Feed Motion Research Articles

Effectiveness of Watching a Kumagai Method Video for Long-Nipple Bottle-Feeding for Children with Cleft Lip and Palate: A Pilot Experimental Before-After Trial Study.

This study aimed to determine whether the Kumagai method could be followed by watching an instructional video and to compare the feeding actions of specialists and the general population. Eleven adults from diverse backgrounds were recruited and asked to feed a baby doll using a bottle feeder with a long nipple, and their actions were recorded. Then, they watched a 2.5-min instructional video of the Kumagai method and were asked to bottle-feed again. Video recordings of the participants were used to evaluate whether their actions followed the Kumagai method. Differences in the feeding actions of the specialists and participants were determined from still images in the videos. The McNemar test was used to analyze the differences between the participants' actions before and after. The Kruskal-Wallis test was also used to determine differences between the actions of participants and specialists. Feeding movements significantly improved after watching the video. Participants' actions, which differed significantly from those of the specialists, were evident in "the angle of the nipple at the moment the nipple was brought close to the lips" and "the angle change of the nipple from the lip to the mouth". Watching our short instructional video was effective in improving the technique of the Kumagai method; however, it is insufficient for feeding a real child with cleft lip and palate. Including the rationale of each action in the video and adding direct instruction as a supplement is required.

The Kumagai Method: Feeding Techniques Using the Pigeon Baby Cleft Palate Bottle.

This study aimed to identify the P-bottle feeding techniques systematically organized by Ms. Kumagai, an expert in nursing care for children with a cleft lip and/or palate (CLP), which were developed as she gained expertise in feeding affected children. We recruited three nurses who had mastered the Kumagai method for feeding with a P-bottle. Through analysis of participants' voices and videos during interviews, we focused on aspects such as dealing with a closed mouth, inserting the nipple in cases of unilateral and bilateral CLP, dealing with the child's movements after insertion, and key considerations when squeezing the bottle. The interview analyses revealed numerous techniques used by nurses to manage the difficulties encountered while feeding children, ensuring successful provision of nourishment. Specifically, the nurses employed techniques such as placing the nipple along the midline of the child's tongue and varying the application of force on the nipple depending on the cleft type. The nurses reported that the objectives of these techniques were to prevent ulcer formation and encourage the use of the tongue, simulating original feeding movements. We explored feeding techniques and the management of associated challenges. Our results suggest that the "Kumagai Method" could be valuable in improving feeding practices.

Precaudal Vertebrae in the Postcranial Region of Moray Eels Form Ventral Processes.

Fish vertebrae are primarily morphologically classified into precaudal vertebrae jointed to the ribs and caudal vertebrae with hemal spines, through which the caudal artery and veins pass. Moray eels (family Muraenidae) capture prey by directly biting, combining oral and pharyngeal jaw. During feeding motions, they exhibit various head manipulations, such as neurocranial elevation, ventral flexion, and horizontal shaking, with their postcranial region acting like the neck of amniotes. However, the bone morphology supporting these movements remains unclear. In this study, the vertebral morphologies of the Kidako moray (Gymnothorax kidako), starry moray (Echidna nebulosa), pink-lipped moray (Echidna rhodochilus), tidepool snake moray (Uropterygius micropterus), and Seychelles moray (Anarchias seychellensis) were investigated using X-ray computed tomography. These five species exhibited longitudinal ventral processes in the second to approximately 12th precaudal vertebrae with canals for blood vessels, structurally similar to hemal spines. In addition, the morphology of the precaudal vertebrae in three Anguilliformes species closely related to moray eels and two Gasterosteiformes species, including a seahorse that flexes its head ventrally as a feeding motion, was compared with that of moray eels. However, no remarkable ventral processes were observed in their precaudal vertebrae in the postcranial region, suggesting that these structural features in the postcranial vertebrae were preserved in Muraenidae but not necessarily required for the fish to bend its head ventrally. Although the functional significance of the ventral process has yet to be determined, our findings highlight a novel aspect of fish vertebral morphology.

