14 September 2004

The Inventor $1500.00 Challenge – What Result?

 Firstly to all those who participated through the Challenge, thank you it.

 I have explained some of my reason(s) for asking for information in the manner of the Challenge in other documents so I will not elaborate on why here but if you want to know more please go to Document Index or contact me via email or phone (see details below) I will gladly explain.

 There are several components to this work of mine and the information I have has been collected over a long period.   3D CAD vendors, Autodesk dealers and individual users have all been asked to participate at various times with a varying response.

 Individuals have been drawn on in several ways; by directly approaching users I already knew would be willing to participate.  Some came via other contacts passing on the information; some were drawn from the ranks of contractors and others via the Challenge.

 In all cases the same two components were used and in all cases, except for those not using Inventor, the same method of starting each file was used.  All participants, including those using software other than Inventor, were asked to supply their time ‘to 3D model’ and again in all case what I asked for was best repeatable time, not the first attempt.

 Additionally, I personally have put literally hundreds of hours into this type of work and it is against what I have found and the conclusions I have drawn in my trials that I compare the work of others and the vendor’s claims.  This work for me is necessary because vendor information in our market place is scant, is not accurate nor objectively presented or provided.

 FLEXIBILITY is what I believe is the key to good 3D design software and necessary for increased Productivity and Profitability.  The problem with this argument or requirement of mine is that for many the FLEXIBILITY I harp about equates to complexity, and in some ways they are correct, but it need not be.   The objects in the Challenge, others unseen and those in my WEB page, and the methods used to model them I believe demonstrates the point.

 What Result?

 Block_B and the HandWheel can be turned into 3d models from the profiles provided in less than 15 minutes, that’s what I was asking for in the Challenge. For other participants I set no real time constraints the exception here being one group given a two hour time frame in which to complete both tasks.

 Participants’ times for these tasks has a wide range between a little over 30 minutes (one only) to 120 minutes.  Some participants exceeded a two hour period and still others failed to complete the models stopping at the 150 minute mark.

 Several people chose to change the Block_B shape slightly by not adhering to the method I requested be used, that probably increased the time taken by a small amount. And whilst some users failed to model Block_B it was a surprise to see technical people in the Autodesk MCAD channel not complete the HandWheel.

With the exceptions already mentioned, Block_B was done as requested with a number of participants making comment on the bevel that was defined by two curved edges that were not concentric, some even offered a view point stating they would not make something like that! Quoting their different reasons as to why.  As I have replied this was the shape required for the moulding and a sample of the finished product having the Block_B shape and that feature sits right here in my office. ‘The customer should always get what he wants, after all he pays the bill’s’.

 Interesting also to see that both these models were attempted and done by all using similar strategies, with only one exception and that model was not completed.  Methods and the order of events changed but the underlying strategy remained the same, despite the variations available for the creation of both shapes.

 It is also of some note that even though I said I did not require the sketches to be parametrically constrained some still chose to place dimensions on the sketches provided and used additional constraints.

 The methods chosen for creating the spokes of the HandWheel led to the fact that none of the spokes were dimensionally correct at all eight points of the spokes intersection with the hub and rim.  Indeed only one HandWheel modeled had the flat sloped tapered face dimensions correct with a very slight variation in the parallel edges on the curved face of the spoke, a slip of the mouse I suspect.

 In summary; in this round of trials and the Challenge, again I see a consistency that is the root of what I argue is the difficulties software of this type places on shape generation and  3D modeling.

 Each of you will have your own perceptions of what is ‘right and wrong’ and this polarization of thought about ‘how to’ is often reflected in the comments I get along with the models.  I respect this ‘difference’ of opinion, it’s very important, and while it is mostly offered as criticism it actually supports and underlines my comments about the restrictions 3D modeling software like Inventor places on users.

 Perception of shapes and how to create them is a very individual thing, software needs to harness this not impeded it with rules; my central point.  Polarization of thought and process is at the heart and central to the way developers are thinking about 3D design software and this is why it struggles for acceptance ‘it suits only those individuals and tasks that fit the software’s mould’ not the other way round as it should be.

 Again I look at the HandWheels models received and the spoke shape generation and wonder why so, when other ‘more intuitive/simpler’ solutions exists?

 That’s what clunky old 3D modeling software teaches you and it is also why AutoCAD/MDT will remain better in a number of areas than newer 3D modelers like Inventor.  Old modelers like MDT have less ‘capability’, are supposedly too hard to use, but are often better because they let the user do the ‘thinking’ with greater FLEXIBILITY.  It’s knowledge Autodesk has under its nose and after eighteen years of 3D design software development it has not made the connection, even when they have been told over and over again.

 Their mistake; but we’re paying for it in many ways!

 I cannot conclude this paper without mentioning parametrics.  I am sure I will cop flack in this area as many have mentioned it, so I may as well head some of it off now.

 Parametrics are not new to any person with a long association with MCAD.  I have personally used parametrics in conjunction with Autodesk products since the mid 1980’s.  Sure a lot of that was 2D (and 2D and 3D in early AutoSolid/Designer and AutoCAD) and a trial to use to, but don’t forget old and clunky tools teach a user the many basic rules that have formed the foundations of what we now use.

 The other very important thing to learn and understand is that a great percentage of those who believed, after walking out of a ‘wiz bang CAD demo’ in which the demo jock has used parametrics believe it is what they want (the WOW factor).  When reality sets in for a huge percentage it is just not so and the reasons for that are as varied as there are users and as varied as they are for using or not using 3D modeling. All are closely entwined and both 3D modeling and or parametrics applied indiscriminately will slow many a job.

 I do not discount the relevance or importance of parametrics and address it for my customers when appropriate, but it is not want I wanted to know about or re-analyze in these trials, for that purpose I use other methods and tasks.

 FLEXIBILITY is the key component of 3D CAD software that will be utilized by a wider number of users over a longer period of time; that’s what is demonstrated in these trials of mine.

 ‘A Reason’

 R. Paul Waddington.
Proprietor - cadWest
Phone: 61 2 9724 4305
E-mail:cadwest1@ozemail.com.au

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