Geometric Reasoning on Molding Planning for Multishot Mold Design

2006 ◽  
Vol 6 (3) ◽  
pp. 241-251 ◽  
Author(s):  
Zhou-Ping Yin ◽  
Han Ding ◽  
You-Lun Xiong
Keyword(s):  
Design Method ◽  
Automated Design ◽  
Geometric Reasoning ◽  
Geometric Constraints ◽  
Assembly Planning ◽  
Material Objects ◽  
Mold Design ◽  
Assembly Model ◽  
Contact Graph ◽  
Planning Approach

This paper presents algorithms for automated design of multishot molds for manufacturing multimaterial or multicolor objects, and focuses on molding planning that determines a sequence of mold stages required to produce the desired object. By modeling a multimaterial object as an assembly of homogenous components, a geometric reasoning approach is proposed to generate feasible or practical mold stage sequences by combining the assembly planning approach and the two-plate mold design method. First, a graph-based assembly model, namely the attributed contact graph, is derived from the B-rep models of the constituent components of the gross object by detecting and representing all the contacts between mating components explicitly. Then, all feasible mold stage sequences, represented by an AND/OR graph, are generated by reasoning on geometric constraints due to the demoldability and connectedness requirements using an assembly-by-disassembly strategy. Depending on its demoldability, each component is to be made by one of the three basic molding strategies with varied mold stages and/or mold pieces. To narrow the choice, an optimal or practical molding plan is searched from the feasible molding plans according to some criteria such as the number of mold stages, the number of side cores, and flatness of the parting line. Finally, starting from the last mold stage, mold pieces for each mold stage of the selected molding plan are constructed recursively. The feasibility of the proposed algorithms is demonstrated through an implemented prototypical system, which has been tested successfully with various multi-material objects.

A Step Towards Automated Design of Rotary-Platen Multi-Shot Molds

2003 ◽  
Author(s):  
Xuejun Li ◽  
Satyandra K. Gupta
Keyword(s):  
Lead Time ◽  
Automated Design ◽  
Basic Type ◽  
Precedence Constraints ◽  
Geometric Constraints ◽  
Material Object ◽  
Material Objects ◽  
Single Material ◽  
Improved Algorithm

This paper describes an improved algorithm for automated design of rotary-platen type of multi-shot molds for manufacturing multi-material objects. The algorithm described in this paper accounts for geometric constraints resulting from the rotary-platen process and it can handle significantly more complex interfaces. Our algorithm works in the following manner. First, we classify the multi-material object into several basic types based on the relationships among different single material components in the object. For every basic type, we find a manufacturing sequence based on the precedence constraints resulting due to accessibility and disassembly requirements. Then, starting from the last mold stage, we generate the mold pieces for every mold stage based on the manufacturing sequence. We expect that the algorithm described in this paper will provide the necessary foundations for automating the design of rotary-platen molds and therefore will help in significantly reducing the mold manufacturing lead-time associated with these types of molds.

Geometric Reasoning Based on Graph Grammar Parsing

1994 ◽  
Vol 116 (3) ◽  
pp. 763-769 ◽  
Author(s):  
Z. Fu ◽  
A. de Pennington
Keyword(s):  
Intelligent Design ◽  
Feature Recognition ◽  
Geometric Reasoning ◽  
Geometric Constraints ◽  
Graph Grammar ◽  
Feature Interaction ◽  
Knowledge Based ◽  
Feature Based ◽  
Feature Information ◽  
And Performance

It has been recognized that future intelligent design support environments need to reason about the geometry of products and to evaluate product functionality and performance against given constraints. A first step towards this goal is to provide a more robust information model which directly relates to design functionality or manufacturing characteristics, on which reasoning can be carried out. This has motivated research on feature-based modelling and reasoning. In this paper, an approach is presented to geometric reasoning based on graph grammar parsing. Our approach is presented to geometric reasoning based on graph grammar parsing. Our work combines methodologies from both design by features and feature recognition. A graph grammar is used to represent and manipulate features and geometric constraints. Geometric constraints are used within symbolical definitions of features constraints. Geometric constraints are used within symbolical definitions of features and also to define relative position and orientation of features. The graph grammar parsing is incorporated with knowledge-based inference to derive feature information and propagate constraints. This approach can be used for the transformation of feature information and to deal with feature interaction.