Parameter identification of Johnson–Cook constitutive model based on genetic algorithm and simulation analysis for 304 stainless steel

Addressing the significant discrepancy between actual experimental cutting force and its predicted values derived from traditional constitutive model parameter identification methods, a reverse identification research of the Johnson–Cook (J-C) constitutive model for 304 stainless steel was conducted via genetic algorithm. Considering actual cutting zone and the influence of feed motion on the rake (flank) angle, an unequal division shear zone model was established to implement the theoretical calculation for shear zone stress. Through cutting experiments, the spindle speed was negatively correlated with the cutting force at first, and then became positively correlated; The empirical formula (EXP model) for turning force was corrected, revealing that the EXP model was unable to provide optimal predicted values for cutting force. The influence of the J-C constitutive parameter C on the cutting morphology was firstly investigated through simulation analysis, and determined an appropriate value for C, then obtained the precise values for the other four constitutive parameters by genetic algorithm. Moreover, the simulated values of cutting force in JC1 model (obtained from the Split Hopkinson Pressure Bar test) and JCM model (the improved model using genetic algorithm) were obtained by three-dimensional (3-D) simulation via FEM software. The results indicated that, the maximum error between actual experimental cutting force and its simulated values (by JCM model) was 14.8%, with an average error of 6.38%. These results outperformed the JC1 and EXP models, suggesting that the JCM model identified via genetic algorithm was more reliable.

Analysis and Experiment of Thermal Field Distribution and Thermal Deformation of Nut Rotary Ball Screw Transmission Mechanism

This study designs a differential dual-drive micro-feed mechanism, superposing the two “macro feed motions” (“motor drive screw” and “motor drive nut”) using the same transmission of “the nut rotary ball screw pair” structure. These two motions are almost equal in terms of speed and turning direction, thus the “micro feed” can be obtained. (1) Background: Thermal deformation is the primary factor that can restrict the high-precision micro-feed mechanism and the distribution of heat sources differs from that of the conventional screw single-drive system owing to the structure and motion features of the transmission components. (2) Discussion: This study explores the thermal field distribution and thermal deformation of the differentially driven micro-feed mechanism when two driving motors are combined at different speeds. (3) Methods: Based on the theory of heat transfer, the differential dual-drive system can be used as the research object. The thermal equilibrium equations of the micro-feed transmission system are established using the thermal resistance network method, and a thermal field distribution model is obtained. (4) Results: Combined with the mechanism of thermal deformation theory, the established thermal field model is used to predict the axial thermal deformation of the differential dual-drive ball screw. (5) Conclusions: Under the dual-drive condition, the steady-state thermal error of the nut-rotating ball screw transmission mechanism increases with the increase in nut speed and composite speed and is greater than the steady-state thermal error under the single screw drive condition. After reaching the thermal steady state, the measured thermal elongation at the end of the screw in the experiment is approximately 10.5 μm and the simulation result is 11.98 μm. The experimental measurement result demonstrates the accuracy of the theoretical analysis model for thermal error at the end of the screw.

The "elongate chelicera problem": A virtual approach in an extinct pterygotid sea scorpion from a 3D kinematic point of view.

