonic equipment used in various preparation and coating deposition processes differs significantly in its characteristics. Thus, the ultrasonic generators vary in alternator capacity, specific material consumption, actual frequency, as well as design features that ensure stable operation, for example, automatic frequency control. The converters differ from each other in accomplishable amplitudes, power and actual frequency. In this regard, the aim of the work is to develop recommendations on the use of ultrasonic equipment in various technical processes for the creation of functional coatings. The paper studies ultrasonic equipment used in surface preparation and functional coating application process. The main process-dependent parameters aimed at choosing the required equipment have been characterized. Recommendations are given on the use of ultrasonic equipment for various functional coatings generation, when a converter-generator couple is found and it meets the requirements for most surface preparation and coating deposition processes.

Design and development of a variable ultrasonic frequency generator for rodents repellent

Rodent is one of the major stored pests in Bangladesh, which causes a huge problem in the food sector. They substantially harm to crops and other valuable items on a large scale. Chemically rodent repellents already exist, but because of their toxicity and high price, they are not recommended for use in food storage. The aim of the study was to develop an electronic rodent-repelling circuit that is capable of generating variable ultrasonic frequencies. These frequencies cause discomfort for pests including rats, and nocturnal insects, which affects their aural senses. A device was successfully designed and constructed by microcontroller, printed circuit board, passive infrared sensor, liquid crystal display, Relay module, and other relative components. The device was vigorously tested in Precision Lab, Bangladesh Agricultural University. Laboratory tests were conducted to evaluate the device's repellent efficacy, considering factors such as range, coverage area, power consumption, and durability. The device functioned as it detected the presence of rodents and then released frequency by the positive signal for 30 s. The device generated ultrasonic signals within the range of 20–125 kHz and detected signals from any live substances up to 4.5 m with an error of a maximum of ±0.428 %. The frequency range of rodent hearing is approximately 20 Hz to 300 kHz, with the greatest sensitivity between 30 and 70 kHz, affecting their aural senses and causing discomfort. Therefore, the developed ultrasonic rodent-repellent circuit can be a practical and sustainable solution for repelling stored rodents, which mitigates storage losses caused by rodent infestations.

Повышение эффективности очистки канализационных труб

Today, the level of accessibility to water supply and sewage systems, their technical condition, and the quality of maintenance and cleaning are among the elements determining the quality of life in cities and small settlements. Efficient sewage systems are vital to maintaining environmental safety, the established sanitary norms, and the conditions of people’s comfortable accommodation. All these factors require the communal services of cities and megalopolises to maintain sewage systems in proper technical conditions, minimize operational costs, extend the service life of the systems, and organize and implement new treatment technologies. According to experts, the main enemy of the internal sewage systems is grease abundant in domestic wastewater. The initially warm wastewaters are soon cooled in the pipe, and grease impurities settle on the walls of the sewage pipe. The layer of grease deposits may trap other impurities, thus contributing to the formation of a larger and more complex clog. The development and implementation of new contemporary methods of treatment of sewage systems and, particularly, the use of ultrasonic vibrations reduces operational costs, extends the service life of the systems, and ensures environmental safety. For these purposes, the ultrasonic generator UZG-10 of 10 kW capacity was used, as well as the magnetostrictive ultrasonic transducer with a magnetoconductor with three rods. The middle rod is equipped with finished windings that rigidly connect the free ends of the other rods. The provided scheme of transducer manufacturing increases the efficiency of pipe treatment and significantly reduces energy costs.

Ultrasonic tool shank with multiple vibration mode for micro-nano drilling: Design, optimization and experiment

