Image Morphology-Based Path Generation for High-Speed Pocketing

2020 ◽  
Vol 142 (4) ◽  
Author(s):  
Bingfei Xiang ◽  
Yingguang Li ◽  
Ke Xu ◽  
Mengyuan Yang
Keyword(s):  
High Speed ◽  
Geometric Constraints ◽  
Aviation Industry ◽  
Path Generation ◽  
Pocket Milling ◽  
Parallel Path ◽  
Mirror Milling ◽  
Local Modification ◽  
Initial Path ◽  
Image Morphology

Abstract Pocket milling has long been a popular means for machining pocket features in structural parts and skins in the aviation industry. Recent advanced milling technologies pose new challenges for pocket milling path which existing contour-parallel path generation schemes cannot overcome. For high-speed machining, pocket milling path is desired to be smooth and with no tool retractions during the process, while the path stepover should be kept within a prescribed range to achieve relatively constant cutting load. These geometric constraints are also vital in the application of aircraft skin mirror milling in order to guarantee a correct and consistent thickness signal reception for real-time adjustment of the process. Traditional path optimization based on local modification can only meet a few of these constraints while others are being violated. Therefore, we propose a novel contour-parallel path generation scheme that respects all these process constraints by utilizing the idea of image morphology. The two-step scheme first generates an initial path by propagating from the rectified medial curve of the pocket shape. The initial path is then treated as a binary image being iteratively deformed and projected back into the pocket region via quadratic optimization. Experimental results show that our developed scheme can generate a smooth, tool retraction free and stepover-guaranteed path for various shapes of pocket.

Novel path generation algorithm for high-speed pocket milling

2013 ◽  
Vol 52 (2) ◽  
pp. 397-404 ◽  
Author(s):  
Xiongbing Li ◽  
Jiajia Liang ◽  
Peijun Ni ◽  
Yuguo Wang ◽  
Yongfeng Song ◽  
...  
Keyword(s):  
High Speed ◽  
Path Generation ◽  
Generation Algorithm ◽  
Pocket Milling

A Study on the Deformation due to High Speed Processing of Aircraft Wing Structure

2021 ◽  
Vol 880 ◽  
pp. 63-68
Author(s):  
Jihye An ◽  
Hyunji Kim ◽  
Dohyeon Kim ◽  
Sangkyoo Nam ◽  
Yunyoong Yoo ◽  
...  
Keyword(s):  
Residual Stress ◽  
High Speed ◽  
Tensile Force ◽  
Tensile Load ◽  
Working Hours ◽  
Frictional Heat ◽  
Aviation Industry ◽  
High Speed Machining ◽  
Skilled Workers ◽  
Processing Site

Residual stresses generated during high-speed machining of spoiler beams used in aircraft cause product deformation and dimensional mismatch, which increases the defect rate and leads to material waste. To overcome this problem, the processing site uses manual modification techniques that stretch part of the workpiece according to the experience of skilled workers. However, due to the nature of the aviation parts industry, there are no established methods for modification of product shapes and parts. Studying the modification process would allow for increased productivity, such as shorter working hours, throughout the aviation industry. In this study, a method of predicting residual stress due to frictional heat generated during high-speed machining and applying a tensile force to a model deformed by residual stress was used to modify the product. Our analysis showed that a degree of deformation similar to the measured value was produced, and that the product was modified by applying a tensile load.

An Algorithm for a Near Optimal NC Path Generation in Staircase (Lase) Traversal of Convex Polygonal Surfaces

1999 ◽  
Vol 122 (1) ◽  
pp. 182-190 ◽  
Author(s):  
S. V. Kamarthi ◽  
S. T. S. Bukkapatnam ◽  
S. Hsieh
Keyword(s):  
Rapid Prototyping ◽  
Path Length ◽  
Tool Path ◽  
Path Generation ◽  
Convex Polygons ◽  
Sweep Angle ◽  
Pocket Milling ◽  
Different Shapes ◽  
Path Lengths ◽  
Better Than

This paper presents an analytical model of the tool path for staircase traversal of convex polygonal surfaces, and an algorithm—referred to as OPTPATH—developed based on the model to find the sweep angle that gives a near optimal tool path length. The OPTPATH algorithm can be used for staircase traversal with or without (i) overlaps between successive sweep passes, and (ii) rapid traversal along edge passes. This flexibility of OPTPATH renders it applicable not only to conventional operations such as face and pocket milling, but also to other processes such as robotic deburring, rapid prototyping, and robotic spray painting. The effective tool path lengths provided by OPTPATH are compared with those given by the following two algorithms: (i) a common industrial heuristic—referred to as the IH algorithm—and (ii) an algorithm proposed by Prabhu et al. (Prabhu, P. V., Gramopadhye, A. K., and Wang, H. P., 1990, Int. J. Prod. Res., 28, No. 1, pp. 101–130) referred to as PGW algorithm. This comparison is conducted using 100 randomly generated convex polygons of different shapes and a set of seven different tool diameters. It is found that OPTPATH performs better than both the IH as well as PGW algorithms. The superiority of OPTPATH over the two algorithms becomes more pronounced for large tool diameters. [S1087-1357(00)71501-2]