Chelicerae, distinctive feeding appendages in chelicerates, such as spiders, scorpions, or horseshoe crabs, can be classified based on their orientation relative to the body axis simplified as either orthognathous (parallel) or labidognathous (inclined), exhibiting considerable diversity across various taxa. Among extinct chelicerates, sea scorpions belonging to the Pterygotidae represent the only chelicerates possessing markedly elongated chelicerae relative to body length. Despite various hypotheses regarding the potential ecological functions and feeding movements of these structures, no comprehensive 3D kinematic investigation has been conducted yet to test these ideas. In this study, we generated a comprehensive 3D model of the pterygotid Acutiramus, making the elongated right chelicera movable by equipping it with virtual joint axes for conducting Range of Motion analyses. Due to the absence in the fossil record of a clear indication of the chelicerae orientation and their potential lateral or ventral movements (vertical or horizontal insertion of joint axis 1), we explored the Range of Motion analyses under four distinct kinematic settings with two orientation modes (euthygnathous, klinogathous) analogous to the terminology of the terrestrial relatives. The most plausible kinematic setting involved euthygnathous chelicerae being folded ventrally over a horizontal joint axis. This configuration positioned the chelicera closest to the oral opening. Concerning the maximum excursion angle, our analysis revealed that the chela could open up to 70°, while it could be retracted against the basal element to a maximum of 145°. The maximum excursion in the proximal joint varied between 55° and 120° based on the insertion and orientation. Our findings underscore the utility of applying 3D kinematics to fossilized arthropods for addressing inquiries on functional ecology such as prey capture and handling, enabling insights into their possible behavioral patterns. Pterygotidae likely captured and processed their prey using the chelicerae, subsequently transporting it to the oral opening with the assistance of other prosomal appendages.

Evaluation of Deviations for Horizontal Thin Walls Determined by Optical and Contact Methods for Milled Samples of Nickel Alloy Inconel 625

The aerospace industry is imposing increasingly strict dimensional tolerances, which is forcing continuous development in component manufacturing. Ensuring tight dimensional tolerances is difficult for thin-walled structures due to their reduced stiffness, which are increasingly used in the aerospace industry, where titanium alloys and nickel alloys, among others, dominate. Developments in this area are causing a search for machining conditions that provide sufficient quality characteristics including dimensional and shape accuracy. We discuss, herewith, thin wall deformations in the horizontal orientation of Inconel 625 nickel alloy samples in cross-sections perpendicular and parallel to the direction of tool feed motion. We measured dimensional and shape accuracy using a 3D optical scanner and also using a coordinate measuring machine to correlate these results. We compared the results obtained by the two methods and obtained the maximum discrepancy of the results equal to around 8%. Samples made with adaptive cylindrical milling had similar values of thin wall deviations, with the smallest deviations observed for the sample made with the tool for high-performance machining using adaptive cylindrical milling.

Surface Roughness Analysis and Optimization for ST 37 Steel in Lathe Operation using Design of Experiments Method

The machining process is one of the processes used to process steel materials. The value or level of material roughness is one of the values that is considered in the machining process, according to the desired roughness value. One example is in the turning process, spindle speed, depth of feed, and feed motion are factors that can affect the level of roughness of a material. The level of roughness that is not according to demand is one of the problems in the manufacturing industry, especially in the results of the turning process. One of the causes of the discrepancy in the roughness value is because the parameters used are not suitable. Therefore, this study aims to determine the optimal parameters in the turning process to obtain the optimal roughness value, and to determine the parameters that most influence the roughness of the turning process. In this study, ST 37 steel was used. This study used an experimental design method with Orthogonal Array L8. The experiment was carried out with 5 control factors and 3 noise factors. Each factor has 2 levels and is repeated 8 times. In this study using a conventional lathe and for roughness testing using a Surface Roughness Tester. Based on the results of data analysis, the movement factor has the highest influence on the surface roughness value. The ranking factors that affect the roughness value are as follows: spindle speed of 345 rpm, feed motion of 0.051 mm/rad, depth of cut 1 mm, dry cooling, and automatic sledding. The Design of Experiments (Taguchi) method use quality characteristics to determine the results of the analysis. In this study, the quality characteristic is smaller the better. Smaller the better characteristics is where the smaller value, then better the quality. In variations of the spindle rotation speed and feed motion, we get where if the spindle speed is high and the feed motion is low it will produce a low level of roughness, whereas if the spindle speed is low and the feed movement is high it will produce a high level of roughness.