The machining effects of hole drilling is limited by merely changing the amplitude. Adjusting ultrasonic vibration frequency to expand the matching range of machining parameters optimization is necessary to improve hole drilling effects. Therefore, the design, optimization, and experiment evaluation for a novel integrated, fined, low-cost dual-frequency ultrasonic tool shank is proposed, which can work in three vibration modes for micro-nano precision drilling. The principle of the dual-frequency ultrasonic transducer is introduced. The electro-mechanical equivalent circuit model with step horn is applied to study the dual-frequency characteristics. The transducer displacement equation model based on the wave equation theory is deduced to find the shared vibration node of the first and third frequency. Sensitivity analysis by equivalent circuit model and Finite element method (FEM) simulation of the key parameter is both conducted to optimize ultrasonic transducer geometry dimension. The vibration node of mounting flange is specified in an identical position for the dual vibration modes. A prototype of ultrasonic tool shank is fabricated and evaluated in experiments. It demonstrates that the dual working frequency of the ultrasonic transducer is 34.9 kHz and 104.5 kHz in the first and third mode resonant vibration, which is benefit to the low and high frequency drilling. Three working modes of the low, high, and coupling frequency vibration is measured by a self-developed ultrasonic generator. When 40 V voltage is excited, the vibration amplitudes of the low and high frequency are 17.8 µm, and 9.3 µm, respectively, which can meet with the drilling requirement. Moreover, the coupling vibration with the low and high mode are excited simultaneously, and the motion trajectory of the coupling vibration is observed in a “M” shape, which is a novel trajectory for the precision micro-nano drilling. Micro drilling experiments show that the 35 kHz ultrasonic vibration drilling can achieve better machining effect than conventional drilling (CD). The 105 kHz ultrasonic drilling outperforms the CD, 35 kHz and coupling ultrasonic drilling at cutting force reduction. The coupling ultrasonic vibration drilling achieves the lowest chipping diameter. It is to be noted that the 105 kHz-8 µm produce the fined smoothly surface. The 35 kHz, 105 kHz and coupling ultrasonic drilling can produce better surface micro morphology with less quantity and size of craters than that of CD.

Ультразвуковое формообразование изделий из мелкодисперсных порошков

The article deals with the current state of the physics and technology of the process of ultrasonic molding (USM) of products from finely dispersed metal and non-metal powders. The relevance of a comprehensive consideration of the process is substantiated, structural and technological schemes for its implementation are presented, types of ultrasound sources – ultrasonic transducers and ultrasonic generators, as well as designs and methods for calculating concentrators (transformers) of ultrasonic vibrations are given. The results of experimental studies of the USM process as applied to fine powders of various physical and chemical nature are analyzed. Physical models of the USM process are presented and discussed.

Possibilities of organizing microclimate systems on the basis of ultrasonic mist generator

Possibilities of organizing microclimate systems on the basis of ultrasonic mist generator

DEVELOPMENT AND RESEARCH OF THE FUNCTIONAL POSSIBILITIES OF THE AUTOMATED FUZZY INDOOR AIR QUALITY MANAGEMENT SYSTEM OF PRODUCTION PREMISES

Purpose. Development of a fuzzy indoor air quality control system and research of the efficiency of an automated complex for increasing the concentration of air ions, namely a small-sized ultrasonic generator of air ions and a pump unit in the conditions of a complex ventilated air environment of work premises. Design/methodology/approach. The comprehensive research carried out is important in the context of the development of measures and means and the research of their effectiveness in maintaining the aeroionic regime of industrial premises at the regulatory level. Conclusions. The structure of an intelligent indoor air quality control system is proposed, which implements a combined change in the rotation speed of the fan and pump and the power of the ultrasonic aeroion generator. For the first time, a formalized criterion for the optimality of the indoor air quality management system is proposed, which depends on individual preferences of people regarding the comfort of the production environment and standardized parameters of temperature, relative humidity, and concentration of air ions in the working space. The task of the intelligent control system is to minimize the proposed criterion. Limitations/consequences of research. The proposed recommendations are universal and can be used in various areas of business to create safe and harmless working conditions in production. Practical consequences. The use of the developed small-sized ultrasonic aeroion generator not only significantly increases the concentration of aeroions in the working area, but also due to the baloelectric effect minimizes the negative impact inherent in most existing ionizers, namely the generation of ozone and nitrogen oxide, which significantly improves indoor air quality and thereby increases the level of industrial safety and labor protection. Originality/meaning. The existing control systems assume that standard ionizers (corona discharges) are inserted in the room, so there was a need to develop and research a modern intelligent system for controlling the quality of the indoor air in the working area of industrial premises using an aeroion generator and automated displacement ventilation.

Investigation of surface topography in ultrasonic-assisted turning of C45 carbon steel

This study compares ultrasonic-assisted turning to conventional turning in terms of their effects on surface texture and cutting forces during the machining of C45 carbon steel. Experiments were conducted on a lathe equipped with a 1000 W ultrasonic generator running at 20 kHz. Ultrasonic-assisted turning results in small, evenly distributed spherical scratches on the workpiece, while conventional turning leads to long, uneven cutting marks. Significantly, ultrasonic-assisted turning achieves a notably smoother surface finish than conventional turning. As the depth of cut increases, conventional turning causes increasingly uneven surface topography, whereas ultrasonic-assisted turning maintains surface stability and uniformity. Moreover, cutting forces see a substantial rise of approximately 40% with conventional turning as the depth of cut increases. In contrast, ultrasonic-assisted turning witnesses a marginal force increase of about 15.84%.

