connection of nc/cnc manufacturing and reverse engineering.

by:INDUSTRIAL-MAN     2019-08-24
1.
Introduce quite a number of companies in Slovakia to produce components. component diagrams are the basis of component diagrams and can be manually drawn by computer technology.
Software using 3d technology is particularly convenient for the work of the constructor and the designer.
In the design phase of the new product, first create a 3D model and then analyze and simulate the production process.
After troubleshoot, complete the drawings and technical documents and generate components on their basis.
The problem occurs when the actual component exists. g.
In the form of hands-
Complex model
The shape and its geometric features are unknown.
Other production (
Exactly the same)
In this case, the components are problematic, especially in cases involving mass production.
Dimension features are essential in order to create a 3D model, draw, or generate the component itself.
Get more information about the components, process the data, E. G. g.
It becomes necessary through the computer, only on the basis that no data is needed can the drawings be prepared for the part production on the NC machine and CLdata be generated directly. 2.
Examples of problem definition and problem solving can be shown on the winding template of the motor stator winding that stems from the modeling and manufacture of parts that flow with unknown variable radius (Fig. 1)
As a real steel part exists in the company, but the radius flow and size are unknown.
It is a real component that was once produced abroad and its limited shape has gone through manual grinding to reverse
Template, but the drawing document for the resulting terrain is not available.
The average delivery time is more than 3 months. [
Figure 1 slightly]
According to the requirements of the sponsor, a 3D model of the part needs to be created in CAD/CAM systemPro/e to obtain CL data for generating c programs.
In the absence of data digitization, it is very difficult and often impossible to produce other complex shape parts based on existing raw data.
Since the scanning device allows real 3D objects to be converted into digital forms, data acquisition and digitization are realized.
The principle of most of these devices is based on scanning the surface of an object in its discrete points, and then presenting a digitized object as a large number of points in space on the computer, I. e. the so-
Called point cloud.
The scanners are different from each other, especially in the way in which the surface points of the object are scanned.
According to whether the scanning technology is contact or non-contact, the scanning equipment can be dividedcontact one.
The former involves 3d scanners and CMM, a static coordinate measurement system (
Control measuring instrument).
The category offers digital devices from 3D desktop devices to systems used to measure large objects a few meters in size.
The latter, non
Contact system for measurement, I. e.
Scanner, usually operated by laser or optical principle.
To a large extent, the choice of scanner types depends on the requirements for uniformity accuracy between real and digital models.
Also, another important factor when selecting ascanner is the scan time.
The fastest scanner is the laser scanner.
In addition, an important factor is the size of the scanning component, or the mobility of the scanning device.
Most scanners are limited by scanning space and can be scanned in scanning space.
3D scanners can usually scan objects of the size of 50 cm.
For larger-sized objects, larger scanning devices will be produced and then the cost will be higher. (Hrabovsky, 2002)2.
1 NC program as the output of the digital model created in the CAD/cam system, in addition to the hardware device, the software device plays an important role in the digitization of 3d objects.
A single scanning device uses its own software to process the scanned data, however the data needs to be converted several times and eventually into a neutral format (IGES, STEP,. . . )
A CAD/CAM system that can be operated.
What makes CNC so flexible and efficient is the ability to run different and difficult workpiece programs.
With the right program, processing is a button thing.
All CNC machines need to start automatic machining of new different programs if there are suitable tools and fixtures.
The creation of this new difficult project takes various approaches.
Many CNC machines can be programmed in the workshop and the operator can input data on the control panel.
This method has become very popular, especially for simple artifacts.
The program can also be \"closed\"
Line, \"stay away from the machine tool, use the computer-
Auxiliary manufacturing (CAM)software.
This method is usually used for more complex artifacts.
Latest CAM software for PC (
PC)
Many automation features are provided, making NCprogramming a driving force to a large extent.
No matter how simple or complex the workpiece is, the button is OK.
When the application becomes more complex, especially when new programs need to be written on a regular basis, it becomes more difficult to write the program manually.
The CAM system can be used to simplify the programming process.
It is a software program running on a computer (commonly a PC)
This helps CNC programmers/mechanics/manufacturing engineers to program from drawings and throughout the programming process.
The production of drawings and the programming of drawing parts are (and still is)
It\'s time consuming and there are many human errors.
Someone came up with a good idea to eliminate the diseaseand-
From the beginning of the drawing, an integrated CAD/CAM was born.
Integrated Computer
Computer-aided design
Auxiliary manufacturing (CAD/CAM)
The system produces faster and more efficient manufacturing processes.
This compatibility of the CAD/CAM system eliminates the need to redefine the configuration of the CAM system artifacts.
Most computer numerical control (CNC)
The machine is programmed using the ISO 6983 \"G and M code\" language.
Programs are usually generated by computers-
Auxiliary manufacturing (CAM)
A computer-aided design system (CAD)information.
However, ISO 6983 limits the portability of the program for three reasons: * First, the language focuses on programming the path of the tool center relative to the machine tool, rather than the machining process relative to the part.
