标签: cad

CAD质量检查器 安宝特3D Evolution质量检查器可基于多种规则对CAD图形质量进行检测，是 唯一通过SASIG和VDA规范认证的转换工具 。 它可以 自动 且准确地 识别、检查 模型中存在的错误，并提供特定 自动修复和交互式清理 功能，可以对模型质量进行批量检查和处理，大幅提升工作效率。 01 VDA 和 SASIG 质量检查 3D Evolution©质量检查器是 唯一通过 SASIG/PDQ 和 VDA 4955/2 规范认证的转换工具 ，可验证几乎所有CAD 格式的3D几何图形。 它可以 自动且准确 地将面、曲面、曲线和拓扑上的错误显示在模型上，使用者也可以在检查器树状结构中的错误类型列表中系统地选择几何图形和清除错误。 3D Evolution还具有 特定自动修复和交互式清理 功能，可用于VDA检查相关错误，例如扭曲面、迷你面等。 根据应用或客户要求，3D Evolution还可以 保存包含相关测试标准的测试配置文件 。其结果文件符合 SASIG/PDQ 和 VDA 4955/2 规范，并可以保存为 HTML 格式。 与所有其它功能模块类似，3D Evolution©质量检查器可以应用于单个部件或组件，也可以以 批量处理模式 运行。 02 LOTAR GVP 验证 该工具是与 航空航天行业 密切合作开发的，用于验证 长期存档和检索 (LOTAR) 的 CAD 数据 。 3D Evolution可以读取并验证CAD系统软件生成3D模型时，写入到STEP AP 242文件的 几何验证属性（GVP）数值 。属性值与计算值如在给定的公差范围内出现偏差，软件将自动显示这一问题。以下是GVP的示例：• 几何，例如体积、表面、质心和 COPS • 装配，例如，子级数量和实心质心 • PMI，例如折线曲线长度比较 • 曲面细分，例如质心和表面积 • 复合材料，例如，序列和切片的数量此外，软件会创建一个 满足所有 LOTAR 要求的日志文件 。当然，这一过程也可以批量执行。 03 JT数据检查 JT格式为描述结构和几何图形以及镶嵌信息提供了许多不同的可能性。要 检查应用程序创建的JT文件是否符合特定标准 ，JT检查器是一个简单的解决方案。通过 用户自定义的配置文件 ，JT检查器可以 一键检查所有相关的标准 ，例如： • XT 或 NURBS B-REP 的几何 • LOD 标准 • PLMXML 装配路径 • 单位、元数据和名字等属在检查名字标识符之后，它还可以 自动更正特定模型的名字 。通过用户定义的配置文件，可以很容易地验证数据是否获得批准，例如，与戴姆勒的JT数据交换。 此外，基于几何验证属性（GVP）的检查，例如STEP AP 242，也可用于JT格式。 04 特征和链接检查 为了审查模型的质量（如CATIA V5、NX、SOLIDWORKS和Creo等格式），该工具提供了 检查特征参数或链接连贯性 的最小值和最大值的功能，例如，检查3D模型和图纸之间的链接是否可用。如果检查到有不存在模型的错误链接，还可以检查装配结构。 关于我们 安宝特专注CAD软件，旗下产品能够有效提高CAD工程数据的互用性，轻松实现格式无损转化，集几何简化、有限元工具、高级分析等强大功能于一体。 安宝特致力于用科技，共创CAD高效协同新纪元！

产品导览： 安宝特3D Evolution具有强大的3D CAD模型转换功能，可在保留模型特征参数、注释、约束的前提下，完成不同格式3D CAD模型的无损转换 保留完整功能的CAD转换 3D Evolution©Feature Based是一款 基于特征进行格式转换 的插件，能够帮助我们可以实现3D CAD模型在不同格式之间的智能转换 它 支持24种主流3D CAD格式 ，包括CATIA V5 & V6、NX、Creo、SOLID WORKS、Inventor等等 本地阅读器可以在不访问原模型系统许可证或API的情况下，直接从二进制文件中提取模型的完整历史、特征和参数信息以及 B-REP 它能够 完整地保留草图、约束和注释的特征，包括3D PMI和元数据。 为了更好地适应目标CAD系统，3D Evolution还可以对模型的历史进行自适应优化，完成对所有参数、特征的自动重置 正因如此，3D Evolution可以实现 装配和零件的模型历史树、特征、参数的无损转化 ，是进行格式转换的不二之选 可靠性检验 为了检验转换的完整性，软件的对比功能还将 对转换前后的两个模型进行比较 当检测到差异时，日志文件会将最大的偏差列出，并 创建一个CT或3D PDF格式的轻量级可视化模型来凸显差异 草图约束 在使用3D Evolution进行转换后，具有如拉伸、填充、放样等特征的草图，还会 保有设计师在原系统中创建的约束和注释 这就使我们更容易理解并延续初始的设计意图，更好地进行模型设计与优化！

Recently, I reviewed a new electronic CAD package named Upverter for a Canadian magazine. This product is a paradigm shift away from classical CAD packages in that it is entirely web-based. There are no upfront costs or annual maintenance charges -- just a simple monthly fee. Several other aspects also differentiated it from the pack. The thing that struck me most about this product was that it allowed for multiple people to work on the same design simultaneously.   My first impression was overwhelmingly negative. "A solution looking for a problem," I thought. Without any partitioning in the design and definition of responsibilities, it would be a study in insanity. And surely I would hate to have someone looking over my shoulder, especially if he or she could "mouse out" at any time and change what I had done. Just maybe I could see this in an educational environment if the two (or more) persons were not in the same room, provided they had a back channel for communications, like an audio link (am I showing my age?) or a chat forum. In fact, I could almost see that approach being stretched into a design review.     I was discussing joint editing in general with my son and a couple of his friends, all in their early 30s. They roundly criticized my negative viewpoint. Not only did they think joint editing was a good idea, but they also described two other products that allowed the same thing and which they were using in just that way. One was a rival to PowerPoint called Prezi ; the other was Google Docs .   I was also presented with an alternate view from an endorsement on Upverter's website:   The collaborative work environment that Upverter offers has been very useful as we're often not in the same location but need to discuss technical issues with each other. With Upverter, we can not only see what the issue being described is, but help to implement a solution by selecting parts and building layouts remotely.   Still, the thought of joint design seems foreign to me. I should add that one of the issues I have with Upverter is that the whole design is always contained on a single sheet. (In fact, "sheet" is not a concept it recognizes.) Two designers could be working on different aspects of the same design simultaneously. Provided you accept that there is only one sheet, then perhaps the design of the interface of the two aspects could benefit from the interactive design.   How about you? Do you think you could start working on a design, place one symbol followed by a second, wire them together, and then have someone erase that connection and reconnect things differently? I would prefer doing this sitting next to my collaborator, but with more than two people, separate computers would certainly make this more comfortable. Can you see any advantage to this, or will the result be a compromise designed by a committee? Will this result in a faster development process, or will each change followed by some discussion slow everything down to a crawl?   