Stability Prediction Based Effect Analysis of Tool Orientation on Machining Efficiency for Five-Axis Bull-Nose End Milling

2018 ◽  
Vol 140 (12) ◽  
Author(s):  
Xiaowei Tang ◽  
Zerun Zhu ◽  
Rong Yan ◽  
Chen Chen ◽  
Fangyu Peng ◽  
...  
Keyword(s):  
Stability Analysis ◽  
Prediction Model ◽  
Coordinate System ◽  
End Milling ◽  
Parameters Optimization ◽  
Machining Efficiency ◽  
Stability Prediction ◽  
Tool Orientation ◽  
Cutting Depth ◽  
Five Axis

The traditional stability analysis by only considering cutting depth-spindle speed lobe diagram is appropriate for parameters optimization and efficiency improvement of the five-axis ball-end milling. However due to the complicated cutter-workpiece engagement (CWE) of bull-nose end cutter in five-axis milling, the maximal cutting depth may not produce the maximal material removal rate (MRR). Thus, the traditional stability analysis is not suitable for the five-axis bull-nose end milling in parameters optimization, and this paper presents a new stability analysis method to analyze the effect of tool orientation on machining efficiency for five-axis bull-nose end milling. In the establishing of stability prediction model, coordinate transformation and vector projection method are adopted to identify the CWE and dynamic cutting thickness, and the geometrical relationship of frequency response function (FRF) coordinate system and cutting force coordinate system with variable tool orientation is derived to establish the conversion of FRF and cutting force in stability equation. Based on the CWE sweeping, the cutting area along the feed direction is calculated to realize the critical MRR analysis in the stability model. Based on the established stability prediction model, the effects of tool orientation on critical cutting depth and MRR considering the chatter constraint are analyzed and validated by the cutting experiments, respectively. The lead-tilt diagram, which not only gives the boundary of stability region but also describes the contour line for MRR, is proposed for the further tool orientation optimization.

Dynamics and Stability Prediction of Five-Axis Flat-End Milling

2017 ◽  
Vol 139 (6) ◽  
Author(s):  
YaoAn Lu ◽  
Ye Ding ◽  
LiMin Zhu
Keyword(s):  
Cutting Force ◽  
End Milling ◽  
Stability Prediction ◽  
Tool Orientation ◽  
Cutting Force Prediction ◽  
Vector Method ◽  
Force Prediction ◽  
Flat End Milling ◽  
The Stability ◽  
Five Axis

The tool orientation of a flat-end cutter, determined by the lead and tilt angles of the cutter, can be optimized to increase the machining strip width. However, few studies focus on the effects of tool orientation on the five-axis milling process stability with flat-end cutters. Stability prediction starts with cutting force prediction, and the cutting force prediction is affected by the cutter-workpiece engagement (CWE). The engagement geometries occur between the flat-end cutter and the in-process workpiece (IPW) are complicated in five-axis milling, making the stability analysis for five-axis flat-end milling difficult. The robust discrete vector method (DVM) is adopted to identify the CWE for flat-end millings, and it can be extended to apply to general cutter millings. The milling system is then modeled as a two-degrees-of-freedom spring-mass-damper system with the predicted cutting forces. Thereafter, a general formulation for the dynamic milling system is developed considering the regenerative effect and the mode coupling effect simultaneously. Finally, an enhanced numerical integration method (NIM) is developed to predict the stability limits in flat-end milling with different tool orientations. Effectiveness of the strategy is validated by conducting experiments on five-axis flat-end milling.

Tool Orientation Planning in Milling With Process Dynamic Constraints: A Minimax Optimization Approach

2018 ◽  
Vol 140 (11) ◽  
Author(s):  
Tao Huang ◽  
Xiao-Ming Zhang ◽  
Jürgen Leopold ◽  
Han Ding
Keyword(s):  
Tool Path ◽  
End Milling ◽  
Tool Path Generation ◽  
Optimization Approach ◽  
Path Generation ◽  
Tool Orientation ◽  
Minimax Optimization ◽  
Ball End Milling ◽  
Dynamic Constraints ◽  
Five Axis

In five-axis milling process, the tool path generated by a commercial software seldom takes the dynamics of the machining process into account. The neglect of process dynamics may lead to milling chatter, which causes overcut, quick tool wear, etc., and thus damages workpiece surface and shortens tool life. This motivates us to consider dynamic constraints in the tool path generation. Tool orientation variations in five-axis ball-end milling influence chatter stability and surface location error (SLE) due to the varying tool-workpiece immersion area and cutting force, which inversely provides us a feasible and flexible way to suppress chatter and SLE. However, tool orientations adjustment for suppression of chatter and SLE may cause drastic changes of the tool orientations and affects surface quality. The challenge is to strike a balance between the smooth tool orientations and suppression of chatter and SLE. To overcome the challenge, this paper presents a minimax optimization approach for planning tool orientations. The optimization objective is to obtain smooth tool orientations, by minimizing the maximum variation of the rotational angles between adjacent cutter locations, with constraints of chatter-free and SLE threshold. A dedicated designed ball-end milling experiment is conducted to validate the proposed approach. The work provides new insight into the tool path generation for ball-end milling of sculpture surface; also it would be helpful to decision-making for process parameters optimization in practical complex parts milling operations at shop floor.