* Second, the standard defines the syntax of the program statement, but in most cases the semantics are vague.
* Third, suppliers usually supplement the language with extensions that are not covered in the limited scope of ISO 6983. Fig.
2 shows how design data is communicated to the manufacturing department in current practice.
Design creates the specifications of the product as a 3d model.
Details determine the manufacturing requirements of the product by drawing drawings.
Path planning generates tool paths.
Production control.
The design work is to use CAD (
Computer-aided design
In the system, use the drawing CADD (
Computer-aided drawing)
In the system, the job of path planning is to use CAM (
Computer-aided manufacturing
System, control manufacturing operation using CNC system.
In many cases, CAD, CADD, and CAM functions are combined into an integrated CAD/CAM system, but in all cases the CNC functions are performed by a separate system. [
Figure 2:
Data flow in Mechanical Engineering: * First, import the information about the product into CAMsystem.
3D CAD models are usually imported.
* In mechanical engineering, CAM is used to calculate the tool path of the cutting material.
The CNC programmer only specifies the machining operation, and the CAM system creates the toolpath, usually written with CL data (
Tool location data)file.
* Import the calculated toolpath into the post-processor, and the post-processor converts the CL data to the NC program--
Specific machine code required to operate a CNC machine tool.
Different machine tools have different machine tools.
The output of the post processor should be available in the controller without further modification.
* NC program written with a symbol named G-
The code is exported to the machine and the manufacturing process can begin.
One of the most important links in the NC machining process is post-processing.
The company can have the best programming systems, the best dnc systems, and the most accurate machines, but if there is no post-processing program that can be relied upon, it is possible for the code to reach its machine to cause problems.
Most machines need to make some adjustments to the post processor so that it can generate code according to user preferences and programming habits.
Most CAMsoftware has a back processor built into it;
But there is a separate post-processing for manystands.
It is the last software link between the ideal CAD model and the \"real\" machined part.
Some questions about the post-processing subject are :(Monkova et al. , 2007)
* In CAD/CAM systems, there is no ready-made post processor for a specific \"machine/machine control\" combination, and so far the cost of developing new post processors is too high.
* In general, it is very difficult to modify the post-processing programs available in the CAD/CAM system to a specific \"machine/machine tool control\" combination, and it is often impossible.
In general, the technician must permanently correct the wrong NC program file with a text processor.
* The general post-processor for most CAD/cam systems is often difficult to adapt to 70-80years.
* For the same NC device, a separate post-processing procedure is required for each new CAD/CAM system, so the company has to pay twice for samestuff.
* Creating a custom post processor for each unique machine is often difficult and expensive.
How to simplify data flow and data transfer in manufacturing, one of the methods is to introduce step nc into production.
The concept of using step nc is simple.
It enables the product model database to be used as a direct input for CNC machine tools.
There is no separate file for the tool path.
There is no G or M code.
No post processor.
This is a completely different method of CNC programming.
Step nc is an extension of STEP, which is the standard for data exchange of product models.
STEP is an international standard for specifying a neutral data format for the digital information of the product.
STEP allows this data to be exchanged and exchanged between different and incompatible computer platforms.
Step nc specifications how to add information about CNC machining to the parts represented in the STEP product model.
Step nc defines the CNC part program as a series of operations for removing materials defined by features.
The supported features include holes, slots, pockets and volumes defined by 3D surfaces.
Each operation promotes the manufacture of features by defining the volume of materials to be removed, tolerances, the type of tool required, and some basic features (such as whether this is a rough or finishing operation.
These operations are then sorted into a work plan that converts inventory to final parts.
The work plan may be complex, including conditional operations that depend on the results of the probe operation, and can be divided into sub-
It is planned to be executed simultaneously on a machine with multiple cutting heads.
In the new method, enterprises can continue to use their existing CAD, CADD and CAM systems, but the final result is sent to CNC as a step nc AP
238 file instead of RS274D file. Fig.
3 shows the modified data stream using step nc. (ISO/DIS 14649-1, 2002)[
Figure 3 slightly]
Step nc allows a complete database of processing information around the digital product model and ultimately makes this enhanced product model possible for machine tool input.
The structure of this database makes the part feature link to a specific \"work step\" general description of various machining operations.
Step nc\'s working steps are roughly the same as the processing commands in traditional M and G code formats.
With the concept of \"work steps\" in place, the manufacturing process becomes more simplified.
Now the machine tool can receive files with step nc data, \"know\" what this means, and continue milling the workpiece without any instructions.
Machine tools will no longer be programmed for each individual workpiece.
In addition, the benefits of the standard are further expanded.
With a standard set of \"work steps\", all manufacturers will be able to share information reliably and instantly.
CAD files for step nc conversion completed on the east coast can be sent over the Internet to a machine store on the west coast, where they can start milling parts immediately.
Machine tool with PC
A control system based on an open architecture may be able to install this software to upgrade to step nc compatibility more effectively.
General input/output (I/O)
The structure and servo system of CNC machine tools do not need to be modified under stepping numerical control.