I'm just "brain-stem-storming" here, but would you consider this approach for a senior designer and several junior ones as a means of helping the juniors learn their craft? Would it speed up the process, or would it simply tie the senior engineer up, preventing him or her from performing more productive things? What if the senior engineer were a lecturer, and this exercise were part of a class?   What about if two engineers were more or less of the same standing? How would they interrelate? I am pretty sure that I would become very irritated and simply withdraw. (I am not a confrontational individual.)   I find it hard to believe that this type of environment could be more productive than a single designer in any possible scenario. Nevertheless, it may be that this is the wave of the future, and I am a dinosaur, soon to be extinct if I can't adapt. Have you ever used a collaborative approach to design anything? If so, how successful was it? As always, I welcome any comments and questions.   Aubrey Kagan Engineering Manager Emphatec

I recently wrote a review for a new electronic CAD package named Upverter for a Canadian magazine. This product is a paradigm shift away from classical CAD packages in that it is entirely web-based. There are no upfront costs or annual maintenance charges -- just a simple monthly fee. Several other aspects also differentiated it from the pack. The thing that struck me most about this product was that it allowed for multiple people to work on the same design simultaneously.   My first impression was overwhelmingly negative. "A solution looking for a problem," I thought. Without any partitioning in the design and definition of responsibilities, it would be a study in insanity. And surely I would hate to have someone looking over my shoulder, especially if he or she could "mouse out" at any time and change what I had done. Just maybe I could see this in an educational environment if the two (or more) persons were not in the same room, provided they had a back channel for communications, like an audio link (am I showing my age?) or a chat forum. In fact, I could almost see that approach being stretched into a design review.     I was discussing joint editing in general with my son and a couple of his friends, all in their early 30s. They roundly criticized my negative viewpoint. Not only did they think joint editing was a good idea, but they also described two other products that allowed the same thing and which they were using in just that way. One was a rival to PowerPoint called Prezi ; the other was Google Docs .   I was also presented with an alternate view from an endorsement on Upverter's website:   The collaborative work environment that Upverter offers has been very useful as we're often not in the same location but need to discuss technical issues with each other. With Upverter, we can not only see what the issue being described is, but help to implement a solution by selecting parts and building layouts remotely.   Still, the thought of joint design seems foreign to me. I should add that one of the issues I have with Upverter is that the whole design is always contained on a single sheet. (In fact, "sheet" is not a concept it recognizes.) Two designers could be working on different aspects of the same design simultaneously. Provided you accept that there is only one sheet, then perhaps the design of the interface of the two aspects could benefit from the interactive design.   How about you? Do you think you could start working on a design, place one symbol followed by a second, wire them together, and then have someone erase that connection and reconnect things differently? I would prefer doing this sitting next to my collaborator, but with more than two people, separate computers would certainly make this more comfortable. Can you see any advantage to this, or will the result be a compromise designed by a committee? Will this result in a faster development process, or will each change followed by some discussion slow everything down to a crawl?   I'm just "brain-stem-storming" here, but would you consider this approach for a senior designer and several junior ones as a means of helping the juniors learn their craft? Would it speed up the process, or would it simply tie the senior engineer up, preventing him or her from performing more productive things? What if the senior engineer were a lecturer, and this exercise were part of a class?   What about if two engineers were more or less of the same standing? How would they interrelate? I am pretty sure that I would become very irritated and simply withdraw. (I am not a confrontational individual.)   I find it hard to believe that this type of environment could be more productive than a single designer in any possible scenario. Nevertheless, it may be that this is the wave of the future, and I am a dinosaur, soon to be extinct if I can't adapt. Have you ever used a collaborative approach to design anything? If so, how successful was it? As always, I welcome any comments and questions.   Aubrey Kagan Engineering Manager Emphatec

