Real-time smoothing of G01 commands for five-axis machining by constructing an entire spline with the bounded smoothing error

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.

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Research on 2-Dof Parallel Robot and its Motion Characteristics

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.139-141.2203 ◽

2010 ◽

Vol 139-141 ◽

pp. 2203-2206

Author(s):

Hui Ping Shen ◽

Lei Ding ◽

Chang Yu Xue ◽

Ju Li ◽

Jia Ming Deng ◽

...

Keyword(s):

Real Time ◽

Industrial Application ◽

Parallel Mechanism ◽

Parallel Robot ◽

Real Time Control ◽

Time Control ◽

Surface Welding ◽

Motion Characteristics ◽

Straight Lines ◽

Five Axis

A novel robot, derived from a planar parallel mechanism, is presented. With two sliders driving on the same side of parallel guide rails, this simple but practical mechanism is capable of realizing a large workspace. The direct and inverse kinematical solutions are given. The simulation demonstrates that all kinds of straight lines and circles can be realized by the end actuator of the robot; the corresponding motion disciplines and characteristics driven by the two sliders are analyzed; the results are verified on the prototype. By allowing the end actuator to move in Z-direction or to rotate around A or B-axis, three-, four-, five-axis manipulator would be composed and surface welding and space cutting would be realized. This paper lays the foundation for the real-time control and industrial application of this novel robot.

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RTCP Function in Five-Axis Machining

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.464.254 ◽

2011 ◽

Vol 464 ◽

pp. 254-259 ◽

Cited By ~ 3

Author(s):

Shu Tian Fan ◽

Wei Ping Yang ◽

Chao Jie Dong

Keyword(s):

Detailed Analysis ◽

Real Time ◽

Point Function ◽

Cnc System ◽

Rotary Axes ◽

Center Point ◽

Non Linear ◽

Rtcp Function ◽

Five Axis ◽

Time Linear

Because of the rotate kinematics, the machining of 5-axis brings up the non-linear error. The RTCP (Rotation Tool Center Point) function can always make the interpolated point on the programming track by a real-time linear compensation of CNC system for motion of the rotary axes. Based on detailed analysis of the kinematics principle of 5-axis machine with dual rotary tables, a new design of interpolated algorithm integrated with RTCP function is presented which is simulated in MATLAB, and the result indicates that the algorithm can reduce the non-linear error effectively.

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Study on Real-Time Compensation RTCP Module of Five-Axis CNC System

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.317-319.1662 ◽

2011 ◽

Vol 317-319 ◽

pp. 1662-1667 ◽

Cited By ~ 1

Author(s):

Ze Hua Hu ◽

Wei Qiang Gao ◽

Chao Ting Qing ◽

Cheng Sheng Fang

Keyword(s):

Real Time ◽

Calculation Method ◽

Implementation Process ◽

Cnc System ◽

Module Theory ◽

Hardware Platform ◽

Nc Code ◽

Compensation Error ◽

Algorithm Implementation ◽

Five Axis

Taking A-C axis dual rotary working table of 5-axis CNC system as an example, the function of RTCP is introduced and the performing difference between standard NC code and RTCP code is analyzed in this paper. Then, the calculation method of RTCP compensation error has been illustrated. Taking the high precision as the objective, a new real time compensation RTCP module theory is presented and its algorithm implementation process is introduced. Then, this algorithm has been simulated using MATLAB and validated in hardware platform.

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Real-Time Collision Avoidance for Five-Axis CNC Machine Tool Based on Cyber-Physical System

2018 IEEE International Conference on Advanced Manufacturing (ICAM) ◽

10.1109/amcon.2018.8615042 ◽

2018 ◽

Cited By ~ 1

Author(s):

Wen-Yang Chang ◽

Bo-Yao Hsu ◽

Jia-Wei Hsu

Keyword(s):

Machine Tool ◽

Real Time ◽

Collision Avoidance ◽

Physical System ◽

Cyber Physical System ◽

Cnc Machine Tool ◽

Cnc Machine ◽

Five Axis

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Five-axis NURBS Path Real-time Generation Method in CNC System

International Journal of Advancements in Computing Technology ◽

10.4156/ijact.vol2.issue3.6 ◽

2010 ◽

Vol 2 (3) ◽

pp. 64-69

Author(s):

Chen Liangji ◽

Gao Changyin ◽

Feng Xianzhang

Keyword(s):

Real Time ◽

Cnc System ◽

Five Axis

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Real-Time Five-Axis Control Based on Digital Copy Milling Concept to Achieve Autonomous Milling

International Journal of Automation Technology ◽

10.20965/ijat.2008.p0418 ◽

2008 ◽

Vol 2 (6) ◽

pp. 418-424 ◽

Cited By ~ 4

Author(s):

Keiichi Shirase ◽

◽

Keiichi Nakamoto ◽

Eiji Arai ◽

Toshimichi Moriwaki ◽

...

Keyword(s):

Real Time ◽

Movement Control ◽

3D Models ◽

Milling Process ◽

Numerical Control ◽

Feed Speed ◽

Tool Paths ◽

Digital Copy ◽

Copy Milling ◽

Five Axis

The Digital Copy Milling (DCM) was proposed to achieve autonomous milling, in which tool paths are generated in real time during milling without requiring Numerical Control (NC) programs. In the DCM, a tracing probe and a master model in conventional copy milling are represented by virtual 3D models, and cutter locations are calculated dynamically based on virtual tracing probe movement in real time. Therefore, not only feed speed, but also radial and axial depths of cut are adapted for milling process control. In addition, new tool paths are added to automatically avoid and recover from cutting troubles. In this paper, an added five-axis tool movement control of DCM demonstrated the effectiveness of the DCM concept.

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