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The steel ball surface defect is one of the main reasons for affecting bearing performance. It is very necessary to recognize the defects from steel ball surface images. Sematic segmentation is a vital step in recognition. Therefore, a new method for steel ball surface defect segmentation is presented. The method which used pre-trained U-Net model based on deep transfer learning and could extract objective features. The results showed that the values of MPA and MIoU are 0.7533 and 0.8431, respectively. It demonstrates that the presented method is better than others.

Dolphins have a strong ability of target identification in the ocean, how to use it has become a new field of exploration.It is mainly divided into three categories in the research of dolphin communication signals namely whistle, click and emergency signals. Dolphin Click sound is mainly used for target detection and recognition. In this paper, the research group designed a pool experiment to obtain the click signal when dolphin identify rubber bar, reef, aluminum bar and steel ball, and analyzes the signal form, frequency, spectrum change rule and other information from the perspective of time domain and time-frequency domain. The number of sine waves in click signal is analyzed when dolphins identify four kind of targets. We summarize six kinds of spectrum forms to classify the acquired acoustic signals, the probability of each spectrum form is analyzed and counted when dolphins detect and identify different targets.The results show that the click signal emitted by dolphins in target recognition is mainly one waveform click signal. The main energy of the frequency is concentrated at 0-200khz.

By adding cable devices to common Pot bearings or Steel ball bearings creatively, cable sliding friction aseismic bearings (CSFAB) could not only have the advantages of sliding friction isolation bearings, but also overcome the defect of the sliding friction isolation bearings, which could avoid the unseating of girder during earthquake. Further development of CSFAB is proposed in this paper, by adding "cable-spring" system to conventional CSFAB. This new type of CSFAB is referred to as CSFAB with buffer. The feasibility of the CSFAB with buffer is verified by prototype of the bearing and corresponding pseudo-static test. The actual performance of the bearing is in good agreement with the theoretical model.

PVDF piezoelectric film has high natural frequency, piezoelectric constant, fatigue resistance and impact resistance, which is especially suitable for measuring dynamic impact load. The sensor is used to monitor the cold heading process of the steel ball, which improves the production automation level, the processing quality and service life of the steel ball. In this paper, the kinematics model is established based on the actual steel ball cold heading machine. The steel ball cold heading model is established by DEFORM, and its simulation analysis is carried out. According to the simulation, the change law of cold heading force under the influence of different parameters is obtained. It proves that the data measured by the three-dimensional force sensor can judge the defects of cold heading and lay a solid foundation for the application of the three-dimensional force sensor to the production of steel ball cold heading.

In this paper, the dynamic mathematical model of semi-autogenous (SAG) mill system is studied through the experimental investigation and rational analysis on the basis of the actual situation in SAG mill factories. The model structure is based on conventional non-stationary population balance approach. The obtained model can sufficiently reflect the system characterization, features and functions. Based on the dynamic model, we can predict the states of SAG mill system such as load position, power, steel ball quantity etc. and design control strategies to make SAG system work in a more efficient way.

This study presents a novel molding/encapsulation/integration approach to realize tactile-bump and sensing-interface for the inductive tactile sensor (Figs.1a-b). Two sensing-interfaces are available using wafer-level silicon molding for proposed tactile sensor: (1) chrome steel ball encapsulated in polymer tactile bump (Fig. 1a), (2) MPC (Magnetic Polymer Composite) embedded in polymer tactile bump (Fig. 1b). Figs.1c-d show the design and sensing scheme of the proposed inductive tactile sensor. The proposed molding/encapsulation/integration approach offers three merits for the inductive tactile sensor: (1) chrome steel ball self-assembled/fixed in Si cavity for polymer molding, (2) tactile-bump and MPC sensing-interface integrated in Si cavity by polymer molding, and (3) polymers of different properties (e.g.: stiffness, magnetic property) integrated using multi-steps molding processes. The inductive tactile sensor of three different designs is successfully demonstrated.

There are presented the results of analyzing literature sources and production experience for the choice of materials for face impulse seal rings (FIS) as well as basic requirements for manufacturing and operating thereof. It has been substantiated a need in manufacturing FIS rings made of alternative less expensive but not less qualitative materials. To carry out the research, there was chosen 38X2MIOA steel as a material for manufacturing FIS rings, the specimens of which were strengthened by ion nitriding (IN) and carbonitriding (CN) methods. At strengthening 38X2MIOA steel by the methods of IN and CN, the thickness of the strengthened layers reaches 500 microns, and their microhardness does up to 10,000 MPa. As a result of tribological studies, it has been stated that for all the series of the samples with increasing the loads there are increased the friction forces; At increasing a load up to 9.81 N, the coefficient of friction first increases, and then decreases; Friction of a steel ball moving over the surface of disks made of 38X2MIOA steel is accompanied with a slight wear, which is characteristic for normal friction.

