NC System Research Articles

Subaru Near-infrared Imaging Polarimetry of Misaligned Disks around the SR 24 Hierarchical Triple System*

Abstract The SR 24 multistar system hosts both circumprimary and circumsecondary disks, which are strongly misaligned with each other. The circumsecondary disk is circumbinary in nature. Interestingly, both disks are interacting, and they possibly rotate in opposite directions. To investigate the nature of this unique twin disk system, we present 0.″1 resolution near-infrared polarized intensity images of the circumstellar structures around SR 24, obtained with HiCIAO mounted on the Subaru 8.2 m telescope. Both the circumprimary disk and the circumsecondary disk are resolved and have elongated features. While the position angle of the major axis and radius of the near-IR (NIR) polarization disk around SR 24S are 55° and 137 au, respectively, those around SR 24N are 110° and 34 au, respectively. With regard to overall morphology, the circumprimary disk around SR 24S shows strong asymmetry, whereas the circumsecondary disk around SR 24N shows relatively strong symmetry. Our NIR observations confirm the previous claim that the circumprimary and circumsecondary disks are misaligned from each other. Both the circumprimary and circumsecondary disks show similar structures in 12CO observations in terms of its size and elongation direction. This consistency is because both NIR and 12CO are tracing surface layers of the flared disks. As the radius of the polarization disk around SR 24N is roughly consistent with the size of the outer Roche lobe, it is natural to interpret the polarization disk around SR 24N as a circumbinary disk surrounding the SR 24Nb–Nc system.

АДДИТИВНО-СУБТРАКТИВНЫЕ ТЕХНОЛОГИИ - ЭФФЕКТИВНЫЙ ПЕРЕХОД К ИННОВАЦИОННОМУ ПРОИЗВОДСТВУ

At present a rapid development of additive technologies for the growth of metal and alloy products takes place. Each additive technology has its own rational field of application and its own characteristic set of advantages and disadvantages. The most promising technologies are new 3DMP-technologies of wire sedimentation/welding deposition by a method electric arc welding in combination with subtractive machining technologies (additive-subtractive technologies). The application of 3DMP-technologies in comparison with common and some powder technologies results in the considerable decrease of production costs and substantial increase of growth productivity, for them it is characteristic a high coefficient of initial material beneficial use. The advantage in use of additive-subtractive technologies (AST) consists in a possibility of the alternative use of additive and subtractive transitions at the formation of a part within the limits of one technological operation in a full compliance with the principle of community and constancy of technological bases. But AST peculiarity requires a complex solution of interrelated engineering and scientific problems including those in the field of design of products, material machining, engineering procedure automation and CAD systems. For instance, in consequence of that the realization of 3DMP-technology is possible only under conditions of complete process automation, in the presence of a subtractive module having 3-5 controlled coordinates, for the equipment on the whole the NC system is necessary which controls the execution unit displacement along six coordinate axes and more.

Thermodynamic model of the influence of temperature and carbon on the production of ferroalloy and calcium carbide from the basalt of Dubersay deposit

The article covers the results of researches on thermodynamic modeling of ferroalloy and calcium carbide obtaining from basalts of deposit Dubersay. The software package HSC-5.1, based on the principle of Gibbs energy minimum uses in the study. The influence of temperature (from 500 to 2500 °C) and the amount of carbon (from 40 to 60 % of the basalt mass) in the basalt–Fe–nC system was determined. It has been established that iron silicides are formed at T ≥ 1300 °C, Si at T ≥ 1400 °C, CaSi and Al at T> 1700 °C and CaC2 – at T ≥ 1800 °C. An increase of the amount of carbon from 40 to 60 % allows rise the degree of distribution of Si in the alloy up to 94 %, calcium in CaCl2 – up to 62.3 %, aluminum – to alloy up to 93.9 %. An increase of the amount of carbon allows increase the silicon concentration in alloy up to 55 % (at 1800 °C), aluminum – up to 17 % (at 2000 °C) and calcium carbide capacity – up to 350 dm3/kg. The method of rototable planning of the second order allows find equations of regressions of the influence of temperature and amount of carbon on the equilibrium distribution of silicon, aluminum, and calcium between the ferroalloy and calcium carbide. On the basis of this equations were determined, that within the temperature range 1956-1996 °C from the Dubersay deposit basalt, the ferroalloy with a content of ΣSi and Al 60.8-65.4 % (including 12- 15 % Si) and calcium carbide with a capacity of 250-300 dm3/kg are formed. Wherein degree of recovery into the alloy for silicon is 91-91.4 % and for aluminum is 63-75.1 % and calcium – into CaC2 is 60-60.7 %. The resulting ferroalloy by the content of silicon and aluminum can be attributed to the complex ferroalloy – ferrosilicoaluminium, calcium carbide – to the industrial product of grade from 3 and up to the highest.

