SECTION G - Project Management for Concurrent Design techniques resulting from 3D Design with Autocad and Autocad LT

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Project Management for achieving Concurrent Design Methods

When an organization has undertaken learning 3D Design, it expects to see reduced design time scales.  Rightly so.
Before these time scale improvements can reach their maximum potential, experience needs to be gained about managing 3D design projects. Project managers with no experience with 3D design projects are susceptible to underachieving on the time-scale benefits for a good reason.

They are trapped by their 2D project management experience causing them to manage the 3D design project in the way they would manage a 2D project. The result is that only a fraction of the timescale improvements that are available from a 3D design project are achieved. Could this be the reason that drawing offices in companies are still uneasy about learning 3D design methods ?

Experience is what drives how a project manager perceives, approaches, and runs a project. It means that 3D project management training is harder than ‘software usage’ training because it needs to be spread thinly across key points of the project duration. Project Management training is one of the design consultancy services offered by 3D Cadcea. Our approach is to provide an experienced 3D Project Manager that is also a 3D CAD designer to work as part of the design team for an agreed timescale. Our representative would contribute on a number of levels. Firstly, to mentor staff that are novices in 3D project management to build up their experience correctly with the their first 3D design project. Secondly, to be available to train the CAD staff while learning 3D design, and thirdly - when not contributing directly to the above 2 aspects - to be a productive 3D CAD designer on the project team to a level that falls within the agreed design consultancy services. We call this service our 'integrated 3D design training program.'

If 3D Project Manager guidance is not undertaken, the Project Manager's '2D experience trap' will continue and the full timescale benefits of learning 3D design go unexploited. Feel free to contact 3D Cadcea with questions about managing 3D designs and project manager training at any time, or visit the ’Other services’ section of this website.

Project manager training to undertake 3D Design projects correctly will lead to drastically reduced design time and development costs of the entire 3D design project in several directions - not just the design phase. The 'block' and 'layering' structures shown in our training material allow items lists / quantities schedules to be produced automatically, and also show a method for the 'model splitting' techniques discussed below in a moment. Significant improvements in design quality are made too - and are also described below. An understanding of how 3D project management differs from 2D projects is essential if project management efficiencies are to be made while managing 3D designs. The efficiencies are outlined below and are more than just the differences in geometry construction methods.

2D Design scenario.

With 2D methods, it is usual to start with a key part of the project and create a detailed "layout drawing." This initial layout is often used as a start point to create the next section of the project, again in detail. This creates a situation that some parts of the project are at a state ready for drawings, or even being ordered and made, while other parts of the project haven't yet received the high level of consideration that was given to the earlier stages. This approach carries a risk because if a problem arises in one of the later stages, it can have a disastrous consequence on the earlier sections that are almost complete. Firstly it could mean very difficult design constraints for the later stages of a design, or alternatively, the loss of many man hours of effort on the earlier stages that subsequently need re-work due to the new considerations discovered at the later stages.

Once detail drawings have begun on 2D designs, there is a psychological obligation to stop evolving the design. If a 2D design does evolve after detail drawings are begun, time is wasted in revising the existing drawings. Stopping the evolution of a 2D design to create detail drawings means it rarely gets the chance to reach its full potential.

Another situation with 2D projects is that design considerations happen sequentially as layout drawings progress, but the design considerations are never fully addressed until the layouts are brought together. This bringing together happens at the end so design problems can still be present in the last stages of the design activity and not be discovered until very late in the project cycle.

Designing with 2D also has a tendency to limit the number of layouts to those that were initially decided; more can be done, but this also causes an additional time penalty.

All 2D layout drawings force CAD designers to hold a lot of the design information in their heads. The risk of ’poor fit’ or inaccurate items quantities is increased because 2D methods are vulnerable to human error. This occurs because 2D methods dictate that the brain must think to an exact scale, which cannot be done. How often have human error mistakes shown up when a new design is put together for the very first time.

By using correct 3D methods, the above situations are avoided. 3D methods are now mature and design advantages stemming from them are very significant.

3D Design scenario. (Correct methods.)

