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Silicon carbide (SiC) particle-reinforced aluminum matrix (SiCp/Al) composites have continuously increased applications in abundant industries due to their superior mechanical properties. However, such composites have issues achieving desired machinability and quality standard due to the presence of SiC particles which is the main hindrance to their applications. In this paper, the methodology of ultrasonic vibration-assisted helical grinding (UVHG) of SiCp/Al composites has been applied to achieve to desired quality and efficiency for such composites. Then a mechanical cutting force model was developed to predict grinding forces. The grinding force was separated into friction force, plastic deformation force, and fracture force on account of the material removal mechanism. The undeformed chip thickness and cross-sectional area were calculated for the grinding force of a single diamond abrasive grit and then extended to the whole tool. By considering the acoustic softening effect of reduction of deformation stress caused by ultrasonic vibration, the acoustic softening coefficient was first proposed in the model to correct the impact of the ultrasonic vibration for properties of SiCp/Al composites. The experimental machining (UVHG) was carried out considering the different groups of experiments. The experimental results found agreed with the predicted values of cutting forces. The prediction deviation of the model was 7.06%, which could provide further guidance for the grinding process optimization of SiCp/Al composites. The novel cutting force predicted model and proposed machining methodology could be applied to machining SiCp/Al composites at the industry level and further research work.

Droplet injection methods are widely used in the applications of microelectronic manufacturing, biological engineering, and 3-D printing. This work presents a new jet dispenser driven by a single piezoelectric stack that enables the capability of drop-on-demand patterning under a high working frequency (500 Hz). Due to the special designs of the jet dispenser, a broad range of liquids, whose viscosities span more than four orders of magnitude (21-665 320 cps), can be jetted. Moreover, a coupled Coulomb damping physical model is proposed, which includes an electromechanical and a dynamic model. Both the Coulomb and the fluid-solid damping are considered in the dynamic model. In order to validate the results obtained by using MATLAB/Simulink, the experiments were carried out. The injection performance of this jet dispenser has been tested by employing a self-made jetting platform. The minimum volume of a jetting droplet is about 14.4 nL with liquid wax. The error of volume uniformity among droplets does not exceed 8%, and the error of angle trajectory is about 0.17°. Furthermore, the versatility of the jet dispenser is demonstrated by printing liquid lubricant, food, glue, silver past, and a ceramic slurry in predefined patterns.

Due to the fast response, high precision and high working frequency, needle driven piezoelectric micro-jet devices have been applied in various industrial fields. The injection performance is important for the applications. The jetting velocity of the micro-droplets has a great influence on the ligament length and satellites. In this paper, the Fluent stimulation model of dynamic mesh motion has been established to simulate the jetting process. Meanwhile, the dependences of volume and jetting velocity of micro-droplets on input signal, including voltage, falling time, and fluid pressure, have been studied. The results show that the jetting velocity of micro-droplets can be changed and the volume is invariant by adjusting falling time, which can be used to guide the control of the needle driven piezoelectric micro-jet devices. Furthermore, the experimental system has been designed and the experiments show that the average minimum jetting velocity is about 0.724 m/s. The ligament length increases almost linearly with jetting velocity of the micro-droplets. And the optimal jetting velocity is less than 2.745 m/s, which cannot generate satellites.

Minimum quantity lubrication (MQL) is an eco-friendly cooling and lubricating method that has its importance in machining sustainability. However, the behavior of the MQL droplets remains questionable. The present study is conducted to investigate the penetration performance of MQL with different combination of spray parameters and capillary sizes. An observation platform has been designed, which makes the overall penetration process controllable. The results have shown that the shortest penetration time was obtained with larger capillary size, higher air flow rate and the corresponding smaller droplet size. However, the increase of air flow rate has the optimal value when the objective is to penetrate to 1 mm deep from the entrance, whereas it has not shown the similar regulation when the droplet flowed deeper to the center due to the long transport distance has amplified the effects of multiple influence factors. The observation results were verified through simulation and cutting experiment.

