Talk:Damping (disambiguation)

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Critically Damped[edit]

Can someone explain to me how a critically damped system would converge faster when in fact it is multiplied by t in part of the solution? Since the over-damped system is a decaying exponential times a constant it would decay faster than the exponential time a positivally growing constant. —Preceding unsigned comment added by 72.84.196.167 (talk) 01:40, 29 October 2008 (UTC)[reply]

Underdamped[edit]

So an underdamped door-closer will "bounce" on the way to being closed?  Should mention this to complete the analogy. jyavner 21:31, 26 November 2005 (UTC)[reply]

I think the door-closer analogy is a bit confusing. A door-closer's motion is only described by a second-order differential equation if there is a spring involved, as well as the mass and damper. If it's just a mass and damper, then it can be described by a first-order differential equation and it cannot be described as over-, critically-, or under-damped. Perhaps a spring should be mentioned in these analogies? Dkraemer1 19:43, 11 January 2007 (UTC)[reply]

Consider a door with no spring force. Open it, release it from rest... and watch as nothing happens. This is just a regular door. (CHF (talk) 23:46, 14 June 2009 (UTC))[reply]

Gif: Underdamped[edit]

I think it's probably a good idea to alter the current gif-file a bit, in a way that the system stays in 'rest' a little bit longer'. Just add a frame or 2, 3 with the end of the simulation I purpose. Right now, the thing doesn't seem to stop at the end of the simulation. Anyone able to alter this? --Flekkie (talk) 21:16, 25 May 2012 (UTC)[reply]


Over damped[edit]

Is it worth including that over-damping is 'aperiodic' motion? Given the necessary initial conditions the motion can pass through the equilibrium position once (but only once), i.e. start off with a positive displacement, pass through zero, then converge to zero from the negative side. It doesn't always look like exponential decay as in the diagram. (source: 'Vibrations and Waves in Physics', Third Edition, Iain G. Main) —Preceding unsigned comment added by 87.102.123.249 (talk) 11:56, 23 January 2010 (UTC)[reply]

Image change[edit]

I've replaced Image:Springdampermass.png with Image:Mass-Spring-Damper.png, which I originally drew for Nondimensionalization. I also changed the symbol used for the damping constant in the article from R to B to match the image. Of course, it would be easy to create a variant of the image with a different symbol and without the external force arrow, but I feel it looks good enough as it is. If you disagree, please say so (or just revert me, it's no big deal). —Ilmari Karonen (talk) 23:03, 24 January 2006 (UTC)[reply]

Move from my talk--Light current 21:22, 27 May 2006 (UTC)[reply]

I think that the figure looks great, but it is a little bit confusing on one point: x should be defined as positive in one direction. Showing x going both ways makes it difficult to figure out the direction of the spring and damping forces. Dkraemer1 19:46, 11 January 2007 (UTC)[reply]

Notation changes at Damping[edit]

I notice you (and 72.132.7.159, which I assume is your IP address) have been editing Damping to change the notation used in the article, in particular changing the sigmas used to denote the damping factor to zetas (or, in earlier edits, to alphas). While I appreciate your attempts to improve the article, plase note the following:

  • The article currently has consistent notation. Please keep it that way. If you change, for example, some of the sigmas to zetas without changing them all, the article becomes very confusing and potentially misleading. When making notation changes like this, please either a) use the preview button to check your edits, and only save after you've checked that you've changed all the symbols consistently, or b) copy and paste (the relevant sections of) the article to the talk page or to a user subpage for drafting, make the changes there, and then copy the result back.
  • The symbol zeta (ζ), in particular, is already used in the article to denote the damping ratio (σ/ω0). If you wish to use it for the damping factor, you need to choose some other symbol for the ratio.