The Study on Mold Design System in Mechanical Engineering

2013 ◽  
Vol 644 ◽  
pp. 374-377
Author(s):  
Xue Peng Liu ◽  
Dong Mei Zhao
Keyword(s):  
Computer Aided Design ◽  
Mechanical Engineering ◽  
Design Method ◽  
Design Tool ◽  
Design System ◽  
Mold Design ◽  
Management Tools ◽  
Client Server ◽  
Standard Part Library ◽  
Aided Design

By investigating the characteristics of mold design in mechanical engineering, a framework of computer aided design tool is designed. A standard part library based on Client/Server mode and management tools are designed. The system improves the intelligence by introducing case-based design method

Towards Automated Design of Multi-Piece Permanent Molds

2003 ◽  
Author(s):  
Satyandra K. Gupta ◽  
Alok K. Priyadarshi
Keyword(s):  
Automated Design ◽  
Geometric Algorithms ◽  
Mold Design ◽  
Software System ◽  
Design Algorithm ◽  
Accessibility Analysis ◽  
Ideal Candidate ◽  
Complex Parts ◽  
Design Steps

Multi-Piece molds, which consist of more than two mold pieces, are capable of producing very complex parts—parts that cannot be produced by the traditional molds. The tooling cost is also low for multi-piece molds, which makes it an ideal candidate for pre-production prototyping and bridge tooling. However, designing multi-piece molds is a time-consuming task. This paper describes geometric algorithms for automated design of multi-piece molds. A Multi-Piece Mold Design Algorithm (MPMDA) has been developed to automate several important mold-design steps: finding parting directions, locating parting lines, creating parting surfaces, and constructing mold pieces. MPMDA constructs mold pieces based on global accessibility analysis results of the part and therefore guarantees the disassembly of the mold pieces. A software system has also been developed and successfully tested on several complex industrial parts.

Overview of Intelligent Design on Mold

2012 ◽  
Vol 459 ◽  
pp. 394-397
Author(s):  
Bin Wang ◽  
Jian Jun Chen ◽  
Jie Tao
Keyword(s):  
Artificial Intelligence ◽  
Intelligent Design ◽  
Knowledge Engineering ◽  
Design Method ◽  
Mold Design ◽  
Engineering Technology ◽  
Knowledge Based ◽  
Knowledge Reasoning ◽  
Artificial Intelligence Technology ◽  
Development Tendency

Applying Artificial Intelligence technology on mold design can help realize the design automation of mold. Because knowledge-based engineering is an effective intelligent design method, the paper systematically introduced the application and development of knowledge representation, knowledge reasoning, knowledge acquisition and other key technologies of knowledge engineering technology used in mold design field. Finally, the development tendency of mold design based on artificial intelligence was analyzed in detail

Design and Manufacturing of Air Conditioner Panel Hot Runner Injection Mold Based on CAD/CAE/CAM

2010 ◽  
Vol 42 ◽  
pp. 68-72 ◽  
Author(s):  
Zhi Gang Jin ◽  
Wu Ji Jiang ◽  
Min Xia Yu
Keyword(s):  
Design Method ◽  
Mold Design ◽  
Injection Mold ◽  
Air Conditioner ◽  
Whole Process ◽  
Injection Process ◽  
Nc Programming ◽  
Machine Module ◽  
The Cost ◽  
Design And Manufacture

Take air conditioner panel for example, it is introduced that the whole process of hot runner injection mold design and manufacture based on CAD/CAE/CAM technology. The panel structure and injection process were analyzed using HuaSu CAE software, then the panel structure was designed using UG/Mold Wizard software, the NC programming and manufacture simulating of the formed parts were done by UG/MACHINE module at last. Compared with the traditional mold design method, CAD/CAE/CAM technology not only can improve the efficiency, shorten production period, but also can reduce the cost of mold design and manufacture greatly.