Ceramic matrix composites of type C/SiC have great potential because of their excellent properties such as high specific strength, high specific rigidity, high-temperature endurance, and superior wear resistance. However, the machining of C/SiC is still challenging to achieve desired efficiency and quality due to their heterogeneous, anisotropic, and varying thermal properties. Rotary ultrasonic machining (RUM) is considered as a highly feasible technology for advanced materials. Cutting force prediction in RUM can help to optimize input variables and reduce processing defects in composite materials. In this research, a mathematical axial cutting force model has been developed based on the indentation fracture theory of material removal mechanism considering penetration trajectory and energy conservation theorem for rotary ultrasonic face milling (RUFM) of C/SiC composites and validated through designed sets of experiments. Experimental results were found to be in good agreement with theoretically simulated results having less than 15% error. Therefore, this theoretical model can be effectively applied to predict the axial cutting forces during RUFM of C/SiC. The surface roughness of the workpiece materials was investigated after machining. The relationships of axial cutting force and surface roughness with cutting parameters, including spindle speed, feed rate, and cutting depth, were also investigated. In order to identify the influence of cutting parameters on the RUFM process, correlation analysis was applied. In addition, response surface methodology was employed to optimize the cutting parameters.

Ceramic matrix composites of type C/SiC have great potential in space applications because of their superior properties such as low density, high wear resistance, and high-temperature resistance. However, due to their heterogeneous, anisotropic, and unstable thermal properties, the machining is still challenging to achieve desired efficiency and quality. For advanced materials, rotary ultrasonic machining (RUM) is considered as a highly efficient technology. Predicting mechanical load in RUM can help to optimize input variables and reduce processing defects in composites. In this research, a mathematical axial drilling load (force and torque) model has been developed based on the indentation fracture theory of material removal mechanism considering penetration trajectory and energy conservation theorem for rotary ultrasonic drilling (RUD) of C/SiC. Experiments were conducted on C/SiC composites to validate the model, and experimental results agreed well with model predictions with less than 14% (force) and 10% (torque) error. Therefore, this theoretical model can be effectively applied to predict axial drilling load during RUD of C/SiC. The relationships of axial drilling force and torque with machining process parameters, including spindle speed, feed rate, and ultrasonic power, were investigated. A specific range of experiments was carried out to demonstrate the benefit of ultrasonic vibration in RUD over conventional drilling (CD) on mechanical load for a designed drilling tool. It was noticed that RUD outperformed CD with a maximum of 38.11% and 34.30% in axial drilling force and torque reduction, respectively. The influence of drilling tool flute length on drilling performance was also elucidated based on a set of experiments using several designed drilling tools.

SiCf/SiC composites have been applied in numerous fields because of their outstanding properties like high specific strength and high specific modulus. However, defects can be produced during grinding because the composites are hard and brittle. Moreover, the fabrication process of laminated SiCf/SiC composites is complicated and unstable, resulting in large differences in their elastic properties. Therefore, the effective elastic properties of composites needs to be obtained through theoretical analysis. In this study, the anisotropy of orthogonal laminated SiCf/SiC composites and the fracture removal mechanism of the brittle material were both considered to develop a more accurate model. The effective elastic constants of the laminated composites were calculated using a macromechanical analysis. The grinding process was divided into the ductile, ductile-to-brittle transition, and brittle stages for analysis by the critical cutting depth. The modeling development was based on the interaction between the diamond grains and workpiece. Substituting the effective elastic constants into the model, the predicted value is consistent well with the experimental value. The cutting force value presents a non-linear decreasing trend with increasing spindle speed but increases linearly with increasing feed rate and cutting width. The spindle speed and cutting width have more influence on the cutting force than the feed rate. Increasing the spindle speed and decreasing the feed rate and cutting width can reduce the cutting force. The model can be applied to adequately evaluate the effective elastic properties of laminated SiCf/SiC composites and effectively improve the grinding processes and machining efficiency in future applications.

Cutting force has a great effect on the machining surface/subsurface damage. The prediction model of cutting force is necessary to optimize input variables. During rotary ultrasonic side grinding (RUSG), the indentation depth of a single abrasive grain increases (up milling) from 0 to maximum or decreases (down milling) from maximum to 0 with the motion of abrasive grains. Therefore, the ductile removal mode and brittle fracture removal mode coexist. In this research, a mechanistic cutting force model in RUSG of carbon fiber–reinforced polymer (CFRP) composites, considering both brittleness and ductility, has been developed for the first time. The ductile-brittle ratio K has been put forward and obtained through experiments. The cutting force perpendicular to feed direction has been calculated by integration method from the point of force analysis. The results showed that K increases with the rise of spindle speed or the decrease of feed rate and cutting width. The cutting force behaves oppositely with respect to K. Finally, orthogonal experiments have been conducted to verify the cutting force model and the results show good consistency between theoretical cutting force and measured cutting force. The developed model is capable to predict the cutting force in RUSG of CFRP composites and provides a support for optimizing the process.