In general, it's better to discuss changes like this on the talk page first before making them. That way, we can choose a consistent notation that all editors find appropriate and avoid needless back-and-forth edit warring. It also makes it less likely for someone to mistake your edits for sneaky vandalism. —Ilmari Karonen (talk) 20:38, 27 May 2006 (UTC)[reply]

72.132.7.159 is not my address. I always log in. The symbol for damping factor is zeta. Someone else has been changing the symbols. I intend to revert the page and change the so called 'damping ratio' symbol to sigma as it should be.--Light current 21:17, 27 May 2006 (UTC)[reply]
Actually, it seems you introduced the use of σ (it used to be α) for the damping factor yourself. The note about ζ being used for the damping ratio was added earlier by 212.225.34.56. (Note: Both of these diffs combine multiple consecutive edits by the same user.)Ilmari Karonen (talk) 23:33, 27 May 2006 (UTC)[reply]
Yes it does appear that I changed them from alphas to sigmas whilst meaning to change them to zetas. I obviously got confused between the two greek symbols 8-(.
However, zeta is the most commonly used symbol for damping factor and I think thats what it should be 8- ) Sorry for the confusion!
I dont remember introducing the note about zeta being used as damping ratio. I think that may be where some confusion arose as I may have misunderstood that edit to mean damping factor. So its not actually an edit war going on its just basically my mistake(s)! Sorry! I hope this clears up the confusion.
I suggest the symbol for damping ratio should be sigma. (I dont know what the convention is on that) 8-|--Light current 01:09, 28 May 2006 (UTC)[reply]

72.132.7.159 appears to be in agreement with me and has been changing the sigmas to zetas. But he didnt change them all. I changed the ones he missed. You reverted all his recent changes to the page. So Im not quite sure where we are now. I think we need to revert to a much earlier version around 18 May and go from there. What do you think?--Light current 01:50, 28 May 2006 (UTC)[reply]

I've been reverting any changes that left the notation in an inconsistent state — I don't personally care whether the symbol for the damping factor is σ or ζ, as long as it's consistently one or the other. The article is right now essentially same as it was on 18 May; the changes since then are mostly cosmetic ( to ω0 etc.). In any case, if no-one objects to the notation change, I'd be happy to do it for you; in fact, I've already done it on my user subpage (took me all of two minutes with a bit of javascript). What do you think? —Ilmari Karonen (talk) 12:05, 28 May 2006 (UTC)[reply]

Yes thanks for taking the time to do that 8-). Ive copied it from your sub page now and it is correct IMO and consistent. One thing that is bothering me tho' is the introduction of the 'damping ratio' early on and its inclusion in the system description. THis tends to confuse the issue. The equation is usually quoted using the damping factor only. I intend to change this soon. THanks for your help. 8-)--Light current 14:01, 28 May 2006 (UTC)[reply]

I see the conflict. There seem to be conflicting definitions of "damping ratio", not just different symbols. For the most part, this article seems to differentiate the two properly by calling one the damping "factor" and the other the damping "ratio". Modern control theory states that the damping ratio is used to determine whether the system is over, under, or critically damped. Using the equation , there are two ways to define the damping. I will denote the damping ratio as it is currently defined in the article, though I personally use them the opposite way.
Definition 1:
This definition really doesn't give much meaning to the term, requiring it be compared to the natural frequency.
Definition 2:
Rather than comparing it to your natural frequency, your system is always critically damped when . This seems to be much more convenient by definition, so the roots of your system will be found using the quadratic --Mysteryegg 16:37, 20 July 2006 (UTC)[reply]

I think that using zeta, as in , is the way to go. That is what appears in the article currently, written as . However, the name for this parameter is given as the "damping factor". This is not the standard in engineering literature, from what I've seen. It should be called the "damping ratio". A quick look at the Wikipedia entries for damping ratio and damping factor confirms this conclusion. Dkraemer1 20:34, 11 January 2007 (UTC)[reply]

I want to propose a constant change for the damping coefficient from capital B to a lower case c. This change would put the article in line with the standard notation taken in most engineering programs. Also, pertaining to the zeta conversation, zeta is the appropriate symbol as far as I've ever seen in all of my engineering courses and textbooks. --Barkman 17:34, 15 February 2007 (UTC)[reply]

Pictures[edit]

I dont think these pics are particularly helpful (sorry) . There are some better ones you could use over at tuned circuit I think! 8-)--Light current 00:22, 5 June 2006 (UTC)[reply]

--Mysteryegg 20:16, 23 July 2006 (UTC)[reply]