Roughness of Face-Milled Surface Topography in Directions Relative to the Feed Movement

Roughness of Face-Milled Surface Topography in Directions Relative to the Feed Movement

On the effect of radial engagement on the milling stability of modes perpendicular to the feed direction

This paper analytically studies the effect of radial engagement on chatter stability when the flexibility is perpendicular to the feed motion, with thin-walled part milling being the most relevant industrial case. By studying the mean directional factor and its harmonics, the superior stability of the up-milling strategy over down-milling for both Hopf and flip chatter is demonstrated. The optimal engagement for a theoretical infinite stable depth of cut Hopf is obtained, as well as the expressions for the critical depth of cut. For flip chatter, three different cutting zones with different lobe shapes can occur depending on the radial engagement. It is also shown that while flip chatter cannot be completely eliminated by tuning the radial engagement alone, an engagement can be found in up-milling that maximises stability. Finally, the findings are validated through experimental tests.

Fabrication of micro tools using electrochemical machining with a reciprocating block electrode

Micro parts are increasingly being used in many applications. The machining of micro parts is inevitably dependent on micro tools, which play a key role in limiting the feature size and controlling the dimensional accuracy. However, the fabrication of micro tools is currently inefficient. This paper presents a novel electrochemical machining (ECM) method in which a reciprocating block (RBECM) is used as the tool electrode. In RBECM, the cylindrical workpiece reciprocates up and down in a straight line along its axis, while the block electrode simultaneously makes a feed movement. A mathematical model of the cutting edge length and width was derived to predict the size of the cutting edge tools. The results indicate that the model could achieve a good prediction accuracy. In addition, the effects of machining time on cutting edge width were experimentally investigated. Three types of stainless steel cutting edge tools with cutting edge widths of approximately 1/4, 1/2, and 3/4 of the diameter were successfully fabricated using a 5-mm-thick stainless steel block. The experimental results indicate that the machining time could be significantly reduced by 97.83–99.5% compared to the ECM method using a tensioned metal wire as the cathode.

Evaluation of the Surface Topography and Deformation of Vertical Thin-Wall Milled Samples from the Nickel Alloy Inconel 625.

During the production of components, manufacturers of structures are obliged to meet certain requirements and ensure appropriate quality characteristics. It is especially important during the manufacturing of thin-walled structures, which are subject to many errors during machining due to the reduced rigidity of the products, including the deformation of thin walls, which may be the result of the vibration of the system. The appearance of vibrations reduces the quality of the machined surface affecting the increase in the values of surface topography parameters-waviness and roughness. Thin-wall structures-titanium or nickel alloy, among others-play a key role in the aerospace industry, which constantly strives to reduce the weight of the entire structure while meeting requirements. The present work focuses on the evaluation of the parameters of surface topography, dimensional and shape accuracy during the milling of nickel alloy Inconel 625 samples containing a thin wall in a vertical orientation. The experiment was conducted under controlled cutting conditions using a constant material removal rate. As part of the surface topography section, the distribution of waviness, Wa and Wz, and roughness, Ra and Rz, was determined in selected measurement areas in the direction parallel to the direction of the feed motion. Dimensional deviations, measured with a 3D optical scanner, were determined in selected cross sections in the direction perpendicular and parallel to the bottom of the sample presenting the deflection of the thin-walled structure. The results provide information that the used parameter sets affect the measured quantities to varying degrees.

СИНТЕЗ СЛЕДЯЩЕЙ СИСТЕМЫ УПРАВЛЕНИЯ ЭЛЕКТРОПРИВОДАМИ ПОДАЧИ И ГЛАВНОГО ДВИЖЕНИЯ ТОКАРНОГО СТАНКА С ЧИСЛОВЫМ ПРОГРАММНЫМ УПРАВЛЕНИЕМ

Relevance Modern requirements for turning accuracy of parts during turning are constantly increasing. In order to provide them, in addition to using modern CNC machines and tooling, it is necessary to minimize errors arising during the operation of the machine drives (main and feed drives), as well as the cutting tool that is used during the process. This task can be carried out using specialized tracking systems for controlling the electric drive of a CNC lathe. The use of the control system allows you to control nondeterministic cutting parameters and ultimately provide the required amount of roughness. Aim of research The main aims of the research develop a model of the tracking system for controlling the feed and main motion of the CNC lathe. Research methods The control system model is synthesized using the MATLAB SIMULINK program. Results As part of the study, the MATLAB SIMULINK software package was used to develop a model of the tracking system for controlling the feed motors and the main motion of the CNC lathe. As a result of the operation of the servo control system, it has become possible to determine the values of non-deterministic cutting parameters, which will ensure the accuracy of processing the surfaces of the workpiece with a minimum error value.

