Abdullah Ahmed
Unit 17: Computer Aided Drafting Draf ting in Engineering: Engineering: Task 1
Computer Computer aided design (CAD) has several advantages over traditional traditional manual drafting techniques:
CAD enables the the modern engineer engineer to produce very accurate and elaborate designs. CAD improves the rendering quality of the surfaces, triangulation, and accuracy of lines and curves. CAD CA D tools tools allow the the ability to make two lines or shapes coincide, become beco me parallel, pa rallel, perpendicular, perpendicular, equal, or tangent. tangent. These tools greatly improve the the detail and and accuracy acc uracy of the design. It also allows the the user to organise complex designs in a way which enables enables easier presentation of information previously not possible using traditional methods. CAD also allows a llows the the user to freely rotate the the model in all directions, thereby allowing the observation of certain angles and viewpoints previously not possible using using manual manual drawing d rawing techniques. techniques. Dimensions Dimensions and coordinates coordi nates of CAD can be retrieved with the the same precision as the the original measuremen measurement. t. However, using using manual draftin dra fting g techniques measurements often have to be recalculated and redrawn. CAD files can be attached attached to various external external devices such such as 3D printers, printers, CNC and laser cutting machines, allowing the engineer to manufacture the product with ease in a comparably shorter time. CAD also allows the the user to modify and manipulate pre-existing pre-existing dimensions with relative ease; whereas if one were to change measurement measurementss in manual manual design, there is a likely possibility of redrawing the design. The use of CAD also allows the user to run the design under virtual stress conditions, and can subsequently troubleshoot or debug the design. For example SolidWorks has tools such as interference detection, detection, collision detection, detection, failure detection detection,, drop/impact testing, bucklin b uckling g or collapse prediction, heat or cooling simulation, simulation, repeated loaded simulation, simulation, flow simulation and more.
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Abdullah Ahmed
CAD systems have the ability to ‘zoom’ into the design, so the user can magnify certain features for further inspection.
The functionality of CAD programs which allow the testing of a model in virtual stressed environments is called finite element method or analysis (FEM or FEA). These systems calculate the stress, heat transformation, fluid flow, deformation, magnetic field distribution, electrostatics, and more. The functions in CAD allow users to share their files easily, as it is completely digital. Traditional manual drafting techniques required entire rooms for storage. As CAD software is digital, this negates the necessity of large rooms. Document reproduction is easier by certain features such as copy and paste. Parametric modelling is the use of various parameters to design a model. Parameters can be dimensions, coordinates, and material properties. These parameters can, if one wishes to do so, be modified at any time during the design and will automatically be updated. There is usually a relationship between each individual part of an assembly Parametric modelling is also more visually appeasing, and is especially useful when displaying the design to people who are from nonengineering backgrounds. The Final version of the product is cleaner and closer to the actual end product. The meticulous detail in parametric modelling allows one to analyse the product more realistically.
Disadvantages of CAD over traditional manual drawing techniques:
Implementing CAD systems into a company’s PLM solution can be very expensive. The use of manual drafting is much cheaper, as all that is required is relatively cheaper drawing equipment. Training employees for using CAD can also be very expensive in itself and involves a higher learning curve. When the company is in transition between manual drafting and CAD, it can often take a long time to switch to the new method.