There is one specific problem with the diagram with the red, green, and blue lines comparing under-, over-, and critical damping. It shows the critical damping case with the greatest initial negative gradient, whereas in fact it should be the under-damped case. The less damping, the faster the system initially heads toward the point of stability: the problem of course is that if insufficiently damped it overshoots. A replacement diagram would be good but unfortunately I didd't see anything useful at tuned circuit. —Preceding unsigned comment added by 63.229.11.118 (talk) 16:18, 7 May 2009 (UTC)[reply]

Dampening is not Damping[edit]

Hey what's the deal? I added an explaination about the differences between dampening and damping since it is a very common mistake and someone wantonly obliterated it. dq 23:21, 12 June 2006 (UTC)[reply]

The two words are obviously different 8-|--Light current 23:23, 12 June 2006 (UTC)[reply]

Do you watch any of the Star Treks? They get it wrong all the time. Most engineers get it wrong too if they are not vibration experts. dq 02:49, 13 June 2006 (UTC)[reply]

Im not a vibration expert. I dont get it wrong 8-)--Light current 03:05, 13 June 2006 (UTC)[reply]

Unfortuneately, not everyone is like you. Maybe we need a third party is this discussion? dq 16:23, 15 June 2006 (UTC)[reply]

I dont think so! But please ask anyone else for thier opinion 8-)--Light current 16:29, 15 June 2006 (UTC)[reply]

Agree that this should be in the article. I wish people would stop removing stuff like this.

Dampening is "To deaden, restrain, or depress" while damping is "The capacity built into a mechanical or electrical device to prevent excessive correction and the resulting instability or oscillatory conditions." See also dampening, dampening effect. — Omegatron 21:57, 27 June 2006 (UTC)[reply]

I think this may be largely a matter of opinion but IMO, damping is the correct scientific term. Dampening means to make something damper (ie wetter)--Light current 22:10, 27 June 2006 (UTC)[reply]
I got mine from a dictionary. It has multiple meanings. — Omegatron 00:53, 28 June 2006 (UTC)[reply]
So did I. In over 30 years in electronics, I have never heard the term dampening used, nor have I seen it in any of the hundreds of books I must have read over that time. If you can find a reliable respected reference source using the term 'dampening' to describe what we are tring to, then I will accept it for inclusion 8-)--Light current 07:11, 28 June 2006 (UTC)[reply]

Both terms are gerunds. Their roots, Dampen and Damp, have several transitive and intransitive definitions. Among the "control/limit" definitions, dampen and damp can seem very similar by denotation. The gerunds, however, are not usually used in the same connotation. Only damping can relate to control theory or oscillations. In other words, if you damp a second order system to keep it within stable parameters, you are dealing with its damping, which is now a term describing a field of study. Dampening is not used in its gerund form as often and more often relates to suppressing abstract concepts, like dampening a political movement. Webster uses "The heat dampened our spirits" as an example.

You might look at the words' origins to confirm this, but you might suggest that all physical properties are damped and abstract properties are dampened. However, I'm more inclined to believe that damping requires indirectly affecting oscillations, etc. by controlling some damping factor that it depends on. Therefore dampen is used for taking direct actions to "silence" the direct object where there is no differential equation to describe the situation. This could justify musicians' use of dampening when they just use their hands to dampen the sound. Supporting the physical/abstract theory, for example, you might damp a fire, or use "inertial dampers" in Star Trek, but dampen a mood. The latter theory might be supported by the same examples saying that you are limiting the oxygen factor that fire needs or increasing the stiffness parameter in a spring, while there is no differential equation and thus no damping ratio to describe direct intervention.

My conclusion is: damping is a mathematical concept describing a means of affecting some natural response with a constant damping factor, and dampening is a direct intervension of the scope of some concept with no defined consistant damping factor.--Mysteryegg 20:11, 23 July 2006 (UTC)[reply]

Oh it's also interesting to note that a "damper" can relate to either term.