In the past, PCB layout designers worked from schematics that were usually drawn in a meaningful way so as to show circuit functionality and to be readable. For example, cross-page connects indicated by angled wires pointing to each other. (See My own approach to PCB symbols .)   The PCB designers made the physical parts placement follow the schematics in a logical way; components that formed functional groupings tended to remain co-located and the schematics could usually be read and understood by others -- including those who later had to use those schematics to deduce circuit operation and perform troubleshooting and repair. Re-creating a schematic from such a PCB was fairly easy.   Then along came CAD/CAE. The art of schematic drawing became debased into an electronic Etch A Sketch capture tool, whose main purpose was to create a netlist so the PCB designer could use a "rat's nest" on-screen display to complete the planting of the copper traces. Any semblance of analog rules and communication between the design engineer and the PCB layout designer was lost in the digitized dumbing-down.   All too often, the components were simply thrown at the virtual board and a multi-layer autorouter did the work. The PCB designer never even looked at the schematics and -- in many cases -- could not have understood them anyway. The resulting PCBs no longer consisted of nicely grouped functional blocks of circuitry; components ended up helter-skelter wherever they were originally (and randomly) placed. So there really was no longer any incentive -- or time in the development schedule -- for the design engineer to make the additional effort to draw readable and meaningful schematics; nobody read them anyway.   I must admit that the first time I used CAD, I was rushed ("the schedule says this has gotta be done by next week!") and my schematic was atrocious. The CAD software was not user-friendly when it came to adding additional pages once a schematic had been started. Adding more and more functions as the design progressed, I had to snake wires around the periphery of the over-crowded drawings in a way that was totally incomprehensible to anyone reading the schematic. This didn't bother me too much at first -- I knew how the thing was supposed to work and the schematic did create the netlist, which was all the PCB layout designer required.   Even then, the layout designer did not place my components where I told him to, causing the "privy too close to the well" problem discussed here on EE Times recently. But six months later, while trying to decipher a signal path from that unholy schematic, I swore that I would never draw such a useless piece of garbage ever again.   Fast forward 30 years. Much of my effort is now spent studying and analyzing PCBs from defunct OEMs for which our sales people promise our customers "We can fix anything!" Never mind that we have never seen it before, have no clue what it is supposed to do, have no backplane to slide it into, have no user manuals, have no schematics, but -- absolutely yes -- we can repair it! (Also, pigs can fly; I saw it on a TV commercial for car insurance.)   So, I have to turn these PCBs back into schematics, and then make those schematics readable so as to build test fixtures, write circuit descriptions, and clearly indicate the circuit functions for our troubleshooting technicians. And yes, I have seen many a PCB that was very obviously created by "splashing components" onto the "canvas" (much as is done by some modern art painters in a questionable state of sobriety) and clicking the auto-route button.   How can this task be accomplished effectively? Two tools I have found to be indispensible are a decent low-delta-R-indication continuity tester for unambiguously sniffing out very low-resistance PCB nets and a schematic capture package with drawing features that go far above and beyond the ability to simply create a netlist.   The schematic tool I use is freeware called TinyCAD (you can download it from SourceForge.net). While it is not perfect, it does have some very nice features that lend themselves to circuit analysis, along with basic schematic and mechanical drawing. Other drawing tools may be just as usable, but I have not studied them. The purpose of this column is to highlight the useful features of drawing software as applicable to reverse engineering. If you are aware of similar features in your own favorite drawing software, by all means comment on them below.   