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Discussion Starter · #1 · (Edited)
In engineering simulations are established as a very useful tool for research and development (usually first stages of, or pre-development). Being quite active in this and also very interested in watches (well, all kinds of mechanisms), I would like to know more regarding the state of the art in the watch industry.

The usual practice wrt mechanisms is to first simulate the kinematics and then proceed with the dynamics. The former is trivially achieved with CAD software tools whereas the latter requires codes that can simulate the Multi-Body System dynamics of complex mechanisms, often including representations of certain parts modelled with the Finite Elements Method. The degree of accuracy achieved by advanced MBS & FEM packages is exceptional, i.e. adequate to achieve excellent correlation results with the experimental data and thus able to signifficantly reduce development time and costs. Furthermore, it allows for investigations regarding advanced technical solutions that permit evaluation to a virtual engineering level without the use of costly prototypes.

I am wondering whether such techniques are employed by the manufacturers and to what extend. Any ideas?

PS: I know that my query is highly specialised, however I have been impressed by the wealth of knowledge presented by members of this forum. I am reasonably optimistic that someone will be able to provide information on the subject.
 

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Probably not, other than the most basic 3D model to see just how sloppy the tolerances can get before things stop working.

Most movements today, even the "new" ones have the same geometry and layout as much older designs. These old designs date back to well before the era of computer simulation and modeling.

Some of the modules that have been designed lately and grafted on to various movement may have had more modeling and computer proto-typing done during their developement.
 

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Discussion Starter · #3 ·
Thanks for the reply Lysander.

A few months ago I attended the Doktorfest of a friend and former colleague of mine in the ITM (Uni-Stuttgart). While looking for his next appointment (related to MBS simulations) he had been approached by an Ingenieurbuero in Switzerland which (allegedly) provided technical consultancy services to Rolex. Unfortunately my friend is not a WIS and he did not proceed with the contact any further; the story did get me wondering though.

Whereas the technical innovations in the fields of material science and simulations tools are nothing sort of spectacular, the advances wrt the efficiency and accuracy of movements are not very impressive if one considers the years of development in this field. I reckon that osmosis between engineering fields is necessary on order to advance the state of the art through technology transfer. What is really dissapointing is the fact that the technical expertise for the improvement of the movements is already available (and that has been done at the expenses of other sectors), however the manufacturers appear mentally lazy in that respect.

Perhaps I should submit an 'escapement optimisation investigation' paper for the next ECCM.
 

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I don't think they are "lazy," just very, very conservative.

The basic watch movement, as it developed in the middle of the nineteenth century, is a very reliable and easy to manufacture item. Changes in the mechanics of the watch won't improve accuracy, but might adversely affect the reliability. Given the high cost of development and tooling for a completely new movement, manufacturers are unwilling to take any risk.

Changing materials (but leaving the shape alone) allows minor improvements, without major risk.
 

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Discussion Starter · #5 ·
Admitedly, the term 'lazy' was rather unfair. I have to admit that the basic movement layout is well resolved and evolutionary developed to a satisfactory level. Proof of the concept is the use in other mechanisms that need to operate on a time measuring basis without the use of electronic elements (this is a paper I reckon you will find interesting: http://www.smartmaterials.ca/wp-con...7-108_controllablehinge_vtokateloff_et_al.pdf).

I am still inclined to believe, thought, that a detailed dynamical analysis of the system would allow for improvements. Of course the paragons of inaccuracy are difficult to model, yet the state of the art in simulation techniques can permit very precise representation of the system dynamics via mathematical modelling. I would expect a detailed analysis to focus on the strain calculations and proceed to friction reductions through not only use of new materials but also topology optimisation of the movement elements (among other possibilities). In that respect, the proposed modiffication would not be revolutionary but evolutionary instead. Think of it as a switch from the current heuristic evolution approach to a proper engineering development process.
 

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Part of the problem is the simple question of what is it that you want to improve? If you want a more accurate, longer-running, cheaper watch, we've already got that. It's called a quartz. So what engineering problem can we define with regards to the design of a mechanical watch that isn't already answered by that solution? If we're looking to improve our mechanicals simply becuase of our irrational attachment to mechanical movements, then we've already strayed from a proper engineering development process to some degree.
 

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Discussion Starter · #7 ·
Hi Rob!

The objective is to improve the accuracy and autonomy with purely mechanical elements. Is it not that for the same reason (pretext, if you like) mechanisms such as the tourbies, more so the gyro-tourbies like the one from JLC, have been developed? Or the constant torque chain transmission by Lange?
 