The importance of gamma[edit]

Can anyone say why this parameter has been introduced? It just seems to complicate the picture! I mean what does it represent anyway? 8-(--Light current 21:12, 27 June 2006 (UTC)[reply]

It's the exponent you solve for. In any case, it's useful to let the reader know that the whole system can be characterized by a single complex parameter, at least to anyone who is familiar with exponentials in the complex plane. Knowing that the solution is of the form immediately tells me that, depending on the parameter, the solution will look like exponential decay possibly combined with oscillation.
I'm not quite sure if your explanation helps... I'm not even sure the information on the page about gamma is correct; it is confusing to say the least. I have information from a textbook source that says the amplitude at time t is , so I'm not sure what x represents, but apparently not x(t). It may be something pertinent, but I believe the equation for A(t) should at least be included in the page, possibly replacing x. I thought x is the displacement, but the exponential equation doesn't make sense for that, besides, it's already given by . I also believe is misused other places. For example, on this page, , while on the page for Damping ratio it lists , meaning . Are that true, or are there mixed variables here? This needs to be clarified. On a side note, in the main equation F=-cv, is c the most commonly used variable? I have seen it more frequently as F=-bv. These variables need to be clarified and cleaned up in this and related pages, or at least mention the differences to avoid confusion. Thanks. -- 204.52.215.104 Feb 18, 2009. —Preceding unsigned comment added by 204.52.215.104 (talk) 00:28, 19 February 2009 (UTC)[reply]
By the way, have you been leaving the notation in an inconsistent state again? You really should work on a userspace copy rather than keep making these incremental changes to the "live" version of the article. (Actually, I took a closer look at the history and it looks as if there's been something funny going on with the equations for quite a while. I'll need to dig up some older versions and see if I can straighten it out.) —Ilmari Karonen (talk) 08:42, 28 June 2006 (UTC)[reply]

THe page history shows that it is not I who has been tinkering with the equations (lately).

THe introduction of gamma is confusing and uneccesary to the explanation (especially when it doesnt represent anything tangible). I have never seen gamma quoted in these sorts of equations before and I suggest removal to simplify page. 8-|--Light current 09:01, 28 June 2006 (UTC)[reply]

Units[edit]

Please add appropriate units for variables and constants - discussion of physics/mechanics topics is greatly improved by including a consistent set of units.

Door-closer Analogy[edit]

In answer to jyavner, who inquired regarding a possible bounce for an underdamped closer: yes, an underdamped closer would "want to" bounce, because it would reach the closed position with nonzero velocity. It is also worth noting that a critically damped closer might suffer a bounce as well, if the person gave the door a sufficiently large initial shove (i.e., a sufficiently large initial velocity in the "closing" direction). Critical damping does not imply that there is no crossing through the equilibrium state; whether the static equilibrium position is passed or not depends on the initial conditions. Furthermore, though I do not design these devices, I strongly suspect that that they are designed to be (highly) overdamped rather than critically damped for precisely this reason - a sufficiently large amount of damping makes it impossible for a person to slam the door. All closers in my experience appear to exhibit this behavior. (I am not including those two-way swinging doors between restaurant dining rooms and kitchens, which are clearly underdamped, and have little or no intentionally included damping.)

In response to Dkraemer1, who brought up the subject of springs and the order of the ODE involved, the door closer itself must contain a spring element. If there were no spring, the door would never move on its own, and it would never "seek" the closed position. The closer+door system is indeed, therefore, a second-order mass-spring-damper system. It may also be worth noting that the spring is not at its equilibrium position when the door is closed; rather, it is somewhat deflected, so that the door is held in its closed position with some (nonzero) force.

The most important thing that needs to be said (and currently isn't) regarding the critical damping case is that it gives the fastest possible return to a state of equilibrium.

For all of these reasons, I propose removing all mention of door closers in connection with critical damping and inserting language making clear that critical damping produces a system with the fastest possible return to a state of equilibrium. Tpower27 21:08, 6 June 2007 (UTC)[reply]

Merger proposal[edit]

I made a full revision to this article, added some more formulation and a picture comparing the different system behaviors. I feel that there is no need for a separate article for Damping ratio, as there are duplicate explanations and the understanding of the damping ratio should be favored by including it in the [[Damping] article. So, I propose to merge Damping ratio to Damping. - Nmnogueira 11:35, 21 September 2007 (UTC)[reply]