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Abdullah Ahmed
Task 2
Below is listed some of the most popular CAD software and the operating system required to run it. The CAD software listed below, are all supported by Windows 7, or upwards. However, some of them require a 64 bit operating system rather than a 32 bit operating system. A 64 bit computer system requires a 64 bit CPU which handles more information and has a larger capacity of RAM than a 32 bit operating system. Windows So lidWorks 2015 AutoCAD 2015 Si emens NX9
Sk etchUp PRO 2014 Inve ntor 2 015 CAT IA V6
PRO/Engineer Wildfire 5.0
Windows 7, Windows 8, Windows 8.1 (64 bit only) Windows 7, Windows 8, Windows 8.1 (64 bit and 32 bit) Windows 7, Windows 8, Windows 8.1 (64 bit only)
UNIX/Linux
Mac OS X
Officially not supported*
Officially not supported*
Officially not supported*
Mac OS X V10.10.0+
Red Hat Enterprise Linux (6 and 7), SuSE Linux Enterprise Server (11 and 12) Windows Vista, Officially not Windows 7, Windows supported* 8, Windows 8.1 (64 bit and 32 bit) Windows 7, Windows Officially not 8, Windows 8.1 (64 supported* bit and 32 bit) Windows 7, Windows Red Hat Enterprise 8, Windows 8.1 (64 Linux (5.5, 6.1, 6.2), bit and 32 bit) SuSE Linux Enterprise Server 11 SP1 and SP2, Solaris 10, Solaris 11 Windows XP, Officially not Windows Vista, supported* Windows 7, Windows 8, Windows 8.1 (64 bit and 32 bit)
Mac OS X 10.7+, 10.8+, 10.9+
Mac OS X 10.7+, 10.8+, 10.9+
Officially not supported* Officially not supported*
Officially not supported*
*Although the software manufacturer does not allow the support of certain operating systems, they can still be used with a virtual machine (on Mac, Linux, or UNIX) or with ‘Wine’ (Linux only).
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Abdullah Ahmed
In modern engineering, 3D model design with CAD is vital to ensure the success of a product. Below is the comparison of two parametric modelling CAD programs produced by Dassault Systèmes: CATIA and SolidWorks. CATIA CATIA focusses on 3D modelling and prototyping as replacements for engineering drawings whereas SolidWorks provides a number of 3D and 2D tools for mechanical engineering. CATIA specialises in surface rendering operations. For example, if one were to surface an apple with a bruise it will be better to use CATIA rather than SolidWorks, therefore it is more appropriate for designing cars, aircrafts, and boats. CATIA is a high end product lifestyle management solution which focuses on the concept, design, development, and the deployment of a product. CATIA is used by large companies like Boeing, AirBus, Chrysler, Fiat, Ford, Hyundai, Peugeot, Toyota, Volkswagen, United States Navy, and more. CATIA is more suitable for larger companies.
SolidWorks SolidWorks is a much more affordable product than CATIA. While CATIA’s licensing is very expensive SolidWorks is cheaper and easier to use. SolidWorks is a much simpler version of CATIA without advanced tools that are not usually required for smaller companies. SolidWorks focusses on product development, and is more suitable for smaller companies and/or large companies who have no use of advanced tools which are available in CATIA.
Depending on the product being manufactured, the official hardware requirements for CAD vary. In the table below, the computer processing unit (CPU), the video processing unit or graphics processing unit (GPU or VPU), and the random access memory (RAM), and hard disk drive (HDD) requirements are shown. The CPU controls and coordinates the actions of the entire PC. RAM is essentially memory which provides a place for the CPU and other components to temporarily store data which the system needs to access rapidly. The GPU is a miniature computer in itself dedicated solely to processing graphic related data. The graphics card has its own GPU and its own dedicated Video RAM (VRAM). 4
Abdullah Ahmed
As described earlier, RAM is a temporary for m of storage. HDD’s, however are a magnetic storage device which act like memory, except that they are semipermanent, slower and larger in capacity. This means that data will still remain on the hard drive, even when there is no power. If a company wishes for better performance, they may use Solid State Drives (SSD) rather than HDD’s. Even though they both act like memory, SSD’s combine the advantages of the speed of RAM and the permanent nature of HDDs. Unlike a hard drive, SSD’s have no mechanical movin g parts, and are cheaper, faster and reliable. Due to the non-essential use of SSD ’s in CAD, the table below will assume that all storage memory are HDD’s. Official System Requirements SolidWorks 2015 CPU: Pentium 4, or AMD Athlon with SSE2 technology*. RA M: 8GB recommended. GPU: DirectX 9 compliant graphics card. HD D: 5GB or more. Auto CAD 2015 CPU: Pentium 4, or AMD Athlon with SSE2 technology*. RAM: 2GB (8GB recommended). GPU: DirectX 9 compliant graphics card (DirectX 10 recommended). HD D: 6GB or more. Inve ntor 2015 CPU: Pentium 4, or AMD Athlon with SSE2 technology*. (Intel Xeon or i7 equivalent recommended). RAM: 8GB (16GB recommended). GPU: DirectX 9 compliant graphics card (DirectX 10 recommended). HD D: 12GB or more. PRO/Engineer CPU: Pentium 4, or AMD Athlon with SSE2 technology*. Wildfire 5.0 RA M: 1GB or more recommended. GPU: DirectX 9 compliant graphics card. HD D: 3GB or more. *SSE2 technology (Streaming SIMD Extensions 2) is an instruction set which was introduced by Intel in 2001 in their Pentium 4 processors, and AMD Processors in 2003. At initial inspection, one may think that the hardware requirements for CAD are hefty. However, the requirements stated by the manufacturer are the recommended requirements rather than the minimum requirements. Depending on the nature of CAD usage in a company, the requirements can vary. If a 5
Abdullah Ahmed
company produces 2D engineering drawings only, then the requirements will be lower. However using 3D design, the requirements are much higher. Depending on the number of parts that are being produced during a CAD design, the requirements could vary from being a mid-spec machine to a high-spec machine. The table below shows the typical requirement ranges for CAD.