scholarly journals Analysis of Geometric Obstacles Avoidance in Assembling Complex Products as a Decision-making Problem

2018 ◽  
pp. 17-34
Author(s):  
A. N. Bozhko
Keyword(s):  
Obstacle Avoidance ◽  
Information Technologies ◽  
Computational Experiment ◽  
Ordered Set ◽  
Geometric Constraints ◽  
Assembly Planning ◽  
Ordered Sets ◽  
Complex Products ◽  
Minimum Number ◽  
Person Game

Computer aided assembly planning (CAAP) of complex products is an important and urgent problem of state-of-the-art information technologies. A configuration of the technical system imposes fundamental restrictions on the design solutions of the assembly process. The CAAP studies offer various methods for modelling geometric constraints. The most accurate results are obtained from the studies of geometric obstacles, which prohibit the part movement to the appropriate position in the product, by the collision analysis methods. An assembly of complex technical systems by this approach requires very high computational costs, since the analysis should be performed for each part and in several directions.The article describes a method for minimizing the number of direct checks for geometric obstacle avoidance. Introduces a concept of the geometric situation to formalize such fragments of a structure, which require checking for geometric obstacle avoidance. Formulates two statements about geometric heredity during the assembly. Poses the task of minimizing the number of direct checks as a non-antagonistic two-person game on two-colour painting of an ordered set. Presents the main decision criteria under uncertainty. To determine the best criterion, a computational experiment was carried out on painting the ordered sets with radically different structural properties. All the connected ordered sets are divided into 13 subclasses, each of which includes structurally similar instances. To implement the experiment, a special program has been developed that creates a random ordered set in the selected subclass, implements a game session on its coloration, and also collects and processes statistical data on a group of the homogeneous experiments.The computational experiment has shown that in all subclasses of the partial orders, the Hurwitz criterion with a confidence coefficient of 2/3 and that of Bayes-Laplace demonstrate the best results. The Wald and Savage criteria have demonstrated the worst results. In the experiment, a difference between the best and worst results reached 70%. With increasing height (maximum number of levels) of an ordered set, this difference tends to grow rapidly. In the subclass of pseudo-chains, all criteria showed approximately equal results.The game model of geometric obstacles avoidance allows formalizing data on geometric heredity and obtaining data on the composition and the minimum number of configurations, the test of which objectifies all existing-in-the-product geometric constraints on the movements of parts during assembly.

scholarly journals Multi-objective aerodynamic optimization of flying-wing configuration based on adjoint method

2021 ◽  
Vol 39 (4) ◽  
pp. 753-760
Author(s):  
Xiaodong Liu ◽  
Peiliang Zhang ◽  
Guanghong He ◽  
Yongen Wang ◽  
Xudong Yang
Keyword(s):  
Optimization Design ◽  
Adjoint Method ◽  
Stokes Equations ◽  
Design Method ◽  
Adjoint Equation ◽  
Geometric Constraints ◽  
Navier Stokes ◽  
Aerodynamic Design ◽  
Aerodynamic Optimization ◽  
Multi Objective

In order to solve the multi-objective multi-constraint design in aerodynamic design of flying wing, the aerodynamic optimization design based on the adjoint method is studied. In terms of the principle of the adjoint equation, the boundary conditions and the gradient equations are derived. The Navier-Stokes equations and adjoint aerodynamic optimization design method are adopted, the optimization design of the transonic drag reduction for the two different aspect ratio of the flying wing configurations is carried out. The results of the optimization design are as follows: Under the condition of satisfying the aerodynamic and geometric constraints, the transonic shock resistance of the flying wing is weakened to a great extent, which proves that the developed method has high optimization efficiency and good optimization effect in the multi-objective multi-constraint aerodynamic design of the flying wing.

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