The first thing to realize is that a reverse engineering schematic is not intended to ever produce a netlist, so you can get away with all sorts of misdemeanors that make your drawings visually more appealing. While TinyCAD sports an extensive library of component symbols that have a very limited re-sizing option, depending on the PCB size you may prefer to construct your components as graphic objects instead of electronic components. The advantages of doing this are that the graphic objects can then be colored to represent top-side or bottom-side surface mount locations on the same drawing; also, they can be made extremely small so that the entire PCB can fit on a single drawing page.   Why a single page? Herein lies a TinyCAD weakness -- highlighting a net (more on this later) will crossover between sheets when all of the sheets are in the same drawing set, but only one sheet of this set can be made visible at any particular time. Bummer. This makes it hard to see all nodes of a net on-screen at a glance. To view more than one sheet at a time, one can open a second iteration of TinyCAD to show another sheet, but -- in this case -- highlighting a net will not crossover between sheets. Making component graphics small enough to get the whole PCB on a single sheet makes net highlighting visible across the whole page.   The result is a horrendously complex and un-readable schematic when printed onto paper. But this is NOT the schematic that will be viewed by anyone other than the reverse engineer. Its only purpose is to transform a physical PCB layout into an on-screen drawing that captures the physical layout. The functionality schematics come later after the physical schematic nets have been deciphered and re-drawn to show meaningful functionally.   The grid can be set to whatever size the user wants, but I have found that too small a grid can cause problems with block copies and moves. Best leave the grid size at "fine," and instead increase your drawing area by enlarging the page size as needed. For example, selecting a European page size A2 with font size 6 and printing at 64% scale on 11" x 17" paper gives you a single page drawing that is still readable, if you are getting on in years, a magnifying head visor helps. Printing the same at 129% gives you four 11" x 17" pages that can be taped together to give you a readable print copy. But most reading will be done on-screen, and the zoom and pan functions are very easy using the mouse scroll wheel and right-click-drag, respectively.   Another tip to work around a TinyCAD weakness is to keep "Junction Dot Placement" set to automatic. While an option for manual placement can be used, block moves afterwards cause wires to "bend" and you will have to go in and straighten them all out again.   Reverse analysis is a two-pass effort requiring an initial physical schematic based on actual PCB placement and package pinouts. This is followed by a series of functional schematics that re-draw the captured circuits in a logical and comprehensible fashion (and also catch errors when the functions appear to make no electrical sense). The physical schematic is a representation of the PCB as viewed from above.   Components are drawn in the same orientation as on the PCB; transistors are shown in their representative packages with GDS or EBC physical pins; relay switches are sown with their terminals arranged in the same way as they appear from the top; ICs are drawn in their packages with their internal logic elements or functional names shown. Many times, a PCB does not have reference designators in the silkscreen, so relating a component location to a later functional schematic depends very strongly on the physical schematic.   A physical representation can look like the image shown below. Orange is topside, green is bottomside surface mount components. Some capacitor graphics look shorted because a TinyCAD bug does not always transfer the invisible masking square when copying and pasting a selected block portion to MS Word. It would be nice if TinyCAD had a "group" function to tie graphic elements together, but one must resort to drawing a box around the graphics each time they need to be moved or copied.     Confusing, yes? It's impossible to figure out what is going on electrically from the above image. However, once this has been re-drawn into a meaningful functional schematic, the result is a very readable and understandable depiction as illustrated below:     This image is under construction. Temporarily color-coding the nets on the physical drawing make transfer to the functional drawing less prone to error. Elastic wires follow components when dragged around for readability. Unfortunately, TinyCAD does not keep wires connected when a component is rotated or flipped (mirror imaged).   