  • Support - For the reasons stated above - Nmnogueira 11:35, 21 September 2007 (UTC)[reply]
  • Support - Same reasons. More useful for readers if merged (until damping article becomes bigger). Frédérick Lacasse (talk · contribs) 18:13, 3 November 2007 (UTC)[reply]
  • Support - I agree for the reason that wikipedia is an encyclopedia, and not a dictionary to have a separate entry for every term. However, if it is decided to merge the 2, it should never be separated if the damping article becomes bigger per Frédérick. There is plenty to be said about damping that is not listed in the article, but a standard needs to be set across the board in terms of how detailed and complete a science based entry should be. i.e, the wiki non-science entry of "President of the United States of America" talks about the job responsibilities, origin, election, campaign, term duties etc. it obvious lists some of the former presidents, but does not go into a ton of detail. There are individual wiki entries for each president. (this is obvious not possible), but lets say there was a wiki entry for "President of the United States of America" during George Washington's time...it would be reasonable to include the details of each president in the entry for "President of the United States of America", and not have an individual entry for each president. It would be reasonable, as many years go by, to separate the wiki entry into multiple wiki entries: the position, and the men...Every 4 to eight years a new president is elected, but even past presidents still make news all the time, adding to their wiki entries.

Damping, and most classic sciences are not expanding in the same manner. It's true that there are not wiki entries for every scientific property, and not all have been adequately written in the wiki world. However, the wiki appropriate info for the majority of sciences is well known, and can be found by scanning section headers in physics/engineering/science textbooks. It is more acceptable for cutting edge technologies, such as nano-tech to be split into multiple entries...not damping however.

Lastly, if you are going to merge "damping constant" into damping, you also need to merge "Coulomb damping", "Shock absorber", & "Dashpot" into damping. If there is ever a "viscous damping" wiki created, that needs to go into damping as well. But if you are going to merge these together, it should be done across the board...i.e, "Torsional vibration" needs to be merged into "Vibration", because they have virtually the same relations and equations...but instead of mass for linear, you have moment of inertia for torsional, and instead of x for linear, you have θ for torsional As an engineering student, i would much rather look at one entry for "damping," and see "all" there is to do with damping in one article. of course each section would be titled, and if i searched for something specific, like "damped natural frequency", "damping" would still come up as a result if it is included in the damping article. That would be much better then flipping through multiple wiki entries on very similar topics... —Preceding unsigned comment added by Cheeto81 (talkcontribs)

automobile suspension damping[edit]

re: "An automobile suspension has a damping near critical damping (slightly higher for "hard" suspensions and slightly less for "soft" ones)"

This statement is a touch misleading. Automobile suspension damping ranges from approximately 0.25 for passenger vehicles (ride softness) to 0.7 and higher for racecars (all-out handling). The relationship between ride quality (low damping ratio) vs. handling (high damping ratio) is relatively well studied. —Preceding unsigned comment added by 129.82.18.94 (talk) 20:08, 12 December 2007 (UTC)[reply]

strongly OPPOSE merger.....Practically the people search both the stuffs for different purposes. —Preceding unsigned comment added by 129.175.82.248 (talk) 08:46, 1 February 2008 (UTC)[reply]

merge Q factor with damping[edit]

As far as I can tell, the Q factor and the damping ratio are 2 ways to measure basically the same thing (see Q factor for the simple equation between them). I think they should be merged into the same article. Since it looks like "damping ratio" is going to be merged into this "damping" article (see above), I guess Q factor should (sooner or later) be merged in as well. --75.19.73.101 (talk) 10:02, 16 December 2007 (UTC)[reply]

  • Oppose - It might make sense to merge Q factor with damping ratio, since they are closely related; or to merge damping ratio with damping; but not both; or to make damping ratio a disambig page to go to either Q factor or damping. This article on damping is more about the process and different regimes of damping, not about the general number that characterizes the behavior of certain physical systems and differential equations. The article on damping and the article on Q factor have little in common, and should stay that way, in my opinion. Dicklyon (talk) 02:45, 17 December 2007 (UTC)[reply]
  • Oppose - No, they're not the same thing and are used for different purposes. 202.89.188.44 (talk) —Preceding comment was added at 15:16, 25 January 2008 (UTC)[reply]
  • Oppose, weakly - Yes, they are two ways to measure the same thing, but there is preference for different in different fields. Q originated in electronics and is used more in engineering, and for sharply resonant, underdamped systems; many of the Q formulas are approximations only valid for that regime. Whereas it seems to me damping ratio is used more by physicists, mathematicians, and in control systems theory. I guess they could be treated in the same article, but what would we call it? I guess I favor merging Damping and Damping ratio and leaving Q_factor separate, but mentioning both numbers in both articles and providing conversion formulas. --ChetvornoTALK 00:18, 26 January 2008 (UTC)[reply]
  • Strongly Oppose - Different fields, different applications. —Preceding unsigned comment added by 220.233.17.28 (talk) 12:26, 26 May 2008 (UTC)[reply]