Materials jetting, known as one of the 3D printing technologies, is widely applied in microelectronics packaging, biology and ceramic 3D printing due to its ability to print multi-materials by drop-on-demand. However, most of the materials are power-law fluids in 3D printing applications, the generation of satellites during the jetting process and droplet spreading characteristics are unclear and they have a great effect on the quality of the printout. In this paper, a common electromechanical and fluid-solid coupling model of the jet dispenser and observation platform of the jetting process are established. This modeling method is also suitable for other needle-driven jet dispensers. A commercial UV resin is adopted to study the jetting process of power-law fluid. To reveal the mechanism of satellite generation, the effects of input signals (rising time and falling time) on the dynamic characteristics of the needle and the jetting process are analyzed. On the basis thereof, the effectiveness of the optimal control parameters is demonstrated to eliminate satellites. In addition, the simulation and experimental results show that the falling time and fluid pressure can be controlled to adjust the spreading diameter and height of the droplet. Subsequently, the minimum line width of 0.276 mm is successfully printed with a nozzle of 0.07 mm.

In this study, a finite element model (FEM) of a single diamond grinding SiCf/SiC composites was established, and the process of ultrasonic vibration-assisted grinding was simulated and investigated from a microscopic perspective. The damage behavior and removal mechanism of ultrasonic vibration-assisted grinding along across fibers, longitudinal fibers, and transverse fibers were analyzed, respectively. Simulation results show that brittle fracture is the main removal mechanism of the matrix. The damage behavior of fibers mainly includes fiber breakage, fiber fracture, fiber pull-out, and fiber debonding. There are large differences in the removal mechanism of materials ground in different fiber directions. The simulation results provide important guidance for a better understanding of the damage behavior and removal mechanism of ultrasonic vibration-assisted grinding of SiCf/SiC composites.

The longitudinal and torsional ultrasonic machining (LTUM) is an emerging ultrasonic vibration machining method, which is an innovation method based on rotary ultrasonic machining (RUM). Compared with one-dimensional longitudinal ultrasonic machining (LUM), LTUM has better performances and promising applicability. In this research, the machining mechanism and a drilling force model in longitudinal and torsional ultrasonic vibration drilling is proposed based on kinematic analysis. Besides, the kinematic model and track model in LTUM are established. In addition, the dynamic characteristics and cutting characteristics of the abrasive grains in LTUM are analyzed. Meanwhile, the material removal model for fracture material based on the indentation fracture theory in LTUM is considered. Based on the kinematic analysis and material removal model in the longitudinal and torsional ultrasonic vibration drilling, the cutting force model is developed and the relationship of cutting force with processing parameters and material parameters is investigated. Eventually, the verification experiment is carried out on carbon fiber-reinforced polymer (CFRP)-T700. The experimental result shows that the developed cutting force model predicts the cutting force accurately and the deviation is less than 10% in CFRP drilling. Additionally, the drilling experiment of LTUM, LUM, and conventional drilling (CD) are carried out respectively, and drilling force in the three processes are compared. The comparative analysis results show LTUM is superior to LUM and CD with lower drilling force and better performance.

Minimum quantity lubrication (MQL) is the efficient and environmentally friendly technology, which is desirable to achieve sustainability during machining process. The nozzle distance has its significance in dominating the MQL spray and the related droplet transportation and penetration. In this paper, the nozzle distance has been optimized for MQL milling process through numerical and experimental methods. A two-way computational method has been employed to solve for the comprehensive flow field and particle trajectories, with the wall condition established on the spray impingement theory. The interactions of air flow rates and spindle rotational speeds on droplet penetration are investigated in details. The optimal ranges of nozzle distance setup obtained by simulation for different conditions were verified via slot milling tests, in which the nozzle distances were selected according to the key points obtained in the numerical process. The cutting force and surface roughness were recorded for the verification of adhesion ability and the related cutting performance. The comparison between numerical simulations and milling experiments has shown great consistency. This paper has achieved better understanding of the nozzle orientation setup and device development in MQL milling process, especially for external MQL. The theoretical basis and scientific instruction have been provided for the optimization of MQL operating parameters in industrial applications.

In order to simplify the motor structure, reduce the difficulty of modal coupling and obtain a wide driving frequency range, a new piezoelectric motor which works on the two second bending vibratio...

