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Features List 13
Working to Rules
From CAD User Mechanical Magazine Vol 17 No 04 - APRIL/MAY 2004
Substantial amounts of time can be saved by leveraging on a companies knowledge base for engineering-to-order and customised products.
Let's indulge ourselves in a little bit of fantasy. Let's say we are a bespoke shopfitting company, manufacturing a unique range of quality fittings composed of some standard connections and units that can vary in size from job to job. Let's imagine that our customers share the usual tendencies to slam in orders at the last possible minute, giving us mere days to use their dimensions, design the fittings, produce the drawings and lists of materials to make them - and manufacture the goods. Oh, I forgot to include the quotation based on the customer's measurements, which they will have to sign off before we can go ahead!
If we have to dig out the old drawing board every time we do this, or better, switch on the computer and load the CAD programme, we had better forget it!
Consider an alternative scenario, instead. We load another programme, enter the dimensions of each variable component of the fitting, press a few buttons, and watch the 3D model emerge, from which we can automatically extract the 2D drawings, quotations, BOMs and other documents - all within a matter of minutes!
Far fetched? Far from it! It's all based on the concept of Knowledge Based Engineering. You know what all of the components of the fitting are, you know how to put them together - after all, you have made them in the past -you just don't know what size to make them.
Knowledge Based Engineering consists merely of telling the computer what you know, giving it most of the information it needs to build the fitting, so that when you have the final information available -the dimensions and any other variable information - it can go ahead and finish the job.
Sounds simple, doesn't it? In fact, it is! It doesn't even need a CAD expert at this stage, as all of the hard work was done by the designer for the very first project. I may even be flying in the face of experience and reason by saying that the firm's rep can be trusted to complete the process.
It all starts, of course, with the SolidWorks model, the original design for
the fittings in question - or for any other component or assembly for that matter.
From here on it follows a set of rules for setting up the knowledge acquisition
and storage process, and the creation of another set of rules that have to be
adhered to, to complete each successive design project.
Form Design is an interesting sub-routine, allowing the user to set up a Gantt chart that will provide a logical path through the specification process, and includes decision points, where paths will diverge depending upon the options chosen. User Forms created by the DriveWorks Administrator capture the design of the product, and assign the rules that will affect it, determining which ones the user can specify and drive.
When we come to add the customer's dimensions and specifications for each part, Design Specification drives the parameters of the part, using intelligence built in to each control on the User Form. These controls can be enabled or disabled dependent on choices made elsewhere, or populated dynamically to reflect options selected from previous selections.
Configuring the Product
We can now enter the Design specification, adding such things as height, width, material, power supply required - if you build a bigger model, rules can be established to add in a more powerful power source - and any other special features. To ensure that the correct components are being selected we can even add images to the design specification form.
Because we have included attributes that include prices, price/quantity breaks, and so on, the software can produce a quotation from the input data as soon as it can print it out. Having checked it out and found that some changes need to be made, we can return to the Design Specification form to put them into effect.
The quotation information can be appended to the Master Design Sheet that controls the product, or saved in any file type that can be used in Excel. Other documents that can be created at the same time include cutting lists, purchase requisition notes and detailed BOMs, which can also be saved as separate files.
Besides the speed at which the supporting documentation can be produced their quality is guaranteed, and they conform to the standards set up by the company, notwithstanding the experience and capabilities of the product specifier. And here we come to the meaty bit! Having specified the part - which, because of the rules we have already established, is guaranteed to be capable of being built - we can invoke the services of SolidWorks again, which makes the necessary changes to all of the parts and assemblies that we have specified and automatically creates the 3D model, from which we can extract the 2D drawings.
We don't have to root out the original design engineer either to accomplish this, as the process is automatic once the specifications have been added, even down to the way in which the different design views and elevations are placed on the drawing sheet - with 3D rendered drawings neatly in place as well.
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