The project developing step nc estimates that the time required for CNC programming can be reduced by about 35%, reducing the number of drawings that must be sent from design to manufacturing by about 75%, and reduce the time required to process parts on CNC tools by about 50%sized job lots. (ISO/DIS 14649-1, 2002)
On the basis listed above, it can be seen that the manufacture of parts with complex shapes through CNC machines helps to create 3D models for CL data generation. 2.
2 Motor Stator winding template how to obtain a pattern of size and conditions in the College of manufacturing technology of the University of Science and Technology, seat in Presov, is to use 3D laser scanner with Dr
PICZA3 software.
Scanners with integrated hardware/software systems are the ideal 3d capture solution for all popular CAD/CAM and animation applications.
It allows designers to capture complex data for manual
Run consumer products, blister packaging designs, hand-carved characters for feature animations, and facial models for anaplatics.
It makes it very fast and easy to generate accurate 3D models, which will save the designer of the manual reverse engineering work.
It uses advanced non-
Contact laser sensors that quickly generate accurate models.
The LPX 250, combined with precision laser optics and motion control within a rigid housing, can produce high-quality scans with minimal surface noise.
The final version of the 3D model without geometric and Graphical definitions is in the drawing. 4. [
Figure 4 slightly]
The created 3D model is compared by geometry to the scanned shape.
The spacing between the measurement points is 1mm and the tolerance is 0. 1 mm.
It can be said that 98% of the surface is within the tolerance range.
Based on the establishment of the 3D model, a new solid part is made by rapid prototyping.
Through the 3D measuring device, the cast plastic parts are compared with the original real parts and then used in the real environment. (
Dorbransky & Mihalcova, 2008).
It is possible to claim that the model corresponds to the realsteel part with the required accuracy, thus generating CL data.
The obtained data was converted and applied as a NC program of the company\'s concrete CNC machine tool controller.
After creating 3D models and generating NC programs, the terms of delivery are reduced by about 98% (
From 2-180 days5 days)
Compared with the original foreign suppliers, the number of templates stored decreased by about 50%, and the price of parts manufactured in Slovakia decreased by about 60%. 3.
Conclusion manufacturing automation is one of the main goals today. the rapid development of information technology and the continuous application of computer-aided equipment in various fields of production make it possible.
In automation, the creation of NC programs and the complex manufacture of CNC machines are necessary for every factory that wants to successfully sell products in today\'s market.
The generation of CL data as output by CAM software enables the creation of NC programs for selected control systems very simply through post-processing programs.
Today, virtual 3D models are widely used in all production stages of mechanical engineering companies from proposal to delivery.
Their advantages are undeniable.
Through the 3d model, you can create a 2D format component map in a relatively short time, define the quality and geometric features of the real component and the entire structure, and perform various types of analysis, in order to simulate the machining process, the output defines the CLdata of the tool position and cutting conditions at the time of machining, and converts this data to the NC program of the joint control system of the selected NC (CNC)machine (Valicek etal. , 2009).
Creating 3D models also allows to predict conflict situations, not only in the processing of individual components, but also in the assembly of them into components and sub-components, thus reducing the preparation time, increase in cost and production quality.
Therefore, a modeling component can be the basis for its simple modification and subsequent production of other types of similar componentsg.
Technology within the group. DOI: 10. 2507/daaam. scibook. 2009. 85 4.
Quote Dobransky, J. & Mihalcova, J. (2008).
Measurement of dimensional accuracy of plastic products manufactured by injection molding, mechanical, friction, mechanical manufacturing technology22, serie c(2008), p. 153-
158, ISSN 12243264 Hrabovsky M. (2002).
Optical methods in experimental mechanics, record of 40 international Experimental Stress Analysis Conference held in Monkova K, Prague, Czech Republic, June 2002, Hatala, M. & Cep, R. (2007).
Step NC, VSBTU scientific working procedure related to manufacturing data flow--
Mechanical engineering part, Volume 153, no. 1, p. 135-139, ISSN1210-
0471 Valicek, J. , Hloch, S. & Kozak, D. (2009).
Suggestions for surface geometric parameters of advanced control water jet technology.
International Journal of Advanced Manufacturing Technology, Volume 1. 41, no. 3-4, p. 323-328, ISSN 0268-
International Organization for standardized 3768 * fdis_feb200_iso649--ISO/DIS 14649-
1 Industrial automation system and integration--
Physical equipment control ,(2002)
At: 2002-09-
28 This publication must be called: Monkova, K . [atarina]&Monka, P[eter](2009).
Connection of Nc/cNc manufacturing and reverse engineering, chapter 2009 of DAAAM international science book, pp. 881-888, B. Katalinic (Ed. )
Issued by ISBN978-DAAAM International3-901509-69-8, ISSN 1726-
Author\'s data: Vienna, Austria, 9687Eng. PhD. Monkova, K[atarina]; Doc. Eng. PhD. Monka, P[eter]
University of Technology, Faculty of manufacturing technology, koshice, located in prestov, Slovakia, Sturova 31,080 01, monkova.
Catalina @ apeiron.
EU, direct @ apeiron.
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