Open and portable NURBS interpolator based on quantum framework

In order to solve the embedded NURBS interpolator closed structure problem, this paper proposes a NURBS interpolator based on quantum framework software bus architecture. Firstly, the NURBS interpolator trajectory interpolation algorithm and feedrate scheduling algorithm are presented. The embedded NC system systematic architecture is analyzed based on quantum framework. Secondly, the high-speed and high-precision NURBS curve interpolator and platform based on quantum framework are constructed. Finally, software simulation and actual machining experiment verify the correctness and validity of NURBS interpolator structure based on quantum framework by this paper.

An adaptive parameter optimization model and system for sustainable gear dry hobbing in batch production

Gear hobbing technology is one of the most widely used forming processes of gear teeth. And the development of dry hobbing technology provides a solution for realizing productive, economical, and ecological gear production. Since there is no cutting oil for cooling and lubrication in dry hobbing process, the hob tool life, thermal deformation errors of machine tool, and quality of workpiece are sensitive to the cutting parameters, especially the cutting speed and tip chip thickness. Considering this situation, a dry hobbing parameters optimization model with the hobbing efficiency as our objective, and the hobbing cost per piece, gear quality, tact time as constraints was established, in which the cutting speed and tip chip thickness were considered as optimal variables and the material of workpiece, coating of hob, and feed rate were considered comprehensively. An iterative test method is proposed to solve this model. And for the application in automated production line, an online adaptive application system was also developed based on SINUMERIK 840D NC system. The parameters of five different kinds of material gear were optimized by applying this model and system, and the result showed the model and the system were practical.

Motion Control System of NC Turret Punch Feeding Mechanism Based on Motion Control Card

According to the characteristics and requirements of NC turret punch feeding mechanism, the open NC system architecture is constructed based on the mode of PC and motion control card. The structure of hardware system is built with DMC1410 motion control card. The movement pattern of trapezoidal velocity curve and S velocity curve are analyzed. The flow chart and the software module of motion control system of NC turret punch feeding mechanism are presented. Under the support of MFC provided by VS2015 and movement function library provided by DMC1410 motion control card, the software of motion control system is developed.

Thermal error modeling and compensation of a heavy gantry-type machine tool and its verification in machining

In order to derive a thermal error model that can better reflect the physical model of the machine tool to improve the model’s robustness and also has an explicit and simpler expression for real-time thermal error compensation, a new thermal error model of a heavy gantry-type machine tool was established. Firstly, multi-body system (MBS) was used to transform the thermal error modeling of the machine tool into the thermal error modeling of the discrete parts of the machine tool. Then, as for the thermal error modeling of the slider-ram structure, by analyzing the characteristic of the thermal expansion of a one-dimensional rod, power function was considered to better reflect that relationship in which the index number can represent the distance between heat source and the temperature measurement location. Then, its thermal error model was expressed as the superposition of two power functions according to the thermal superposition principle and the distribution of the heat sources. As for the thermal error modeling of gantry structure, it was simplified to a frame with −3 DOF. And its thermal error model was derived by virtual work principle (VWP). Then, the whole thermal error model of the machine tool was embedded into the Simens840d NC system and S7-300 programmable logic controller to establish a thermal error compensation system. Finally, the error model and compensation was verified by machining a rhombus-shaped workpiece of which different zones reflect the thermal error in different directions. And the workpiece was measured by a CMM. The results show that the average thermal error can be reduced from around 101 to 13.5 μm after the compensation, indicating the effectiveness of the thermal error modeling and compensation for the practical application.