ОПРЕДЕЛЕНИЕ ЭНЕРГОЕМКОСТИ ПРОЦЕССА ИЗМЕЛЬЧЕНИЯ РЕЗАНИЕМ В ИЗМЕЛЬЧИТЕЛЕ КОРМОВ

The relevance of the study is due to the need to reduce energy intensity and loss of nutritional value of feed while simultaneously improving quality indicators during the grinding process. The work was carried out with the aim of theoretical studies of the design and technological parameters of the feed chopper and determining the energy consumption of the grinding process by cutting. The scientific novelty of the research lies in the mathematical models for determining the cutting work and the total drive power of the feed chopper. When carrying out the research, the general scientific principles of the theory of elasticity, the theory of shells, and fracture mechanics were used, and the physical, mechanical and technological properties of feed of plant origin were also taken into account. A device is proposed, the design of which has the following advantages: a uniform supply of material to the cutting zone (to the knives) is ensured due to the working chamber in the form of a truncated cone, which leads to a consistent reduction in the size of the feed to those established by zootechnical requirements and improves its quality; the ability to change the angle of inclination of the rotary counter-cutting knives, which provides adjustment of the intensity of the grinding process; reduction in the energy intensity of grinding due to the free movement of crushed feed into the unloading chamber and the original shape of the tosser blade. Analytical expressions were obtained to determine the cutting work on each row of knives for one knife in a row, the total work of all knives per revolution, as well as the required power for the rotor drive. As a result of the research, it was established that the energy intensity of the grinding process is determined as the sum of the costs of cutting, acceleration of the material and idling of the rotor. The total power required to drive the chopper depends on the number, geometric characteristics of the chopper and counter-cutting knives, the rotor speed, and the properties of the material being crushed.

A Novel Tooth Modification Methodology for Improving the Load-Bearing Capacity of Non-Orthogonal Helical Face Gears

This study proposes a double-crown tooth surface modification technology that improves the load-carrying capacity of non-orthogonal helical tooth surface gears. The tooth modification is determined by a modified rack-cutter, and its feed motion is related to an intentionally designed transmission error. The novelty of the tooth modification design is that the transmission error can be pre-designed. First, changing the tooth profile of the tool enables preliminary modification along the tooth profile direction; second, by modifying the interaction between the tool and the machined gear, subsequent fine adjustments are made to the contact path. This two-stage tooth modification strategy not only retains the advantages of the traditional method but also significantly improves the balance of the load distribution on the tooth surface through an original contact path modification strategy. Through systematic tooth contact analysis (TCA) and loaded tooth contact analysis (LTCA), it was verified that the new method reduces contact stress and tooth root bending stress and improves the gear’s resistance to misalignment errors. This research provides the basis and motivation for further exploring and improving this tooth profile modification technology to solve the challenges faced by more complex gear systems.

Development of a Low Cost Extrusion Based 3D Printer for High Performance Engineering Polymers

The development of a low cost 3D printer is presented for high performance polymers by example of a PEI type material. The development steps and technical alternatives opted for during the design process are outlined in two cycles targeting first printing of non-demanding thermoplastics, such as ABS, PLA etc., followed by an upgrade to printing PEI and similar high performance polymers. Subsystems discussed pertain to the frame, CNC axes including feed motors and motion control, the extruder, hot end and nozzle. Of particular interest are modifications concerning the temperature setting and regulation subsystems of the printer work volume and the printing table. Calibration procedures with pitfalls and solutions is discussed and a documented series of finally successful tests for Ultem1010TM is presented.