This paper is dedicated to the nanoscale machining simulation with the help of SPH method. The main goal of the research is to investigate the ductile mode machining of the brittle materials. The special scalar plasticity measure is introduced as a generic parameter of surface quality after machining. This measure can be used to describe the surface quality due to different machining modes and to analyze influence of fillet radius or cutting depth on the surface quality. As the SPH method deals with discrete particles, there is a problem of correct identification of those particles, which form the surface after machining. The special algorithm is proposed to solve this problem. Finally, the influence of the cutter fillet radius on the obtained plasticity measure is determined to be linear in considered range.

Ceramic matrix composites of type C/SiC with superior properties have got increasing importance in many fields of industry, especially in the aerospace area. Rotary ultrasonic machining is a high-efficiency processing technology for these advanced materials. However, due to the inhomogeneity and anisotropy of these composites, the machining process is still challenging to achieve desired result due to the lack of understanding and control of material removal mechanism. In this paper, the maximum depth of penetration by diamond abrasives in workpiece material is proposed to quantify the material removal modes. A model of maximum depth of penetration for rotary ultrasonic face machining (RUFM) was developed based on the indentation theory. An experimental RUFM of C/SiC was carried out, and it revealed that the material removal mechanism transited from ductile mode to brittle fracture mode with the decrease of cutting speed. Similar transition was observed with the increase of feed rate and cutting depth. By comparing the measured cutting force with simulation, a critical depth of penetration for the cutting mechanism transition was defined at about 4 μm. The processed surface topography was studied, and the transition of material removal modes was identified by the sudden change of the 3D surface roughness map at the critical penetration depth. Thus, the maximum depth of penetration model developed in this paper can be applied to identify the ductile or brittle fracture removal mode in RUFM of C/SiC using the cutting parameters. This allows controlling the material removal mechanism to achieve desired machining efficiency and quality.

Carbon fiber reinforced polymers (CFRP) have got rapidly increased applications in aerospace/aircraft and other fields due to their attractive properties of high specific strength/stiffness, high corrosion resistance, and low thermal expansion. These materials have also some challenging properties like heterogeneity, anisotropy, and low heat dissipation. Due to these properties, the issues of excessive cutting forces and machining damages (delamination, fiber pull-out, surface/subsurface defects, etc.) are encountered in machining. The cutting forces are required to be minimized for qualified machining with reduced damages. In this research, a novel cutting force prediction model has been developed for vibration-assisted slot milling. The experimental machining has been carried out on CFRP-T700 composite material. The effective cutting time per vibration cycle and the force of friction have been expressed/calculated. The feasibility of vibration-assisted machining for CFRP composites has also been evaluated. The relationships of the axial and feed cutting forces with machining parameters were investigated. The results have shown the variations below 10% among experimental and corresponding simulation values (from the model) of cutting forces. However, the higher variations have been found in some experiments which are mainly due to heterogeneity, anisotropy, and some other properties of such materials. The developed cutting force model then validated through pilot experiments and found the same results. So, the developed cutting force model is robust and can be applied to predict cutting forces and optimization for vibration-assisted slot milling of CFRP composite materials at the industry level.

Carbon fiber reinforced polymers (CFRP) have got widely increased applications in aviation, defense and other industries due to their properties of high specific strength/stiffness, high corrosion resistance and low-thermal expansion. The issues like excessive cutting forces and machining damages are encountered in machining due to heterogeneity, anisotropy and low heat dissipation of these materials. The cutting forces are required to be predicted/minimized through modeling. In this article, the novel axial and feed cutting force model has been developed and validated through rotary ultrasonic slot milling of CFRP composites. The variations less than 10% have been found between the measured and corresponding simulated values of the cutting forces. However, some higher variations have also been observed in the few cases mainly due to heterogeneity and anisotropy of such material. The cutting depth is a significant parameter for axial and feed forces, while the feed rate is significant for the axia...

Carbon fiber reinforced polymers (CFRP) have got paramount importance in aircraft, aerospace, and other fields due to their attractive properties of high specific strength/stiffness, high corrosion resistance, and low thermal expansion. These materials have also the properties of inhomogeneity, heterogeneity, anisotropy, and low heat dissipation which generate the issues of excessive cutting forces and machining damages (delamination, fiber pull out, matrix burning, etc.). The cutting forces are required to be modeled for their control/ minimization. In this research, a generalized cutting force model has been developed for rotary ultrasonic face milling of CFRP composites. The experimental machining was carried out on CFRP-T700 material. The cutting forces found decreased significantly with the increase of spindle speed while the same found increased with the increase of feed rate and cutting depth. The variation less than 10% has been found between experimental and simulated values (from the model) of cutting forces. However, the higher variation has also observed in the few groups of experiments due to the properties of inhomogeneity, heterogeneity, anisotropy, and low heat dissipation of such materials. The expression for the contact area of the abrasive core tools has been improved and an overlapping cutting allowance has been incorporated the first time. The developed cutting force model has been validated and found robust. So, the generalized cutting force model developed in this paper can be applied to control/minimize the cutting forces for rotary ultrasonic face milling of CFRP composite materials and optimization of the process.