Tribological behaviour of an electrochemical jet machined textured Al-Si automotive cylinder liner material

This paper investigates the use of Electrochemical Jet Machining to surface texture a hyper-eutectic Al-Si cylinder liner material. Samples were lapped to a 6μm finish followed by immersion in 1mol NaOH to expose the primary silicon colonies above the aluminium surface. Texturing was carried out using a NC system comprising of a fine gauge nozzle (cathode) jetting a solution of 2.3mol NaCl on the surface (anode) whilst applying a current density of 220A/cm2. An array of hemispherical dimples at 1.5mm spacing was created, with an average diameter of 420μm and depth of 40μm, corresponding to an ε ratio of 0.095. Lubricated reciprocating sliding was carried out at stroke length of 25mm in a bath of PAO (4cSt) against a 52100 cylinder of 6mm diameter and 16mm length. Sliding frequencies were incremented at 1Hz intervals between 1–15Hz at 50N load increments from 50-200N. Stribeck curves indicated a reduction of the friction coefficient due to texturing of up to 0.05 in the mixed lubrication regime, representing a decrease of 38.5%. Optical profilometry and SEM indicated that abrasion and formation of a surface tribo-layer was mitigated in regions of the Al-Si surface where textured features were present parallel to the sliding direction.

Analysis and Research of High Speed Laser Cutting Machine Based on FVM

The structure of high speed CNC laser cutting machine is described, the deformation of the high speed laser cutting machine flying beam mechanism in the course of the campaign, FVM was used to analyze the deformation of the flying beam generated in different situations, according to the analysis results, put forward the method of NC system dynamics based on the inhibition of deformation to reduce flight. The deformation of the beam when high speed cutting purposes.

Ionic liquid incorporated nanocomposite polymer electrolytes for rechargeable lithium ion battery: A way to achieve improved electrochemical and interfacial properties

An ionic liquid incorporated nanocomposite electrolytes are prepared using solution cast technique by immobilizing a solution of lithium N,N-bis(trifluoromethanesulfonyl)imide (LiTFSI) in N-ethyl-N-methylimidazolium - bis(trifluoromethanesulfonyl) imide (EMImTFSI) ionic liquid (IL) with added mixtures of organic solvent and nanofiller such as acetonitrile and nanochitosan (32nm) into a poly(ethylene oxide) (PEO) matrix. The achieved extreme ionic conductivity of ionic liquid based electrolyte is in the range of 10⿿2Scm⿿1 which is one order higher than that of (PEO)8LiTFSI-10wt% NC system. Cyclic voltammetry and linear sweep voltammetry (LSV) analyses indicates that the prepared electrolytes possesses an excellent electrochemical stability of 3.9V. These unique properties allow the effective use of these membranes as active separators for the development of advanced lithium ion batteries.

Kinematic corner smoothing for high speed machine tools

This paper presents a novel kinematic corner smoothing technique for high-speed CNC machine tools. Typically, reference tool-paths compromised of short G01 moves are geometrically smoothed by means of arcs and splines within the NC system. In this study, a continuous feed motion is generated by directly planning jerk limited velocity transitions for the drives in the vicinity of sharp corners of the tool-path. This approach completely eliminates the need for geometry based path smoothing and feed planning. Contouring errors at sharp corners are controlled analytically by accurately calculating cornering speed and duration. Since proposed approach bases on kinematically planning axis motion profiles, it exploits acceleration and jerk limits of the drives and delivers a near-time optimal motion. Experimental validation and comparisons are presented to show significant improvement in the cycle time and accuracy of contouring Cartesian tool-paths.