Tool Path Generation Method of Equal Approximation Error for Free-Form Surface in High Speed Machining

2010 ◽  
Vol 102-104 ◽  
pp. 544-549 ◽  
Author(s):  
Chun Jiang Zhou ◽  
Hong Chun Chen
Keyword(s):  
High Speed ◽  
Tool Path ◽  
Cutting Tool ◽  
End Milling ◽  
Approximation Error ◽  
Tool Path Generation ◽  
Free Form ◽  
Path Generation ◽  
High Speed Machining ◽  
Free Form Surface

The development of surface high-speed machining has put forward higher demands for uniform cutting load and smooth cutting tool path. Most current tool-path planning methods are based on constant scallop height, but they have the disadvantage of path point redundancy during the path discretization process. To overcome the problem, a tool path generation method of equal approximation error in each step for free-form surface is presented based on geodesic principle and curvature judgment. In this method, the NURBS curve is employed to realize smooth transition for adjacent two tool paths in high-speed machining. A certain angle of inclination of flat-end milling cutter during multi-axis machining improves the machining efficiency. Because of the advantage of this machining condition, the cutter location point generation algorithm during the machining condition is given by the method. The method is verified and simulated by C++. Experiment results proved that it can obtain uniform cutting load and continuous smooth cutting tool path during surface high-speed machining by the proposed method.

South-east Asian aviation faces growing pains

2019 ◽  
Keyword(s):  
High Speed ◽  
Aviation Industry ◽  
South East Asia ◽  
Kuala Lumpur ◽  
High Speed Railway ◽  
Content Type ◽  
Passenger Traffic ◽  
Development Costs ◽  
Growing Pains ◽  
The World

Subject Challenges facing South-east Asia's aviation industry. Significance South-east Asia is experiencing one of the sharpest increases in air passenger traffic anywhere in the world. Besides intensifying competition between airlines, this is prompting disputes over airspace and straining capacity at many of the region’s airports. Impacts Indonesia’s establishment of air defence identification zones could intensify territorial and airspace disputes in the South China Sea. The deferral of the Kuala Lumpur-Singapore high-speed railway will mean little change to air traffic levels between the two places. Changes to funding for Malaysian airport operators could result in higher fees being passed on to passengers to cover development costs.

HSM Strategies of CAD/CAM Systems — Part I Tool Path Generation

2010 ◽  
Vol 426-427 ◽  
pp. 520-524 ◽  
Author(s):  
Song Lin Ding ◽  
John Mo ◽  
D. Yang
Keyword(s):  
High Speed ◽  
Metal Cutting ◽  
Tool Path ◽  
Tool Path Generation ◽  
Path Generation ◽  
Cnc Machine ◽  
Technical Requirements ◽  
Cad Cam ◽  
High Feed ◽  
Cutting Processes

Owning to the ultra high feed rate and spindle speed, tool path patterns which are less important in conventional metal cutting processes becomes critical in High Speed Machining (HSM). Without an appropriate tool path strategy HSM can not be fully implemented even though the CNC machine has HSM potentials. In practice attentions are usually drawn to advanced hardware components; tool path pattern catering to HSM is often overlooked. This paper introduces the principles of tool path generation for HSM. Essential properties of HSM and its technical requirements on the CAD/CAM system are summarized. The state-of-the-art technologies and practice-oriented tool path generation methodologies are presented.

Bimaterial Micro-Structured Annulus With Zero Thermal Expansion Coefficient

2017 ◽  
Author(s):  
Yan Xie ◽  
Dengfeng Lu ◽  
Jingjun Yu
Keyword(s):  
Thermal Expansion ◽  
Thermal Expansion Coefficient ◽  
Expansion Coefficient ◽  
High Speed ◽  
Thermal Strain ◽  
Geometric Constraints ◽  
Geometrical Parameters ◽  
Thermal Behaviors ◽  
Lattice Cell ◽  
Triangular Cell

