Haptic Sculpting and 5-Axis Pencil-Cut Planning in Virtual Prototyping and Manufacturing

Materials ◽  
2003 ◽  
Author(s):  
Weihang Zhu ◽  
Yuan-Shih Lee

In this paper, a Two-phase approach to tool collision detection and local gouging elimination is proposed for haptic pencil-cut of sculptured surfaces. Pencil-cut is a special kind of machining operation, whose purpose is to use relatively smaller tools to remove rest material on the corners or highly curved regions that are inaccessible by bigger tools. Tool orientation determination and tool collision avoidance are critical issues for 5-axis pencil-cut tool path planning. Detailed techniques of haptic rendering and tool interference avoidance are discussed for haptic-aided 5-axis pencil-cut tool path generation. Hardware and software implementation of the haptic pencil-cut system with practical examples are also presented in this paper.

Author(s):  
Yuan-Shin Lee ◽  
Tien-Chien Chang

Abstract In this paper, a methodology of applying convex hull property in solving the tool interference problem is presented for 5-axis NC machining of free-form surfaces. Instead of exhausted point-by-point checking for possible tool interference, a quick checking can be done by using the convex hull constructed from the control polygon of free-form surface modeling. Global tool interference in 5-axis NC machining is detected using the convex hull of the free-form surface. A correction method for removing tool interference has also been developed to generate correct tool path for 5-axis NC machining. The inter-surface tool interference can be avoided by using the developed technique.


2021 ◽  
Author(s):  
Yuanming Wang ◽  
Jixiang Yang ◽  
Dingwei Li ◽  
Han Ding

Abstract In the robotic polishing process, the tool and the blisk interfere easily because of the narrow operation space and seriously twisted curved surfaces. Algorithms are proposed to detect and avoid collisions with high efficiency and accuracy. First, the curved surface of the blade is discretized into a set of points, and the collision detection between the tool and the blisk is converted into the calculation of distances between the tool and points on blade surface. Then, the tool axial vector is adjusted with the minimum rotation angle to avoid collision, which reduces the impact on surface profile accuracy after changing the tool postures. The machining quality is finally guaranteed by con-trolling the material removal depth of the polishing process. The proposed method realizes the collision detection and interference avoidance of the blisk polishing effectively, while it also ensures the surface quality of workpiece when adjusting the tool posture. Simulation and experiments are carried out to verify the feasibility and advantages of the proposed method.


2012 ◽  
Vol 723 ◽  
pp. 130-135
Author(s):  
Li Qiang Zhang ◽  
Da Zhong Wang

Five-axis high speed machining can improve the efficiency and accuracy obviously, but the machining errors and tool interference are likely to happen due to the complexity of tool motion. So the collision detection and verification of tool path are very important and necessary before machining the part. Using a combination of process simulation and collision detection based on image analysis, a rapid detection approach is developed in this research. The geometric model provides the cut geometry for the collision detection and records a dynamic geometric information for in-process workpiece. For the precise collision detection, a strategy of image analysis method is developed in order to make the approach efficient and maintian a high detection precision. An example of five-axis machining propeller is studied to demonstrate the proposed approach.


Author(s):  
Marion W. Vance ◽  
Kyle D. Squires

An approach to parallel solution of an Eulerian-Lagrangian model of dilute gas-solid flows is presented. Using Lagrangian treatments for the dispersed phase, one of the principal computational challenges arises in models in which inter-particle interactions are taken into account. Deterministic treatment of particle-particle collisions in the present work pose the most computationally intensive aspect of the simulation. Simple searches lead to algorithms whose cost is O(N2p) where Np is the particle population. The approach developed in the current effort is based on localizing collision detection neighborhoods using a cell-index method and spatially distributing those neighborhoods for parallel solution. The method is evaluated using simulations of the gas-solid turbulent flow in a vertical channel. The instantaneous position and the velocity of any particle is obtained by solving the equation of motion for a small rigid sphere assuming that the resulting force induced by the fluid reduces to the drag contribution. Binary particle collisions without energy dissipation or inter-particle friction are considered. The carrier flow is computed using Large Eddy Simulation of the incompressible Navier-Stokes equations. The entire dispersed-phase population is partitioned via static spatial decomposition of the domain to maximize parallel efficiency. Simulations on small numbers of distributed memory processors show linear speedup in processing of the collision detection step and nearly optimal reductions in simulation time for the entire solution.


2011 ◽  
Vol 474-476 ◽  
pp. 961-966 ◽  
Author(s):  
Li Qiang Zhang ◽  
Min Yue

Collision detection is a critical problem in five-axis high speed machining. Using a combination of process simulation and collision detection based on image analysis, a rapid detection approach is developed. The geometric model provides the cut geometry for the collision detection and records a dynamic geometric information for in-process workpiece. For the precise collision detection, a strategy of image analysis method is developed in order to make the approach efficient and maintian a high detection precision. An example of five-axis machining propeller is studied to demonstrate the proposed approach. It has shown that the collision detection task can be achieved with a near real-time performance.


2010 ◽  
Vol 23 (4) ◽  
pp. 486-494 ◽  
Author(s):  
Xu Rufeng ◽  
Chen Zhitong ◽  
Chen Wuyi ◽  
Wu Xianzhen ◽  
Zhu Jianjun

Author(s):  
Zezhong C. Chen ◽  
Wei Cai

To address a major technical challenge in simulating geometric models of machined sculptured surfaces in three-axis virtual machining, this paper presents an efficient, accurate approach to representing the 3D envelopes of a cutter sweeping sequentially through cutter locations; these envelopes embody the furrow patches of the machined surfaces. In our research, the basic mechanism of removing stock material in three-axis computer numerically controlled (CNC) milling of sculptured surfaces is investigated, and, consequently, an effective model is proposed to represent the 3D envelopes (or furrow patches). Our main contribution is that a new directrix (or swept profile) of the furrow patches (mathematically, ruled surfaces) is identified as a simple 2D envelope of cutting circles and is formulated with a closed-form equation. Therefore, the 3D cutter-swept envelopes can be represented more accurately and quickly than the existing swept-volume methods. With this innovative approach, a method of accurate prediction of the machining errors along tool paths in three-axis finish machining is provided, which is then applied to the optimization of tool-path discretization in two examples. Their results demonstrate the advantages of our approach and verify that the current machining-error-prediction methods can cause gouging in three-axis sculptured surface milling.


1999 ◽  
Vol 23 (2) ◽  
pp. 275-286
Author(s):  
A. Vafaeesefat ◽  
H.A. EIMaraghy

This paper present a method to generate 3-axis NC programs for rough milling processes. A raster digitizing of the solid volume delimitated by sculptured surfaces to be machined is first created. This is accomplished by using the so-called Z-buffer created from a parallel projection of all surfaces. Conventional rendering software can be used to generate the Z-buffer. This volume is transformed into a 3-D mesh composed of “empty”, “full”, and “mixed” blocks. Machining is preformed from top to bottom in a sequence of horizontal cutting planes. At each level of planar machining, spiral routines are used to generate the tool path. The proposed method is valid for generating tool paths for general cavities bounded by arbitrary surfaces. One of the notable advantages of the proposed method is that the tool path generation is independent from the geometric description of bounding surfaces. An example is used to illustrate the approach and its advantages.


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