Research on a Type of Program-Controlled Three-Dimensional Vibration Platform

Conventional mechanical vibration platform vibrates not only in the direction of back and forth but also in the direction of up and down. Vibrations in both directions are achieved by two mechanisms, respectively. Three-dimensional vibration cannot be realized. In this paper, the servo motor, the gear drive mechanism, and the parallel four-bar linkage mechanism are combined with the NC system. And a type of program-controlled three-dimensional vibration platform is designed. The platform can vibrate in three directions, such as the directions of up and down, left and right, back and forth. The parametric adjustment of amplitude and frequency in three directions can be realized. The vibration platform is suitable for high-speed and light-load three-dimensional vibration. Compared with the existing mechanical vibration platform, the designed vibration platform overcomes some deficiencies to realize three-dimensional vibration with variable frequency and amplitude.

Embedded PC On-Line Inspection System on NC Equipment

Based on open NC system architecture, embedded condition monitoring and diagnosis units were studied with the characteristics of modularization and reconfigurable. The intelligent measurement and control unit can be used to on-line monitoring, fault early warming, intelligent diagnosis and remote maintenance, it provied a solution for group integration monitoring system construction of high-grade NC machine. In this paper, the implementation and function of the intelligent measurement and control unit were introduced from 4 aspects including whole framework, hardware, software and XPE OS. An example of cutting force on-line monitoring were given, which operate well for alarming in unstable cutting condition.

Pipe Thread-Intelligent Detection and Restoration Technology

Regarding the problem for the existing CNC machining tube tip with the old car exists thread groove, on the basis of the mechanism analysis and experimental study, the detection of inherent inter-spindle screw thread cutting tracks with old spiral phase angle technology is herein proposed. Detected by the advanced hardware and software data processing technology, and strive to achieve the alignment tool for automatic restoration of the old spiral grooves machined technological breakthroughs, innovation and invention of the NC system turning tool with new features slot. Pipe thread repair machining accuracy and efficiency is significantly improved, which savelots of manpower and material resources.

Geometric error identification and compensation of linear axes based on a novel 13-line method

The geometric accuracy of linear axes lays a foundation for the machining accuracy of 5-axis machine tools. Although some geometric error identification and compensation approaches were developed for linear axes, the implementation efficiency and cost remain to be improved. In this paper, a novel 13-line identification method by using a laser interferometer is proposed, and the linear axes are compensated through the modification of compensation parameters in the NC system. The verification experiments are conducted through the tri-axial movement accuracy measurement and manufactured National Aerospace Standard test piece inspection, in which three circumstances, i.e., without compensation, with lead screw error compensation, and with error compensation based on the 13-line method, are compared. By using the 13-line method, the average accuracy of the tri-axial movement and test pieces are improved by 82.2 and 41.9 %, respectively, whereas the accuracy stability are improved by 77 and 46 %, respectively. Results show that the proposed identification and compensation method is effective and efficient.

An Approach to Building a Specialized CNC System for Laser Engraving Machining

An analysis of laser-dotted engraving technological specifics and laser-impulse machines control problems is presented. The main problem for material processing with impulse laser emission is the necessity to maintain the impulse frequency in a fixed interval. Any violation of this interval isn’t allowed, because it leads to significant energy dispersion between impulses and, as a result, to uneven material processing.The traditional control method with impulse confirmation waiting could be realized in any NC System. However, it leads to performance loss and incomplete use of machine capabilities. An approach is developed via impulse processing control based on the combination of advance NC blocks scanning method and speed profile adaptation for impulse frequency limit conditions.Experiments show that the developed approach allows to greatly increase the processing speed compared to the method with impulse confirmation waiting. The performance increase up to 30 – 50% is achieved; whilst the quality of processed details is maintained. The efficiency of the developed approach is supported by associated tools for the optimization and analysis of control program.