This paper mainly concentrates on the design and analysis of the annulus with zero thermal expansion coefficient (ZTE) aiming to solve the heat generation and deformation in high speed bearing. First, a fork-like lattice cell inspired by the basic triangular cell is put forward and further applied to construct an annulus. The stretch-dominated lattice cell utilizes the Poisson’s contraction effect to achieve the tailorable thermal expansion coefficient (CTE). The thermal behaviors differences between the continuous interfaces and lattice cells will lead to the internal stress. Thus, the CTE of the annulus consisting of the lattice cell can be tailored to zero even negative values through the offset between the thermal-strain and force-strain. Then a theoretical model is established with some appropriate assumptions to reveal the quantitative relations among the geometrical parameters, material properties and equivalent CTEs thoroughly. The prerequisites for realizing a zero CTE are further derived in terms of material limitations and geometric constraints. Finally, FEA method is implemented to verify and analyze the thermal behaviors of annulus. The proposed annulus design characterized by the CTE tunability, structure efficiency and continuous interfaces is hopefully to be applied in the high speed bearings, adapters between the shaft and collar and fastener screws.

Study on Planning Strategy of Harbin Aviation and Automobile Industry City

2011 ◽  
Vol 243-249 ◽  
pp. 1731-1736
Author(s):  
Xin Yue ◽  
Ting Wan
Keyword(s):  
Automobile Industry ◽  
High Speed ◽  
Economic Globalization ◽  
Current Situation ◽  
Aviation Industry ◽  
Land Utilization ◽  
Planning Strategy ◽  
Urban Function ◽  
Ecological Landscape ◽  
Planning And Construction

Under the great background of economic globalization, high-speed development of airplane and automobile industry as well as Harbin Aviation and Automobile Industry City as one of national aviation industry bases, this paper conducts a systemic study on Harbin Aviation and Automobile Industry City. Upon the basis of study on the development background as well as current situation of the industry city, regional overall planning, land utilization, urban function, ecological landscape and culture as well as other planning and development strategies of the industry are mainly discussed in this paper, and, hereby planning prospects are put forward so as to provide certain reference for the planning and construction of industry cities.

scholarly journals ОСОБЛИВОСТІ ЗАБЕЗПЕЧЕННЯ АЕРОДИНАМІЧНИХ ХАРАКТЕРИСТИК РЕГІОНАЛЬНОГО ПАСАЖИРСЬКОГО ЛІТАКА

2019 ◽  
pp. 106-133
Author(s):  
Олександр Дмитрович Донець ◽  
Володимир Олександрович Кудрявцев
Keyword(s):  
High Speed ◽  
Research Work ◽  
Flight Dynamics ◽  
Aerodynamic Characteristics ◽  
Static Stability ◽  
Control Mode ◽  
Aviation Industry ◽  
Maximum Speed ◽  
Flight Tests ◽  
Aerodynamic Configuration

Principal results of the computational and research work performed during development of a regional passenger aircraft to ensure its aerodynamic characteristics are given. When creating the An-148-100/An-158 family of aircraft, such level of the aircraft aerodynamic perfection was achieved, which ensured fulfillment of the specified requirements for their flight performance – maximum speed, cruising flight altitude and flight range with different payloads. The developed aerodynamic configuration made it possible to create a family of regional passenger high-wing planes with a flight speed of up to 870 km/h (true speed) (M = 0.8), which have no analogues in the world aviation industry. Developed for the An-148-100 / An- 158 aircraft, supercritical profiles of the new generation with a large maximum relative thickness formed the basis of the aerodynamic configuration of a high-speed  wing with moderate sweep. The aircraft lift-to-drag ratio in cruise flight is Kcruise = 15.8, which corresponds to the worldwide values. Developed aerodynamic configuration of the wing high-lift devices provides high bearing properties of the wing during take-off and landing stages, which allows to fully meet the requirements for the runway required length of the base airfields Lrun = 1485...1950 m. Developed algorithms are implemented in the electric remote control system and provide necessary standard characteristics of stability, controllability and flight dynamics in the main control mode. Selected margins of the aircraft’s own static stability and effectiveness of its controls ensure safe completion of the flight in standby control mode. The certification flight tests of the An-148-100/An-158 airplanes confirmed full compliance of their take-off and landing performance, as well as the stability, controllability and flight dynamics characteristics with the requirements of the Certification basis in both standard and in failure situations tested in flight tests. Necessary and sufficient amount of experimental work was conducted in the lowspeed  and high-speed wind tunnels of the ANTONOV SC and TsAGI to verify the aerodynamic and spin characteristics of the An-148-100/An-158 airplane models, which improved the aerodynamic configuration of the aircraft and its individual units and allowed to apply the work results in calculation of aircraft strength, as well as for development of their systems.

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