2D only
3D Below 100 3D Around parts 100-500 par ts
CPU: Intel Pentium 4 or AMD equivalent.
CPU: Intel Core 2 Duo or AMD equivalent.
CPU: Intel i5 (4th gen) or AMD equivalent
3D Around 500-1000 parts CPU: Intel i7 (4th gen) or AMD equivalent
3D Above 1000 parts
RA M: 2GB
RA M: 4GB
RA M: 8GB
RA M: 12GB
RA M: 16GB+
GPU: DirectX 9 integrated graphics card, 256 MB VRAM (Intel HD 4000 or AMD equivalent).
GPU: DirectX 10 dedicated graphics card, 512 MB VRAM (Nvidia GeForce GT 610 or AMD equivalent).
GPU: DirectX 10 dedicated workstation graphics card, 1024 MB VRAM (Nvidia Quadro K2000 or AMD equivalent).
GPU: DirectX 11 dedicated workstation graphics card, 2048 MB VRAM (Nvidia Quadro K5000 or AMD equivalent).
GPU: High end DirectX 11 dedicated graphics cards in SLI or CrossFireX*. 4096 MB VRAM (Nvidia Quadro K6000 or AMD equivalent).
HD D: Around 5-12 GB
HD D: Around 5-12 GB
HD D: Around 5-12 GB
HD D: Around 5-12 GB
HD D: Around 5-12 GB
CPU: Intel Xeon or AMD equivalent
*SLI and CrossFireX are both brand names for multi GPU solutions offered by Nvidia and AMD. These technologies use parallel processing which increases processing power available for graphics cards. A workstation is built for high performance and heavy workloads, often having multiple processors and graphics card s, while PC’s can only handle one of each. 6
Abdullah Ahmed
Workstation graphics cards such as the Nvidia Quadro and AMD FirePro are specifically designed for CAD. While not essential, a large company which is looking to make more than 500 part assemblies should consider purchasing these rather than the ordinary series of graphics cards provided by Nvidia and AMD. Other output devices such as monitors (preferably with a resolution of at least 1280x1024) mice, keyboards are required. Other hardware m ay be used, if one prefers to do so, but they are not essential in the implementation of CAD. For optimal performance, drivers should regularly be updated, especially the graphics card. As video card manufacturers are constantly finding new ways to optimise the hardware, it is recommended to update the drivers regularly.