Damage assessment during ultrasonic fatigue testing of a CF-PEKK composite using self-heating phenomenon

The knowledge and experience with the very high cycle fatigue (VHCF) behavior are limited compared to the low cycle and high cycle fatigue behavior of fiber-reinforced composite materials. Accelerated cyclic loading using an ultrasonic fatigue testing system is one potential solution to evaluate the longevity of composite materials within a reasonable time. Insufficient sampling rates and the inherent inaccuracies of non-contact measurement devices pose critical challenges in the adaptation of accelerated fatigue experiments. This study aims to overcome these challenges by combining the temperature response of the composite specimen and the input parameters for the dynamic response of the in-house developed ultrasonic fatigue testing system to detect damage before failure. Increasing- and constant-amplitude fatigue experiments were conducted on a carbon fiber satin fabric-reinforced poly-ether-ketone-ketone (CF-PEKK) composite material. These experiments were carried out under three-point bending loading conditions at a cyclic frequency of about 20 kHz. Various parameters, such as the surface temperature, the cyclic displacement, and the input resonance parameters of the ultrasonic generator, were recorded during these experiments. The VHCF behavior of the CF-PEKK material system was characterized based on these results and through digital light optical microscopy.

Design, modeling and experiment of a novel ultrasonic elliptical vibration generator

Design, modeling and experiment of a novel ultrasonic elliptical vibration generator

Experimental and application of waste rubber low‐temperature green regeneration through ultrasound‐assisted method

AbstractCombining a traditional mixer and a custom‐built ultrasonic generator, low‐temperature green regeneration of waste rubber was realized. Through orthogonal experiments, the optimal process parameters for the low‐temperature green regeneration through the ultrasound‐assisted (LTGRTUA) method were explored. Results showed that the self‐developed reclaimed rubber exhibited the best performance under the following conditions: rotor speed of 70 rpm, regeneration temperature of 85°C, ultrasonic power of 700 W, and ultrasonic loading time of 240 s. Additionally, the bond‐breaking types of the reclaimed rubber were evaluated through the measurements of sol fraction and desulfurization rate, as well as by using the Horikx curve. The self‐developed reclaimed rubber showed better retention of the main chain structure of waste rubber compared to the commercially reclaimed rubber which was prepared by the traditional vulcanization tank high‐temperature regeneration (TVTHTR) method. Moreover, blending experiments were conducted, in which different proportions of the reclaimed rubber replaced natural rubber (NR) for the purpose of producing tread rubber for radial tires. Performance tests of the final products revealed that the self‐developed reclaimed rubber performed better than commercially reclaimed rubber, which provides an effective basis for the subsequent industrial application and promotion.Highlights Low‐temperature green regeneration of waste rubber was realized by the LTGRTUA method. The main chain structure of waste rubber is well preserved by the LTGRTUA method. The self‐developed reclaimed rubber has better properties and industrial application prospects.

Prototype of ultrasonic sensor-based generator fuel monitoring as a generator fuel level measuring device in the Organizing Unit Dr. F.L Tobing Airport

Dr. Ferdinand Lumbantobing Sibolga Airport Management Unit has three generators with different capacities. The first engine has a capacity of 50 KvA, the second engine is 125 KvA, and the third engine, which is a standby engine and connected to an Acos panel, has a capacity of 250 KvA. This 250 KvA generator serves as a backup if the power supply from PLN goes out, to provide electricity for the Terminal, Office, AFL, Power house, and Dr. F.L. Tobing Airport Tower. This airport gets a current supply of 345 KvA from PLN. Generators are widely known for acting as a backup power source when PLN is off, used at various scales, including at airports. Genset is important to maintain the availability of electricity in aviation safety services. However, generator fuel monitoring at UPBU Dr. F.L. Tobing needs to be improved, because currently it only uses an indicator hose without a fuel exhaustion alarm. This can result in the shutdown of the generator set when fuel is low, so it is necessary to check the fuel capacity periodically while operating to avoid interruptions in power supply. The research method used is quantitative method.