The starting point is for the 3D CAD designer to create a 3D representation of the whole project. During this early stage, the model needs to be kept at a low level of detail throughout so there should not be any significant differences in the level of detail in different parts of the model. A low level of detail means the CAD models would be represented in the broadest terms showing only the "space envelopes" such as how and where things need to be positioned or where events are going to take place. Detail needs to be added in an even manner and the space envelopes re-assessed regularly. Even if an item can be fully defined (like a purchased part) it shouldn't be modeled in detail, until CERTAIN it will be used. Too much detail at this stage wastes effort, not only because computer power is used up, but because the design is likely to evolve and change. Areas that have had time invested with detail are susceptible to being lost when design decisions change. As concepts become more firm, component detail can be increased. At a point when the model becomes cumbersome it will need to be divided. This is the time when an interface point needs to be identified and the interface designed in detail. The model can then be divided at this interface and more detail added to each of the divided models. As detail is added and the models again become cumbersome, the model splitting would continue with another interface being designed in detail prior to splitting. This would continue to happen until each of the 3D CAD models have all their detail. As the sections get divided each section can become the responsibility of an individual 3D CAD designer or 3D project manager. A major model split is also a convenient time to re-asses the project and its impact on customers and other company departments such as creating publicity material, brochures etc. The last stages of the design come with adding a high degree of detail to the items that need it such as drawn parts. Details like chamfers, screw holes, undercuts, etc. When all the assembly models are complete, the drawings can begin.

The risks associated with 2D design have now been reduced as follows:-

The 3D design is dealt with as a whole, and divided in to sub assemblies as the design progresses so there should not be any surprises late in the design. The design has the chance to fully evolve in parallel, so design quality improves. (2D designs, as discussed earlier, are prone to sequential evolution thus missing the benefits of parallel evolution.)

3D methods mean that 3D CAD designers can ensure proper fit and items quantities - they don’t have to rely on holding information in their heads, as is the case with 2D methods. (2D methods do not represent quantities accurately, so they cannot be used for creating item lists.)

The risk of having to re-work drawings is eliminated, and if drawings are done at the correct time, effort is not wasted with having to revise existing drawings.

Cad 3D models remain a manageable size so both the computer speed and thus project speed are kept high.

When all the assemblies are designed, it is a foregone conclusion that they will fit without incident because the assembly issues have already been thought through from the concept stages and the interfaces designed in detail prior to dividing the models. By working this way the problems of looking at outstanding design issues by bringing together two large CAD files - causing very slow computer speed - have both vanished. Deadlines are much easier to meet. If deadlines are tight, the areas needing attention can be flooded with manpower with a full understanding of how the design will assemble. The above method is the only realistic way of achieving concurrent design - to have several pre defined areas being worked on at the same time.

3D Design scenario. (Common but less efficient methods.)

Indiscretions for 3D design project management novices generally lie on 2 fronts. Firstly, to encourage from an early stage the creation of parts with a high level of detail, and assemble them into sub assemblies. Secondly, to start drawings at the earliest opportunity. These two decisions stem from 2D experience and reduce the predicted design time efficiencies as follows:-

The CAD models become cumbersome fairly quickly while the design is still evolving. If a cumbersome design is still evolving after detail drawings are begun, much time is wasted in revising the existing drawings. The problem isn’t apparent at the start of the design. It happens toward the end of the design just when project deadlines are getting critical. Large 3D CAD files will need to be brought together instead of being divided.

As with 2D methods, if models are created in detail and added together instead of divided, design surprises can remain hidden until the time the models are assembled. It is usually at the later stages that models are brought together - just at a time when you don't want 'design surprises.'

Adding models together encourages sequential design because the design only gets considered as a whole at the end. The reasons for sequential progression of the design are similar to the ones cited in 2D situation discussed earlier.

Also like 2D methods, once detail drawings have begun, there is a psychological obligation to freeze the design, so it never gets chance to reach its full potential.

The above points cause pressure on three fronts. Design issues are still present at a late stage because major assemblies come together at a late stage. Slow computers owing to models with great detail, and finally, these first two pressures are aggravated by having imminent deadlines as the project nears completion. Obviously this is a poor situation to be in but is all too common for newcomers to 3D design. Despite the above, for small design projects this method is fine, and for most companies that move to 3D methods, this has been the natural progression route. The way to judge if this natural progression is going to be adequate, is if the computer speed remains moderately quick when handling the full design with all its detail. The ‘3D Design scenario - Correct Methods’ discussed above is the only option if the design is massive such as a housing estate, a hospital, a cruise liner ship, an oil refinery, a chemical plant, a connected group of factory plant machines such as in the food processing industry, etc. It is also the only viable method for a company wanting to pursue concurrent design methods. Feel free to contact 3D Cadcea at any time to discuss any of our design consultancy services and the mentoring of 3D CAD designers and 3D project managers new to 3D design methods.