Merged Musical Damping[edit]

The "Dampening" article was exclusively describing musical damping, even though it used the term "dampening". It seems the more common usage is to call that damping too, dampening seeming to be a much less common way to refer to it, if Google hits on musical terms mean anything. I could see this stuff belonging in a "Damping (music)" article possibly, but the concept is pretty much the same as it is in physics and control systems, and the other article was pretty short, so I just merged. The material is not well integrated right now. It occurs to me that you might use the musical concept to help explain the physics concept, killing two birds with one stone. Gigs (talk) —Preceding comment was added at 04:54, 26 March 2008 (UTC)[reply]

I think this article would be improved if the musical damping section were moved back to a separate page. All the musical examples are basically cases where the musician wants to totally suppress the sound/vibration and therefore is not a particularly interesting example of the physical damping phenemona. Similarly, if you are mainly interested in these musical techniques, examining the formula for harmonic oscillation is not going to be very interesting either and is likely to be confusing. So while musical damping is related to the physical/mathematical damping described on this page, it really doesn't fit. It is like having Poaching An Egg section in a Phase Changes of Matter page because both involve boiling. 71.234.28.244 (talk) 13:37, 23 July 2009 (UTC)[reply]
I agree. I think we should undo the merge, and put the musical stuff back at Dampening, or possibly move it to a better name like Damping (music). As discussed above, these terms are not synonyms, at least in the context of the definition used in this article, which is the more technical meaning. Dicklyon (talk) 15:50, 23 July 2009 (UTC)[reply]

Mistake in graph?[edit]

The graph [[1]] doesn't look right to me. Surely the green line and the blue line should not cross as x decreases to zero. And the 3 lines should all have the same gradient at t = 0, because the motion there (when the velocity is small) depends only on the mass and the spring constant, not the damping coefficient. --Occultations (talk) 12:04, 18 March 2009 (UTC)[reply]

Yes, the figure comes with matlab code, and he plotted the wrong functions. Maybe I'll work on it... Dicklyon (talk) 15:57, 23 July 2009 (UTC)[reply]
Here is a source with the correct equations. Note that that curves start out cosine-like (zero velocity) and all have the same curvature (acceleration) at time 0. Dicklyon (talk) 16:56, 23 July 2009 (UTC)[reply]
OK, it's fixed. Dicklyon (talk) 08:54, 2 August 2009 (UTC)[reply]
That's much better. Could I suggest that the units along the the time axis be cycle times rather than seconds. I would do it myself if I knew how. Occultations (talk) 17:50, 4 August 2009 (UTC)[reply]
It's actually units of time constants, or radians of natural frequency, or t*omega_0. What would you like me to label it? Perhaps the latter? Dicklyon (talk) 00:06, 5 August 2009 (UTC)[reply]
I see you've labelled it omega_0*t. I had to think about that before I convinced myself it's correct. And of course it's dimensionless. So that's a lot better.Occultations (talk) 16:50, 7 August 2009 (UTC)[reply]

Moving to Damped harmonic oscillator[edit]

I would like to move this to Damped harmonic oscillator, since that is really what this page is about. It might help avoid the merging problem with Q, for instance. It also fits in as a 'subpage' of harmonic oscillator. TStein (talk) 05:10, 9 May 2009 (UTC)[reply]

  • Oppose – I hadn't noticed this old unsupported move proposal before, but I like the current title better, just because it's simpler and a bit more general. Dicklyon (talk) 22:23, 19 October 2009 (UTC)[reply]

Damped simple pendulum with forced motion.[edit]

I think there should be an example of a damped oscillator with forced motion. Namely the damped simple pendulum as it is the most easiest example ever. Also, I think that this will add a new dimension to the article as this aspect is not discussed. —Preceding unsigned comment added by Gustav Ulsh Iler (talkcontribs) 22:20, 19 October 2009 (UTC)[reply]