A hybrid modeling method for predicting the cutting force in whirlwind milling of lead screw

Analyzing the cutting force in the process of lead screw whirlwind milling can help us understand the processing quality and processability. Whirlwind milling is a process in which multiple cutting tools are driven by the cutter head to sequentially cut and process the workpiece. The cutting force changes periodically in the process of lead screw whirlwind milling. Analyzing the cutting force of the nth cutting needs to consider the influence of the previous n-1 cutting. This paper employed a hybrid method combining mathematical modeling and finite element analysis to predict the cutting force in lead screw whirlwind milling. Firstly, the tool motion path of lead screw whirlwind milling is analyzed by considering the influence of cutter inclination angle and relative tool-workpiece motion. The relationship between the nth tool path and the (n-1)th tool path is analyzed by considering the feed motion of the tool and the rotation motion of the workpiece. Furtherly, mathematical models of the nth tool path and the (n-1)th tool path are established. Then, based on the established mathematical models, the three-dimensional geometric model of the tool and workpiece is established by three-dimensional software. The establishment of the workpiece geometry model considers the influence of the previous n-1 cutting. The tool geometry model rotates along the (n-1)th cutting path, and the tool intersects the workpiece. Finally, the finite element model of lead screw whirlwind milling is established based on the above three-dimensional geometric model. The periodical cutting force in the lead screw whirlwind milling is obtained by simulating the nth cutting with the finite element model. The relevant lead screw whirlwind milling experiment was carried out to verify the reliability of the model prediction. The appropriate processing parameter range of lead screw whirlwind milling is obtained through the process parameter optimization.

P1E5-04 Analysis of feeding movement in breast- and bottle-feeding

P1E5-04 Analysis of feeding movement in breast- and bottle-feeding

Energy Prediction Models and Distributed Analysis of the Grinding Process of Sustainable Manufacturing.

Grinding is a critical surface-finishing process in the manufacturing industry. One of the challenging problems is that the specific grinding energy is greater than in ordinary procedures, while energy efficiency is lower. However, an integrated energy model and analysis of energy distribution during grinding is still lacking. To bridge this gap, the grinding time history is first built to describe the cyclic movement during air-cuttings, feedings, and cuttings. Steady and transient power features during high-speed rotations along the spindle and repeated intermittent feeding movements along the x-, y-, and z-axes are also analysed. Energy prediction models, which include specific movement stages such as cutting-in, stable cutting, and cutting-out along the spindle, as well as infeed and turning along the three infeed axes, are then established. To investigate model parameters, 10 experimental groups were analysed using the Gauss-Newton gradient method. Four testing trials demonstrate that the accuracy of the suggested model is acceptable, with errors of 5%. Energy efficiency and energy distributions for various components and motion stages are also analysed. Low-power chip design, lightweight worktable utilization, and minimal lubricant quantities are advised. Furthermore, it is an excellent choice for optimizing grinding parameters in current equipment.

Preoperative Planning Framework for Robot-Assisted Dental Implant Surgery: Finite-Parameter Surrogate Model and Optimization of Instrument Placement.

For robot-assisted dental implant surgery, it is necessary to feed the instrument into a specified position to perform surgery. To improve safety and efficiency, a preoperative planning framework, including a finite-parameter surrogate model (FPSM) and an automatic instrument-placement method, is proposed in this paper. This framework is implemented via two-stage optimization. In the first stage, a group of closed curves in polar coordinates is used to represent the oral cavity. By optimizing a finite number of parameters for these curves, the oral structure is simplified to form the FPSM. In the second stage, the FPSM serves as a fast safety estimator with which the target position/orientation of the instrument for the feeding motion is automatically determined through particle swarm optimization (PSO). The optimized feeding target can be used to generate a virtual fixture (VF) to avoid undesired operations and to lower the risk of collision. This proposed framework has the advantages of being safe, fast, and accurate, overcoming the computational burden and insufficient real-time performance of complex 3D models. The framework has been developed and tested, preliminarily verifying its feasibility, efficiency, and effectiveness.