Although superior in properties, composite materials still have problems in machining, such as delamination, cracking, burning, tool blockage, and cost and efficiency issues. These problems can prevent wide application of extraordinary composite materials. As an effective method in composite machining, rotary ultrasonic machining (RUM) process has been paid much attention to recently. The current studies on RUM tool design are mostly based on experiments. However, the insufficiency of RUM tool design theory would generally result in the tool blockage, which subsequently leads to the sharp increase in cutting force and poor machining quality in the engineer application. Besides, few investigations are made to combine tool design parameters with machining conditions to avoid tool blockage during RUM process. In this work, based on the RUM material removal mechanism, two models for the chip space and the chip length are built. Thus, the tool blockage condition in RUM is linked with the tool design parameters and the cutting parameters. Experimental study is performed for theoretical verification. Due to the differences in the modalities of the chip, two typical types of composites, C/SiC and CFRP T700, are selected to obtain their tool blockage conditions. The test results show that to prevent the occurrence of blockage, the chip space should be greater than the chip length in C/SiC milling, while in T700 milling, the chip space should be at least over 8 times greater than the chip length.

X-ray computed tomography (CT) is a widely popular nondestructive testing technique for engineering and medical purposes, but its limitation is openly recognized in the inspection of large components, particularly for plate-type structures. Computed laminography (CL) avoids this defect. Nowadays, most of the existing analytical CL reconstruction approaches ignore the problem that the projection data under the CL scanning structure does not strictly meet the conditions of the standard filtered back-projection (FBP) or Feldkamp–Davis–Kress (FDK) method. Since the original CL data are directly filtered without considering the influence of the tilt angle of the CL rotation axis, this will affect the quality of the reconstructed images. In view of this situation, a conversion method of cone-beam CL data based on projection transformation is proposed, which is also referred to as the CL re-projection (CLRP). The collected CL projections can be corrected to satisfy the filtering requirements. We establish a virtual CT detector and use the CLRP to convert the known CL data into the projection on the virtual detector. Then, the FDK method commonly used in cone-beam CT is applied to reconstruct the converted data. Through the above two steps to achieve CL reconstruction. Computer simulations and experimental results show that the CLRP algorithm can accurately convert the raw CL data into those which satisfying the FDK method. The CLRP can decline the information aliasing to a certain extent. Compared with the existing CL-FBP algorithm, the CLRP-FDK method for CL reconstruction can effectively reduce image artifacts. The CLRP algorithm provides a new idea for CL reconstruction and plays an important role in practical engineering applications.

Minimum quantity lubrication (MQL) is an efficient and sustainable technology, which has been considered to be an option of conventional flood cutting process. Even though MQL provides green solution for the cooling and lubrication function during machining, it brings about unendurable aeroacoustic jet noise from the high velocity spray. The acoustic pollution has seriously affected the operator's health and efficiency so that it should be paid much attention to. In this paper, with the utilization of microjets noise reduction concept, a noise cancellation accessory for MQL nozzle has been developed. The flow field and aeroacoustic characteristics of the original nozzle and microjets have been investigated numerically to help understand the noise reduction mechanism. Variables including the main jet flow rates, the air flow rate ratios of the microjets to the main jet and the measuring azimuths on noise directivities and sound pressure level (SPL) have been analysed. It has found the flow ratio is a critical parameter, which has an optimal value in regard to the main jet flux. The simulation results have been partially verified through OASPL measurement. The overall aeroacoustic noise reduction varied from 0.70 to 4.88 dB has been observed experimentally. Finally, the noise cancellation mechanism has been discussed from the flow field and the frequency characteristics points of view. The shrinking effect of microjet injection at appropriate air flow ratios has significantly narrowed the distribution of the turbulent intensity and reduced the SPL of low and medium frequency while increased that of the high frequency in specific directions. The overall amplitude of OASPL has been reduced. However, inappropriate air flow ratios will generate additional jet noise.