ПРИНЦИПЫ КОМПОНОВАНИЯ АВТОМАТИЧЕСКИ СМЕННЫХ ЛАЗЕРНЫХ МОДУЛЕЙ ПРИ РЕАЛИЗАЦИИ ТЕХНОЛОГИЙ ЛАЗЕРНОЙ ОБРАБОТКИ НА СТАНКАХ С ЧПУ

The article is devoted to the development of plug-in modules for automatically implementing the laser processing technology on CNC machines. At the heart of solutions used element base fiber lasers. Proposed technical solution of the device in which the optical system, the collimator and the laser emitter in the form of a single unit, composed of a single block, the parameters of each of which is determined by the requirements of the customer. When this module is replaceable and is working CNC machining cycles can be set in the tool magazine of the machine. The module is mounted in the spindle of the machine tool automatically stores the command NC system, and the radiation source is passed directly outside the working area of the machine. Communication with the module is provided by fiber optic cable. The proposed technical solution will be in demand in the market of industrial services, due to fold reduction in capital intensity, as there is no need to purchase a separate position of the laser center provides high performance and precision machining, no additional transportation and reinstallation of parts, reduced loss of time to process all the details. With reference to this article the methodology proposed are devices for laser treatment and are given based on the principle of modular build composition. The principle of modular build composition lies kinematic analysis devices, which allows, based on customer requirements, define a set of blocks for build composition device in the final state of delivery to the customer. The development of this device is the ability to study design at the stage of analysis and modernization of existing designs, and at the stage of preparation of the offer to the customer.

Research on CNC of FSW with Serial-Parallel Structure Based on 3-PRS Mechanism

With the increase of welding thickness, Friction stir welding equipment (FSW) with traditional milling machine structure could not meet the requirements of stiffness which to support the huge axis load. Therefore, a FSW with serial-parallel mechanism based on 3-PRS platform was proposed. In order to complete real-time control and the actual and virtual axis control of the equipment, the positive solution and inverse solution (based on Newton-Euler method) of the FSW are analyzed. Then, based on the PA system, the open CNC of the equipment is designed, and the inverse kinematics and the numerical positive kinematics based on Newton-Euler method are embedded into the interpolation of NC system. According to the demand of the equipment, human-machiner interface (HMI) is developed to display the positions of actual and virtual axis for the equipment, and compiler and interpolation are designed. At the same time, online real-time 3D motion simulation is designed, space pose of spindle and whole for the equipment are deduced. In the paper, design method of CNC based on the serial-parallel mechanism is provided.

A real-time and look-ahead interpolation methodology with dynamic B-spline transition scheme for CNC machining of short line segments

Tool path is presented as continuous small line segments in some existing NC machining programs. To achieve high machining speed and smooth machining quality, the tool path needs to be processed. This study presents a real-time and look-ahead interpolation methodology with dynamic B-spline transition scheme for short line segments machining. In the methodology, transition curve is adjusted to avoid intersection and keep high machining speed. Firstly, the unit length of every B-spline transition curve is calculated depending on tool path and NC system requirements; then, the maximum allowable velocity of the curve which is called threshold velocity can be got. Secondly, transition curve is determined according to the unit length and two consecutive threshold velocities, and time optimization function makes the transition curve take less machining time. Thirdly, the 7-phase velocity planning algorithm and static look-ahead algorithm are adopted to generate smooth machining feedrate and fine machining quality. Lastly, the curve interpolation is performed on the processed tool path. The simulations and experiments demonstrated that the proposed algorithm is able to achieve high machining speed and generate fine machining quality.

Realization of Signal Tone Detection in Power Line Carrier Terminal

—when the noise cancellation system ( NC ) is used in the down link of the power line carrier terminal, it can cancel the background noise and narrowband interference, but the downlink signal tone distorts at the same time. This is because the VAD algorithm of the NC system is sensitive to dramatic changes in the power of signal tone. Through detailed researches on time frequency characteristics of signal tone and error factors of network transmission, a new signal tone detection algorithm that applicable to downlink NC system was put forward, The algorithm detects signal tones through changes of frequency-domain power and time-domain signal period of every frame. After theoretical evaluation and practice tests, it is observed that the above-mentioned algorithm can correctly detect signal tones without influence on functions of the NC system, so as to avoid the occurrence of distortion.