Bearing capacity and sensitivity are two important indicators of force sensor measurement performance. In this paper, the parameters optimization and performance analysis of the piezoelectric film force sensor for steel ball cold heading machine are carried out for the piezoelectric film force sensor for detecting cold ball force of steel ball. In order to avoid local stress concentration, a modified scheme of the structure of the piezoelectric film force sensor is proposed. A finite element model of the sensor was established, and then the main parameters affecting the bearing capacity and sensitivity of the sensor were simulated and optimized. The size of the sensor stress concentration area was analyzed. Finally, the optimized size parameters of the piezoelectric film force sensor were obtained, which improved the sensor sensitivity and its load capacity

In this paper, we consider a control problem of a ball and beam system in a situation where feedback is disconnected. Due to feedback disconnection, any feedback controller is not available and as a result, the position of the steel ball cannot be hold for long. The main difficulty is the open-loop environment at the happening of feedback disconnection. We show that bang-bang control input can be a good candidate which holds the ball position with certain bounds for the longest time.

This study designs a new type of elastic separation guiding mechanism made up of the elastic rod and the steel ball. The mechanism can be used into the long stroke separation of missile and take full advantage of the elastic rod's damping effect to reduce the relative deflection and collision probability of the separation bodies. A mathematical model regarding the guiding mechanism and the separation process has been established in this paper to detect the influence of the stiffness coefficient and the preload force of the guiding mechanism having on the separation process. The simulation results demonstrate that both the stiffness coefficient and the preload force are very important for missile separation, and then we further obtain their optimal values in a certain stage separation process.

In traditional bearing steel ball production, there is no automatic monitoring or control system. As a result, the forming defects and faults in the production process could not be found by the traditional manual detection method. In order to address this challenge, an on-line monitoring and control system for bearing steel ball production is proposed in this paper. The proposed system takes advantage of WiFi and Internet of Things, and it includes cold heading equipment forming quality monitoring system and grinding ball equipment pressure automatic control system. The proposed solution provides intelligent control in real-time and non-contact mode with high precision, and it improves the quality of steel ball and the production efficiency.

In view of the steel ball examination domain particularity, the more effective neural network structure has been obtained through the theoretical analysis and the massive experiments. An algorithm of steel ball surface examination has been proposed based on the BP neural network in this paper. The images pre-treatment should improve the examination rate. Finally the examination system of steel ball is proposed based on neural network.

For the sake of researching the relationship between the velocity and quality of the steel ball and the morphology of broken vehicle windshield glass, a relationship model between the velocity and quality of the steel ball and the morphology of broken glass was established by image processing technology. Three different types of steel ball, in five different velocities are selected to simulate the collision process. The results show that, the concentration area of broken vehicle windshield glass is decided by the velocity and quality of the steel ball: the heavier the steel ball, the faster the velocity, then the larger the area; the morphology of broken vehicle is related to the velocity and quality of the steel ball: with the rise of the velocity and quality, the morphology from no trace, radial trace, sparse arc trace and radial trace to intensive arc trace and radial trace. Good idea is given to reconstruct the speed and quality of the collision objective based on the morphology of broken glass.

In this paper, an adaptive robust dynamic surface controller (ARDSC) is designed to position the steel ball of a magnetic levitation system. The proposed dynamic surface controller is utilized to overcome the problem of explosion of terms associated with the backstepping method. The presence of modeling errors that are uncertainties of physical parameters is considered in this paper. The adaptive mechanism can deal with the model uncertainties and the analysis of the control stability is given. Simulation results are included to indicate the effectiveness and robustness of the provided controller.

An automatic surface defect of Steel Ball detection system based on the CCD image processing technology has been designed. The system consists of automatic feeding stuff mechanism, feeding stuff expansion, defect recognition and sorted mechanism. We designed improved sabel algorithm for edge detection, and the modified medium filtering technology is used to eliminate noises, and the vector invariance method is applied to automatically divide threshold value. The system can run steadily for long time, and its results are reliable, and it overcomes disadvantages of conventional detecting methods such as high labor intensity and high misdetection rate. Measured data can be automatic acquisition, judgment, storage

In high-speed/high-precision ball screw transmitting systems, the re-circulating mechanism of ball screws is used for providing the path for steel balls rolling in screw grooves generally. Forces caused by the impact activity between the steel ball and re-circulating mechanism has resulted in a series of troublesome problems, such as violent vibration, strong noise, etc.. In order to investigate the impact-contact between the ball and re-circulating mechanism, a multibody dynamics model is proposed by using ADAMS and C++ language. And the simulation result is validated by comparing the result obtained from the test and calculated result. The conclusion is made that the multibody dynamics model gives a accurate prediction of dynamics of the steel ball. The simulation and experimental results show that the realeased elastical energy of the preload ball results in discrepancy of the measured frequency of steel ball impact with returner and the calculated results.