The optimal feedrate planning on five-axis parametric tool path with multi-constraints remains challenging due to the variable curvature of tool path curves and the nonlinear relationships between the Cartesian space and joint space. The methods for solving this problem are very limited at present. The optimal feedrate associated with a programmed tool path is crucial for high speed and high accuracy machining. This paper presents a novel feedrate optimisation method for feedrate planning on five-axis parametric tool paths with preset multi-constraints including chord error constraint, tangential kinematic constraints and axis kinematic constraints. The proposed method first derives a linear objective function for feedrate optimisation by using a discrete format of primitive continuous objective function. Then, the preset multi-constraints are converted to nonlinear constraint conditions on the decision variables in the linear objective function and are then linearised with an approximation strategy. A li...

Due to the approximation errors of interpolation methods in non-uniform rational b-spline (NURBS) interpolation, feed fluctuation is inevitable, which has great effects on the machining quality and should be minimized. Based on the idea of zero feed fluctuation, a polynomial equation-based interpolation method of NURBS tool path is proposed in this paper. Firstly, a polynomial equation with respect to the curve parameter increment is formulized according to the sampling step size, which is determined by the scheduled feedrate, acceleration, and jerk. Then, Newton’s method is utilized to solve the high-degree polynomial equation with taking both convergence rate and computational load. In order to improve the computing efficiency in real-time interpolation, a fast-evaluation and derivation algorithm is proposed, which uses the Taylor series expansion to accelerate the calculation of any order derivatives of NURBS. Simulations are conducted among the proposed method and the chord-tracking algorithm (CTA) method, and the results of each method are compared on the basis of computing time and feed fluctuation, which shows that the proposed method is better than the CTA method. Experiment is also conducted to verify the feasibility and applicability of the proposed method in practical application.

Feedrate planning is crucial for CNC systems to generate a smooth and fast movement, which is closely related to the machining quality and machining efficiency. In this paper, a new method for adaptive feedrate planning is proposed for parametric tool path with respecting geometric and kinematic constraints for CNC machining. The mathematic relationships between the prescribed constraints and tool tip feedrate are first formulated. Then the feedrate upper bound at any curve parameter is derived, and the tool path is adaptively discretized into discrete sampling positions and corresponding maximum feedrates are calculated. A linear mathematic model for linear programming is proposed to obtain the optimal square values of feedrates at each sampling position. After solving the linear model by a well-developed linear programming algorithm, the optimal feedrates at each sampling position can be calculated. Finally, the optimal discrete feedrate data are fitted to a smooth spline curve as the ultimate feedrate profile, which respects all prescribed constraints. Experiments are conducted on two parametric tool paths to show the merits of the proposed method. Results show that the proposed method are feasible and applicable, the generated feedrate profiles of the two tool paths respect all the prescribed constraints.

Feedrate fluctuation caused by approximation errors of interpolation methods has great effects on machining quality in NURBS interpolation, but few methods can efficiently eliminate or reduce it to a satisfying level without sacrificing the computing efficiency at present. In order to solve this problem, a high accurate interpolation method for NURBS tool path is proposed. The proposed method can efficiently reduce the feedrate fluctuation by forming a quartic equation with respect to the curve parameter increment, which can be efficiently solved by analytic methods in real-time. Theoretically, the proposed method can totally eliminate the feedrate fluctuation for any 2nd degree NURBS curves and can interpolate 3rd degree NURBS curves with minimal feedrate fluctuation. Moreover, a smooth feedrate planning algorithm is also proposed to generate smooth tool motion with considering multiple constraints and scheduling errors by an efficient planning strategy. Experiments are conducted to verify the feasibility and applicability of the proposed method. This research presents a novel NURBS interpolation method with not only high accuracy but also satisfying computing efficiency.

Despite of the studies in the last decades, there are still some gaps in understanding of the distinctive behaviors of orthogonal turn-milling. In order to improve the performance of this new technology, deeper investigations are required. This work deals with the mechanics in non-eccentric orthogonal turn-milling. The engaged areas of both side edge and end edge are analyzed. Then, the boundary conditions used to extract them are derived. The two sets of cutting force coefficients for the side edge and end edge are calibrated based on slot milling and plunge milling, respectively. The total cutting forces are calculated as a sum of the cutting forces on both side edge and end edge. The proposed cutting force model is validated experimentally on a five-axis machine tool. In addition, comparative experiments have been conducted to investigate the effects of cutting depth and longitudinal feed rate on the cutting force in tool axis direction.