A Real-Time C3 Continuous Tool Path Smoothing and Interpolation Algorithm for Five-Axis Machine Tools

2020 ◽  
Vol 142 (4) ◽  
Author(s):  
Qin Hu ◽  
Youping Chen ◽  
Xiaoliang Jin ◽  
Jixiang Yang
Keyword(s):  
Coordinate System ◽  
Real Time ◽  
Machine Tools ◽  
Tool Path ◽  
Maximum Deviation ◽  
Interpolation Algorithm ◽  
Tool Orientation ◽  
Path Smoothing ◽  
Tip Position ◽  
Five Axis

Abstract Local corner smoothing method is commonly adopted to smooth linear (G01) tool path segments in computer numerical control (CNC) machining to realize continuous motion at transition corners. However, because of the highly non-linear relation between the arc-length and the spline parameter, and the challenge to synchronize the tool tip position and tool orientation, real-time and high-order continuous five-axis tool path smoothing and interpolation algorithms have not been well studied. This paper proposes a real-time C3 continuous corner smoothing and interpolation algorithm for five-axis machine tools. The transition corners of the tool tip position and tool orientation are analytically smoothed in the workpiece coordinate system (WCS) and the machine coordinate system (MCS) by C3 continuous PH splines, respectively. The maximum deviation errors of the smoothed tool tip position and the tool orientation are both constrained in the WCS. An analytical synchronization algorithm is developed to guarantee the motion variance of the smoothed tool orientation related to the tool tip displacement is also C3 continuous. The corresponding real-time interpolation method is developed with a continuous and peak-constrained jerk. Simulation results verify that the maximum deviation errors caused by the tool path smoothing algorithm are constrained, and continuous acceleration and jerk of each axis are achieved along the entire tool path. Comparisons demonstrate that the proposed algorithms achieve lower amplitude and variance of acceleration and jerk when compared with existing methods. Experiments show that the proposed five-axis corner smoothing and interpolation algorithms are serially executed in real-time with 0.5-ms cycle.

A Prediction Model of Surface Roughness in Micro End Milling

2015 ◽  
Vol 727-728 ◽  
pp. 354-357
Author(s):  
Mei Xia Yuan ◽  
Xi Bin Wang ◽  
Li Jiao ◽  
Yan Li
Keyword(s):  
Surface Roughness ◽  
Prediction Model ◽  
Feed Rate ◽  
End Milling ◽  
Orthogonal Experiment ◽  
Cutting Speed ◽  
Cutting Parameters ◽  
Micro Milling ◽  
Cutting Depth ◽  
Micro End Milling

Micro-milling orthogonal experiment of micro plane was done in mesoscale. Probability statistics and multiple regression principle were used to establish the surface roughness prediction model about cutting speed, feed rate and cutting depth, and the significant test of regression equation was done. On the basis of successfully building the prediction model of surface roughness, the diagram of surface roughness and cutting parameters was intuitively built, and then the effect of the cutting speed, feed rate and cutting depth on the small structure surface roughness was obtained.

Cutter Radius Compensation for Five- Axis Peripheral Milling in CNC System

2011 ◽  
Vol 317-319 ◽  
pp. 1979-1982
Author(s):  
You Dong Chen ◽  
Tian Miao Wang
Keyword(s):  
Coordinate System ◽  
Tool Orientation ◽  
Cnc System ◽  
Peripheral Milling ◽  
Kinematics Model ◽  
Computation Procedure ◽  
Radius Compensation ◽  
Five Axis

This paper presents a 3D tool radius compensation for five- axis peripheral milling in CNC systems. Using a generalized kinematics model of five- axis machines and uniform algorithm, it is possible to calculate the complete analytical equations for the tool orientation relative to part. The tool orientation relative to part selecting as Z-axis is used to establish compensation coordinate system. The points in the machine coordinate system are converted to the compensation coordinate system. The compensation points in the compensation coordinate system using these points can be calculated. This computation procedure is similar to the calculation of cutter compensation C. The compensation points in machine coordinate system can be obtained by converting the compensation points in the compensation coordinate system to machine coordinate system. The presented methodology was used in the CNC system, which makes the CNC system more efficiently and systematically

Experimental Study on Ball-End Milling of C/C Composite

2013 ◽  
Vol 650 ◽  
pp. 139-144
Author(s):  
Chen Wei Shan ◽  
Ying Zhao ◽  
Dong Peng Cui
Keyword(s):  
Prediction Model ◽  
High Speed ◽  
End Milling ◽  
Orthogonal Experiment ◽  
Carbon Matrix ◽  
Milling Process ◽  
Cutting Depth ◽  
Milling Force ◽  
Ball End Milling ◽  
Milling Forces

Along with the development of high speed machining technology, the ball end milling cutter’s application is more and more widely. An influence of four control parameters, namely feed, cutting depth, spindle speed and cutting width, on cutting forces is investigated. This paper focuses on experimental research of milling process of carbon fiber reinforced carbon matrix composite (C/C composite). The milling force prediction model for milling of composite using the carbide ball-end tools is built by orthogonal experiment. The experiment results show that : the reliability of the this prediction model is quite high, and the effect of milling speed on milling force is not very obvious, but the milling force increases with the increment of feed per tooth, milling depth and milling width. Using this information, a new prediction model for the milling forces is proposed that can be used for C/C composite milling.

An updated model of stability prediction in five-axis ball-end milling

2019 ◽  
Vol 103 (9-12) ◽  
pp. 3293-3306 ◽  
Author(s):  
Yuebang Dai ◽  
Hongkun Li ◽  
Jianglei Dong ◽  
Qiang Zhou ◽  
Jianhua Yong ◽  
...  
Keyword(s):  
End Milling ◽  
Stability Prediction ◽  
Ball End Milling ◽  
Five Axis
Sign in / Sign up

Export Citation Format

Share Document