Task 3
Once a design on a CAD program has been completed it can be manufactured using a normal printer, 3D printer, Computer numerically controlled (CNC) machine or a laser cutter. Computer-aided manufacturing (CAM) which is the use of computer software to manufacture product components can directly import data from CAD software, and can then relay information to the relevant apparatus to produce the design. However, a number of CNC machines can now directly import data from CAD software. CAM can import geometrical designs from CAD, and can then manufacture the design using a CNC machine or Direct Numerical Control (DNC) machines. Originally, Numerical control (NC) machines which used geometric data which was encoded mechanically. CAD/CAM software are both computer systems, therefore these systems are highly integrated. Therefore the software and hardware involved are generally referred to as CAD/CAM and are known as a computer integrated manufacturing (CIM) process. The use of CAD/CAM systems overcame the disadvantages of using NC machines. CAD/CAM systems are economically efficient, faster, easier to use and are easily integrated into the design and manufacturing process. The set of instructions which are passed from the CAD software to the CAM software contain geometric information about the positioning of the cutting tool, the cutting speed, and other information is also encoded. This method requires 7
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extensive knowledge of a very complex programming language, this is where CNC programmers come into the picture. Rapid prototyping is a group of techniques which is used to manufacture a part using CAD. Rapid prototyping imports geometric data from CAD software and transforms it into horizontal cross sections which are added to until the model is complete. The construction is usually accomplished through 3D printing. Laser cutting is a method of manufacturing which uses a laser to cut materials. Some CAD software can interact with certain other software which can provide a variety of optimisation techniques such as simulated annealing and genetic algorithms. These are, from the field of artificial intelligence, methods which can solve constrained problems, and can potentially help to improve parameters of a designed model. Before manufacturing the CAD designs, the appropriate devices must have the relevant driver installed on the operating system. Computer drivers are software which interact with and control certain aspects of the hardwa re. Drivers provide a software interface which allows operating systems and other software to interact with the device without the user having precise knowledge of hardware.
Task 4
Company: Advanced Micro Devices URL: http://www.amd.com; http://www.solidworks.co.uk/sw/successes/customerstory.htm?record=Advanced-Micro-Devices&id=4818 So ftware: SolidWorks Industry: Electronics and Mechanical Advanced Micro Devices (AMD) is a semiconductor design innovator which is leading the next era of computer processing and graphics acceleration chips. AMD’s graphics and computing solutions power PC’s, gaming consoles, workstations, servers, and embedded systems. Before using SolidWorks, AMD used to use physical prototype boards to verify mechanical dimensions. However the use of tools in SolidWorks such as 8
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CircuitWorks, - which enables users to share, compare, update, and track electrical design data so users can more quickly resolve electrical -mechanical integration problems, - minimises the amount of physical prototype boards required, hence saving the company thousands of dollars annually. AMD has also adopted SolidWorks Enterprise PDM which synchronises design data across AMD subdivisions in Shanghai, Bangalore, Texas, California and Singapore. According to Jabir Yusufali who is a member of the technical staff at AMD, the company used to email large design files back and forth which “used to take hours to transfer files back and forth among the various locations” . Using SolidWorks PDM solutions, “sharing and accessing files is down to a matter of minutes because the vault and powerful search capabilities have resolved these issues”. Yusufali also said that the system “makes collaboration both more efficient and effective.” Using the CircuitWorks feature in SolidWorks allows mechanical engineers to work with ECAD (electronic computer aided design) data by importing IDF (Intermediate Data Format) files. Using this method, AMD can “more efficiently pinpoint issues and effectively relay that information back to our electrical engineers” which saves time and money. Utilising this approach, “ we can catch things earlier than we would without CircuitWorks”. However the implication of SolidWorks CAD solutions comes with a cost. SolidWorks commercial licenses can be very expensive. The company also has to train its employees in using SolidWorks which can be very expensive and a lengthy process. The initial transfer from using physical prototype boards to SolidWorks may take some time. Despite the drawbacks in using CAD, AMD has reduced its transfer times from hours to minutes by minimising the use of prototype boards, which saves the company thousands of dollars annually, shortened file search times, and improved the collaboration between mechanical and electrical engineers.