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Actually, troubillions are popular (and prized) more because of their inherent complexity and the visual appeal of the rotating balance. There's no evidence (that I'm aware) that tourbillions are inherently more accurate (although since they're so rare and expensive, the quality of the whole watch tends to be higher).

In the world of watches, there's a reasonably sized group of people who prefer (and will pay the mark up for) mechancial movments. There's a substantially smaller group of people who care that their mechancial watch be accurate to greater then +/- 5s per day. Within <that> group is an extremely small subset of people who'll pay the price of having the most accurate mechancial watch possible. So yes, there is a market that might be exploitable. But is that worth the investment of time and energy to attempt to reinvent the wheel? Doubtful. If there's any true innovation in watch design, it'll come from independant enthusiasts. The co-axial escapement is a good example of that.
 

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The original idea behind the tourbillon was if a pocket watch was stored in the vest pocket, the rotating balance would cancel out all the positional variation in the plane of balance rotation.

However, when a watch is put in a vest pocket, it is almost always pendant up, as the fob or chain attached to the pendant sticks out the top of the pocket for access, so the idea was based on a false assumption.

A three-axis tourbillon would be interesting exercise, but impractical due to thickness, and it has been done. The only improvement there would be one if scaling it down.
 

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Discussion Starter · #10 ·
Although the effect of the tourbillon on the accuracy is disputable, the motivation for the introduction of the device is not. In similar manner, other technical improvements (or innovations) that were introduced in the past have been deviced in order to improve the accuracy and autonomy of the movements. Of course, since the core design works efficiently, the developement of complicated mechanisms is nowadays more art- than performance-driven. However, the technical improvements I had in mind are evolutionary and functionalistic. Furthermore, considering the utilisation of simulation techniques, the process would not be as expensive as it may appear to be. [Actually, the prime objective in the industry for the use of such methods relates to cost reduction.]
 

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Seems to me you want to do something primarily for the sake of intellectual curiosity. Normally there is nothing wrong with this and we would still be living in caves without such enterprise, however in this case you are proposing an expensive monetary adventure that will have little or no chance for economic payoff. The individual timepiece (watch) has been perfected with the invention of thermo-compensated quartz movements accurate to seconds a year and even more so with the radio controlled watch tied to atomic clocks. But, you say, you want to use the most modern scientific and engineering advances to improve mechanical watches. Considering that of the approx. 1.3 billion watches made yearly, only 2 or 3 per cent are mechanical where is the economic incentive unless you think that novelty will sell enough "perfected" watches. Consider the current COSC certified watch, at the worst it will be off 6 seconds a day, (6 /86400= 0.0000694). How much improvement do you think you can come-up with?
 

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Quite. If it is possible to have a fifty year old watch of modest type that can still maintain accuracy within a couple of seconds a day, then you are knocking at an open door. You don't find many teflon bearings in spinning wheels. there is a reason for that. This is a fully matured technology where innovation, if there is any, is purely for marketing and the average customer is so stupid that they buy a five bob watch in a thousand pound shop because it is expensive. FEA etcetera is great for designing aircraft (as long as it isn't a Scairbus;-) but the watch industry can live without it.
 

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Discussion Starter · #15 ·
First of all, thanks to all gents for the kind replies. :)

I should clarify that I have never considered the subject as a potential business venture therefore have not thoroughly examined the economical aspects. However, judging by my experience in the field of simulation techniques I can verify that the needs for simulations in the R&D phases come from very diverse fields, for reasons that relate to cost apart from the obvious technical advantages. Regarding the potential benefits, I would expect advances in the areas I have already mentioned but also increased performance with respect to shock resistance (a major disadvantage of mechanical watches).

Perhaps I view the whole subject in a prejudistic manner due to my obsession with engineering and professional background. However I am honestly qurious about your thoughts. Do you consider the achieved accuracy, and the fact that it has been realised many decades ago without recent progress, satisfactory? What about robustness of the movements? And would you be willing to pay more for a technically superior movement? [I would.]

Cheers,
Basil
 

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Discussion Starter · #17 ·
You might find this interesting from HH
Société Suisse de Chronométrie: reinventing the wheel http://journal.hautehorlogerie.org/...uisse-chronometrie-reinventing-the-wheel.html
Very interesting link, indeed. :thanks

Using Matlab for the applications described is a good idea. As far as the article is concerned, the incestigations described are primarily related to gear wheel design and kinematics. Of course, solid mathematical background provided, these can be conducted by hand, which is not the case in other (primarily numerical) solutions. Still, it is nice to know that there is some progress.
 
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