Investigation to Dual-Frequency Direct Digital Synthesis and Resonance Frequency Tracking in Power Ultrasonic Generator

Investigation to Dual-Frequency Direct Digital Synthesis and Resonance Frequency Tracking in Power Ultrasonic Generator

Importance of nanorobots in pharma and medical field

Machines built at the molecular level (referred to as "nanomachines") may be utilized to treat the human body of its numerous diseases. Nanorobotics is the science of building machines or robots at or near the scale of a nanometre (10-9 meters). Nanomedicine is the term used to describe this application of nanotechnology to the field of medicine. Future-looking uses for nanotechnology include minuscule robots that can build other machines, navigate inside the body to distribute drugs, or do microsurgery. Chemists are discovering how to use protein dynamics to power micro and nano size machines using catalytic processes, drawing inspiration from the biological motors of live cells. The toolkit for nanorobots includes items like a cavity for storing medication, probes, blades, and chisels to remove plaque and obstructions, microwave emitters, and ultrasonic signal generators to destroy cancerous cells, two electrodes generating an electric current, heating the cell up until it dies, powerful lasers could burn away harmful material like arterial plaque. A cream incorporating nanorobots that remove the proper amount of dead skin, remove excess oils, add missing oils, apply the right amounts of natural moisturizing ingredients, and even accomplish the elusive objective of "deep pore cleaning" may be utilized to treat skin problems. Other uses include the treatment of gout, kidney stones, gouty arthritis, parasite elimination, cancer treatment, and arteriosclerosis treatment.

Research on the machining mechanism of AISI 304 ultrasonic vibration assisted grinding

Compared with conventional grinding (CG), ultrasonic vibration assisted grinding (UVAG) has more prospects and competitiveness in processing AISI 304. Due to the change of strength of materials, when the vibration is superimposed on the workpiece, the mechanism of ultrasonic assisted machining is different from that of tool ultrasonic assisted machining. Therefore, this article proposes a workpiece vibration grinding device suitable for UVAG to study the corresponding grinding mechanism. The vibration characteristics of workpiece ultrasonic generator were discussed based on finite element simulation and the vibration situation of the device was tested with instruments to verify the accuracy of the simulation. Meanwhile, the machining mechanism of workpiece ultrasonic vibration was studied through grinding comparative experiments. The experiment showed that the displacement curve of the output end of the ultrasonic vibration of AISI 304 with time could be approximated to a sine wave and there was no other clutter. As the amplitude percentage of the ultrasonic generator increased, the output amplitude of the transducer showed an increasing trend. The ultrasonic amplitude and the amplitude percentage of ultrasonic generator approximately follow a linear relationship. The grinding force decreased with the increase of spindle speed and amplitude, and increased with the increase of feed rate and grinding depth. Compared with conventional grinding force, the grinding force of tangential ultrasonic vibration assisted grinding (TUVAG) decreased by about 29 %, while the grinding force of radial ultrasonic vibration assisted grinding (RUVAG) decreased by about 28 %. Under the action of ultrasound, the workpiece obtained better surface morphology. Under processing conditions of vw = 25 mm/min, ap = 0.01 mm, n = 2000r/min, A = 8 μm, f = 20000 Hz, the minimum surface roughness Ra of TUVAG is 0.51, followed by RUVAG with Ra = 1.02, while the surface roughness Ra of CG is the worst at 1.56 due to grinding burns.

Design ultrasonic power generators for welding machines using piezoelectric ceramic materials for welding on non-woven fabrics

This paper presents the design and manufacture of ultrasonic emitters for welding machines using piezoelectric ceramic materials for welding on non-woven fabrics. The ultrasonic vibrating membrane (UVB) used for the transducer is investigated to ensure that there are no cracks in the material structure. These parameters serve as the basis for evaluating the quality of the ultrasonic vibrating membrane in the fabrication of an oscillator for ultrasonic transducer welding (USTW). The ultrasonic power generator (USPG) is made of high-frequency components and power components to supply electrical oscillations to the UVB. This vibrating source must be compatible with the USTW to operate at maximum efficiency. Due to the influence of the manufacturing process and USTW usage environment, after operating for a long time, the resonant frequency (fr) will be changed. Therefore, the USPG needs to monitor the frequency of the USTW automatically. Matching the impedance of USTW and USPG is very important to get the most out of USPG power. The fabrication results show that the use of high-resolution timer to generate the control frequency for USPG achieves high accuracy, with the largest error of 0.006% at 18401.12 Hz when surveyed in the range of 18 to 22 kHz. The parameters of control signal delay between two phases and pulse width also give very good results. Impedance-matching (IM) networks also show good exploitation of USPG when compared to USPG without IM.