When drawing the bottom-side physical component locations, it can help to first draw the area partially to scale as seen from the bottom-side, then draw a block around the circuit and flip horizontally (mirror image) to make it a topside view as seen through the PCB, and then add the topside components. Obviously there has to be some adjustment in relative positions that do not allow exact scale representation, and the connecting wires have to fit too.   You will observe in the previous drawings that individual wires can be highlighted in any color (using a standard or variable color palette) and any width. In fact, this is one of the most important features that makes TinyCAD so useful for reverse analysis.   Say you have your physical schematic drawn out on a single page, with everything scrunched up close together; long runs of closely spaced wires; impossible to make any sense of the actual electrical functions. But click on a wire and set its color to bright purple, width to 25, and apply to the entire net -- suddenly that net jumps off the page at you. Any net throughout the page with the same name attached (case critical) will also brighten into visibility.     The above drawing represents the physical layout of an entire two-PCB instrument joined by an inter-board connector. Naming nets on both sides of the connector with the same name allows highlighting that entire net in any color or line width. Later, the net connections can be re-drawn into a more representative functional schematic.   This brings us to another very useful feature in TinyCAD with regard to functional analysis. If the wire "autodrag" option is turned off and wire angle set to "free," than any wires that connect together at angles remain graphically separated from their connecting wires, even when part of the same electrical net. This means that switching functions can be depicted and the actual switch contacts can be very easily "thrown" on-screen by clicking on the wire and dragging its endpoint to a different switch contact, after which the resulting nets can be highlighted as described above.     An example of depicting switching functions on the fly is shown in the image above. This depicts a 6-pole, 6-position mechanical rotary switch with wiper contacts set to position "3," and all affected nets are highlighted in their own colors to show the electrical continuity in that switch position. Setting the contact wipers to a new position is just a matter of clicking on each contact wiper and moving the endpoint to the desired position.   This feature can be applied to any switching function. For example, a DG508 analog multiplexer IC as it might appear on the physical schematic with a suggestion of functionality is shown below:     But the functional representation illustrated below reflects this device's operation far more clearly as a rotary switch equivalent. Just grab the wiper end and rotate as required.     Simulations, scope plots, and notes can also be placed onto the schematic to help understand the various functions as illustrated in the examples below:     Another use of the wire highlight feature is in deciphering logic functions. While TinyCAD cannot do this automatically (it would be a nice feature in the ongoing development of future versions), when you have a bunch of gates, you can set inputs as Red=HI, Blue=LO, and mentally work through the logic graphically as illustrated below:     TinyCAD is also reasonably good when it comes to capturing mechanical sketches as illustrated below:       Another nice feature is the search function -- any text (note, component attribute, signal name) can easily be found this way. Remember "way back when" having to visually scour a paper plot for an elusive resistor? Individual nets can be given multiple names; all will show up in any highlight or text searches. Multiple nets can be given the same name; useful when highlighting a function such as a relay drive signal to its final destination through intermediate stages. This is one nice feature that can be used when a netlist is not ever going to be created -- doing such will tie all these intermediate stages together. Finally, when others need access to your drawings, you should have some form of revision control to keep track of the latest updated drawing. The easiest way to do this is to date and time stamp your drawings every time you save a version to a publically accessible corporate location such that the date/time printed in your drawing title block match the date/time (to the minute) of the file when saved on the public drive. Then there is no question as to whether a particular hard-copy is the latest rendition. CAD and CAE have certainly come a long way since I first fought with Daisy Systems Computer Aborted Engineering 30 years ago...   Glen Chenier Engineer