Definitely a good idea; the classical diff eq. for a spring/mass/damper, leading to driven solutions, resonance plots, Q factor, etc., would be good to see done out well. Does it exist in some other article already? Here are some good sources to work from. Dicklyon (talk) 22:25, 19 October 2009 (UTC)[reply]

Unnoticed Vandalism[edit]

Around January, someone deleted quite a bit of the article, making much of it confusing. Unfortunately, there is a lot of intervening edits, so I am unable to revert it.67.170.103.34 (talk) 05:07, 14 March 2010 (UTC)[reply]

The text deleted on 27 January 2010 was restored on 14 March 2010. --UncleDouggie (talk) 12:43, 29 August 2010 (UTC)[reply]

Incorrect Diagram[edit]

I am not sure this article should have a picture of a mass on a spring, and it be called a 'damped' system. Dampening is proportional to the velocity the mass would be travelling at, and a spring does not produce damping. A dampener produces damping. A spring produces a force proportional to the distance it is stretched. Someone want to change this —Preceding unsigned comment added by 82.19.28.168 (talk) 16:53, 23 March 2010 (UTC)[reply]

The diagram does not show a damping component. The motion of the block indicates that one is present. Air is a damper. It would be an improvement if a damper component was explicitly illustrated as we have in File:Mass-Spring-Damper.png. --Kvng (talk) 20:40, 22 November 2010 (UTC)[reply]

Dampener[edit]

Dampener should be Damper. Dampener is something that makes an object damp, i.e. wet. In academic literature we just call something that restraints movement a damper. I agree with the diagram could be made better with a visible damper element. Though a non-ideal spring would have some form of energy loss. That diagram can be considered an exagerated case of frictional damping --MobiusPizza (talk) 10:59, 26 July 2010 (UTC)[reply]

Why does "Scratching (guitar)" redirect to this article?[edit]

The word "guitar" does not even appear in this article, so (without reading it) I assume this is an incorrect redirect, and this article doesn't cover the guitar technique of scratching dampened (palm-muted) strings. Damn, I could really use an article on that right now!

Thanks for your attention. If you can fix this, please do!

--Ben Culture (talk) 04:56, 13 September 2012 (UTC)[reply]

Omega and Omega_0 undefined...[edit]

The part of the following sentence from the article which is in brackets seems interesting, yet is worthless to the reader because omega and omega_0 are undefined: "In physics, damping is an effect that reduces the amplitude of oscillations in an oscillatory system (except for mass-dominated systems where \omega/ \omega_0 > √2), particularly the harmonic oscillator." It is not enough to assume that readers will be familiar with maths-symbol norms when writing on scientific subjects. Perhaps someone who knows what these terms are could include ", where \omega is ___________ and \omega_0 is ___________" after the √2? Cheers. 109.145.85.3 (talk) 17:34, 26 April 2013 (UTC)[reply]

I think I have rarely come across a worse opening sentence. It is barely readable and that parenthesis is incomprehensible. WP:LEADSENTENCE says "The first sentence should tell the nonspecialist reader what (or who) the subject is." This is part of WP:LEAD that says, "The lead should define the topic and summarize the body of the article with appropriate weight." That phrase about omega and root-two relates to something that, as far as I can see, is never mentioned again in the body of the article, so has no place in the lead, let alone in a parenthesis that wrecks the opening sentence. If there is any point to that inequality, it should be explained deep in the article, and if it truly turns out to be one of the most important things that can be said about the whole topic of damping, it can be summarised somewhere in the lead. --Nigelj (talk) 19:42, 31 October 2013 (UTC)[reply]
I have rewritten the opening paragraph, as below.

Damping is a linear influence within or upon an oscillatory system that has the effect of reducing, restricting or preventing the oscillations. Viscous drag can do this in a mechanical system, and in electronic oscillators, resistance can have the same effect. A potentially oscillatory variable is damped when a damping influence opposes changes in it in direct proportion to the instantaneous rate of change, velocity or time derivative, of the variable itself.