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Abdullah Ahmed
Company: Leenaars Marine and Offshore Design BV URL: http://www.leenaars-bv.nl/ ; http://www.solidworks.com/sw/successes/customer-story.htm?record=LeenaarsMarine-and-Offshore-Design-BV&id=4863&scid_sm_bl_leenaars So ftware: SolidWorks Industry: Automotive, Transportation and Marine Leenaars Marine and Offshore Design BV is a leader in the creation of innovative designs for ships, offshore platforms, and marine equipment. The company has played a significant role in the introduction of several new technologies and continues to strive to contribute further in this field. Before incorporating SolidWorks in their p roduction cycle, the company had had its analysis work contracted by a third party company. According to the Managing Director Cees Leenaars, the use of a third party company limited the use of analysis to confirm the validity of a design and did not “cont ribute to evaluating new concepts”. Leenaars Marine and Offshore Design BV have now cut the development time in half since the implementation of SolidWorks. The company has no need to “hire an external consultant” which results in “shorter communications” and “no need for a lot of meetings.” For some projects, SolidWorks has reduced the design time by 40-50 percent, which saves the time of the company immensely. The use of SolidWorks in Leenaars Marine and Offshore Design BV has improved the collaboration between engineers and designers, subsequently improving the work efficiency of the engineers. The Managing Director stated that they “pair a CAD operator with an engineer for each project”, the CAD operator essentially builds the model while the engineer determines the loads and constraints. Both the CAD operator and the engineer can work together and resolve issues. Using this method, Leenaars Marine and Offshore Design BV can assign engineers to multiple projects, thus doubling the output of an engineer. SolidWorks has also helped Leenaars Marine and Offshore Design BV achieve many of its project improvement goals such as reducing the steel weight and introducing many beneficial innovations. The company’s LNG module supports which are the interface between the vessel and multiwheel transporters is up to 15-20 percent lighter and saves the company $450,000 in cost. The company
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also used the FEM functionality in SolidWorks and is now more efficient at analysing designs. The same disadvantages that were present in the last company, also apply here. Nonetheless, the use of SolidWorks in Leenaars Marine and Offshore Design BV has shortened design time by 40-50 percent, doubled the productivity of the engineers, reduced the design weight by 15-20 percent and reduced the lost ships days which has saved customers money.
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Abdullah Ahmed
Bibliography Inc., http://www.inc.com/encyclopedia/computer-aided-design-cad-and-computer-aidedcam.html, [Accessed on 6 November 2014] SolidWorks system requirements, http://www.solidworks.com/sw/support/SystemRequirements.html , [Accessed on 24 October 2014] SketchUp PRO system requirements, http://help.sketchup.com/en/article/36208, [Accessed on 24 October 2014] AutoCAD system requirements, http://knowledge.autodesk.com/support/autocad/troubleshooting/caas/sfdcarticles/sfdcarticles /System-requirements-for-AutoCAD-2015.html, [Accessed on 24 October 2014] Inventor system requirements, http://knowledge.autodesk.com/support/inventorproducts/troubleshooting/caas/sfdcarticles/sfdcarticles/System-requirements-for-AutodeskInventor-2015-products.html, [Accessed on 24 October 2014] Siemens NX9 system requirements, https://support.industrysoftware.automation.siemens.com/certification/ , [Accessed on 24 October 2014] CATIA V6 system requirements, http://www.3ds.com/productsservices/catia/capabilities/design/advanced-surface-modeling/icem-surf/resourcecenter/supported-hardware/ ,[Accessed on 24 October 2014] Pro/ENGINEER Wildfire system requirements, http://support.ptc.com/partners/hardware/current/support/proewf4.htm#system_requirements, [Accessed on 24 October 2014] CAD training tutorials, (2012), http://cadtrainingtutorials.blogspot.co.uk/2012/09/whatsdifference-between-solidworks.html, [Accessed on 28 October 2014] Paper2dwg, http://www.paper2dwg.com/articles/advantage-disadvantage-cad.htm, [Accessed on 28 October 2014] Advanced Micro Devices wiki page, http://en.wikipedia.org/wiki/Advanced_Micro_Devices, [Accessed on 4 November 2014] Dassault Systèmes wiki page, http://en.wikipedia.org/wiki/Dassault_Syst%C3%A8mes , [Accessed on 3 November 2014] Leenaars BV, http://www.leenaars-bv.nl/ ,[Accessed 6 on November 2014] Finite element method wiki page, http://en.wikipedia.org/wiki/Finite_element_method , [Accessed on 5 November 2014] SolidWorks FEA, http://www.solidworks.co.uk/sw/products/simulation/finite-elementanalysis.htm, [Accessed on 5 November 2014] 12
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Rapid Prototyping wiki page, http://en.wikipedia.org/wiki/Rapid_prototyping , [Accessed on 3 November 2014] Genetic algorithm wiki page, http://en.wikipedia.org/wiki/Genetic_algorithm , [Accessed on 3 November 2014] AMD CrossFireX wiki page, http://en.wikipedia.org/wiki/AMD_CrossFireX, [Accessed on 10 November 2014] Nvidia SLI wiki page, http://en.wikipedia.org/wiki/Scalable_Link_Interface , [Accessed on 10 November 2014]
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