In high-speed/high-precision ball screw transmitting systems, the re-circulating mechanism of ball screws is used for providing the path for steel balls rolling in screw grooves generally. Because the rotating speed of the driven shaft in the mechanism has become higher and higher, forces caused by the impact activity between the steel ball and re-circulating mechanism has resulted in a series of troublesome problems, such as violent vibration, strong noise, and damage to the recirculating mechanism after some significant service times, etc. In order to reduce the impact, a novel method using elastic joint between re-circulating mechanism and nut is proposed and the influence of joint rigidity on impact force is discussed. The conclusion is made that the impact force using rigid joint is always higher than that using elastic joint, and the influence degree of joint rigidity on the impact force is affected by the mass radio of steel ball and re-circulating mechanism. The experimental results show that using elastic joint between re-circulating mechanism and nut can reduce the impact force effectively.

In order to lengthen the service life of artificial organs ,blood can be used as lucricant in artificial organs.For the purpose of studying on the influenced factors to blood lubricating properities,espcially how much the component of blood can affect blood lubricating properities. In this paper, the blood lubricating properities of four kinds of hematocrit were studied by the frication tester. The worn spots and the adsorption films formed on the steel ball were observed through the Leica DMI 5000M material Microscope. It was founed that : (1) the microshape of the lubricant film depends on the hematocrit;(2) the higher blood's hematocrit is, the smaller worn spots formed on the steel ball become. It is concluded that the higher the hematocrit is, the larger the lubricant film's bearing capacity appears.

A ball screw driven mechanism is a major component in high-speed/high-precision transmitting systems. In such a mechanism, the re-circulating mechanism has been designed to provide the path for steel balls rolling in screw grooves. As the driven shaft in the mechanism operates at high rotating speed, forces caused by the impact activity between the steel ball and re-circulating mechanism may induce violent vibration and strong noise and cause damage to the re-circulating mechanism after some significant service times. In order to reduce the impact, a method using elastic joint between re-circulating mechanism and nut is proposed and the influence of joint rigidity on impact force is discussed. From results obtained here, it is shown that the impact force formed at rigid joint is always higher than that formed at elastic joint, and the influence degree of joint rigidity on the impact force is affected by the mass radio of steel ball and re-circulating mechanism. The experimental results indicate that using elastic joint between re-circulating mechanism and nut can reduce the impact forces effectively.

The structure and transmission principles of non-clearance cycloid steel ball planetary transmission are introduced in this paper. The complicated spatial mechanics model for multi-steel ball (multi-point contact of each ball) engagement pairs of the cycloid groove and ring groove are established. The maximum acting force formulas of the cycloid groove engagement pair and the ring engagement pair are deduced by using ultra static distort harmony conditions. The contact fatigue stresses of the cycloid groove and the ring groove engagement pairs are analyzed and the stress variety curves are plotted. The research results provide theoretical basis for the design of non-clearance cycloid steel ball planetary transmissions.

A characteristic evaluation method from an image of impact perforation process by a high speed photograph system has been studied in the material engineering field. In this method, a steel ball is shot into a material specimen to evaluate characteristics by observing the ball and fragments of the specimen. However, it is often difficult to find a steel ball because of the dispersion of fragments. In this study, we propose to use the self-organizing map to distinguish a steel ball, background and fragments.

This paper describes how requirements on transformer oil are reflected by different specified physical and chemical parameters of oil. Impulse breakdown is not included in many specifications but ASTMD3487 does have it. Breakdown behaviour with DC impulses and a heterogeneous gap is very different from the AC breakdown strength. It is designed to simulate lightning pulse striking during a thunderstorm. The result is independent of the contaminants influencing normal breakdown test. A needle and steel ball are used as electrodes, at a distance of 2.5 cm. With a negative impulse to the needle, the breakdown has been found to depend on the degree of oil refinement, with lower aromatic content giving a better/higher value. The most common refining processes are described.

CNx showed ultra low friction that friction coefficient was less than 0.01 sliding against Si/sub 3/N/sub 4/ ball in Nitrogen. However it can not show low friction in air. In order to obtain low friction of CNx coating sliding against stainless steel in air, we applied DC electric voltage to stainless steel. As a result, we showed the possibility of decreasing friction and wear of CNx sliding against stainless steel. Friction coefficient decreased with the increasing negative voltage to apply to the ball and disk in air. On the other hand, positive voltage increased friction coefficient. Friction coefficient of CNx in air decreased from 0.22 to 0.05 by applying electric voltage of DC -200 V. Specific wear rate was decreased with the increasing applied positive and negative voltage. Specific wear rate of CNx in air decreased from 2.86/spl times/10/sup -8/ mm/sup 3//Nm to 1.10/spl times/10/sup -8/ mm/sup 3//Nm by applying electric voltage of DC -200 V.