Any comments and further improvements welcome. --Nigelj (talk) 20:19, 31 October 2013 (UTC)[reply]
I have a few ideas about improvement that I will try to implement soon. My motivation is as follows:
  • Damping does not have to be linear.
  • qualitative and less detailed things (like the typed of damping) should come first
  • article needs to be better linked to other articles.
If it is ok with all involved I would prefer to do this in the article space under the idea that it is holier to ask forgiveness than permission.
-- TStein (talk) 16:24, 1 November 2013 (UTC)[reply]

I have made some changes to the main article that addressed most of the issues that I raised. The beginning of the article is roughly where I would like to see it in the big picture at least. There are still a few duplicate paragraphs in the Linear Damping section that I would like to combine, but I have ran out of time for now. The example used is a little to mathematically heavy for my taste and may fit better with harmonic oscillator. It would also be nice to have a consistent notation. I am afraid that I don't have time to deal with them now, though ;( .

-- TStein (talk) 20:32, 1 November 2013 (UTC)[reply]

Buoyancy force[edit]

Why is the effect of buoyancy force not considered in case of fluids? Shouldn't we notify that mass in this case is the apparent mass?--82.114.171.82 (talk) 17:36, 19 November 2013 (UTC) (Almuhammedi)[reply]

Merge proposal (November 2016)[edit]

This article covers essentially the same material as Harmonic oscillator. While the concept of damping may well apply to other types of systems, this article focuses solely on damped harmonic oscillators, and that topic is already completely covered elsewhere. Had I noticed this article at its creation, I would have nominated it for speedy deletion under WP:CSD#A10 but as it has existed for some length of time and been edited by several editors, I believe the best course now is to find any material in this article that is unique and not already covered at the other article and move it there, leaving this as a redirect. WikiDan61ChatMe!ReadMe!! 14:36, 3 November 2016 (UTC)[reply]

 Done Given that there is no objection, I have redirected to Harmonic oscillator. There was no significant information contained in this article that was not already contained in that article. WikiDan61ChatMe!ReadMe!! 13:37, 16 November 2016 (UTC)[reply]
@WikiDan61: Aside: A10 would have been inappropriate because one of the necessary criteria for A10 is and where the title is not a plausible redirect. --Izno (talk) 18:52, 18 November 2016 (UTC)[reply]

split proposal - Damping & Damping Ratio[edit]

From a perspective of physics vs. engineering, damping and damping ratio describe two separate but related quantities. In its simplest form, damping exists as a form of entropy generation, while the damping ratio is a convenient parameter used in the non-dimensional analysis of an oscillating system. — Preceding unsigned comment added by Antwan718 (talkcontribs) 02:27, 22 May 2018 (UTC)[reply]

But damping ratio is just a way to quantify the rate of entropy conversion; perhaps damping would be a more inclusive topic, but it doesn't sound like a separate topic. Dicklyon (talk) 02:46, 22 May 2018 (UTC)[reply]
In 2016, this version of Damping was merged into Harmonic oscillator, which makes sense given what the content was at that time. Your version that I reverted is here, for reference. It's not clear where it's headed, but let's see more of a proposal, e.g. a draft as a subpage of your user page: User:Antwan718/Damping. Dicklyon (talk) 02:46, 22 May 2018 (UTC)[reply]
@Antwan718: please see WP:SPLIT and tell us what your justification is for this proposal. ~Kvng (talk) 15:08, 26 May 2018 (UTC)[reply]


@Dicklyon: :@Kvng: Damping, could be defined as the process by which a certain portion of the energy in a system is irreversibly lost causing a decaying magnitude trend in the measured response of the system [ http://db.nzsee.org.nz/2011/091.pdf ]. In practical applications damping may be observed in mechanical systems such as those observed in vehicle dynamics [2], electro-magnetic [3], optical [4], dynamic models of atomic behavior [ ieeexplore.ieee.org/abstract/document/1183847/ ], and several other forms of systems. In each of the above listed cases, the energy which is not retained in the measured response is converted to heat, photon emission, or a coupled electro-magnetic field.

Even in the fields which there is investigative analysis of damping, there is not a truly well understood manner which explicitly states how damping occurs; by having the wikipedia entry limited strictly to "damping ratio" it makes the incoproation of other quantification of damping such as the use of a Loss Factor prohibitive. There is a good review article that discusses the relation between damping, damping ratio, and the loss factor phenomena [5].

Dicklyon The largest issue which I see is that from the context of the existing damping ratio article, there is a strict application to only mechanical processes which function based from viscous damping. There are at least two other forms of mechanical damping models: hysteric damping, and Coulomb damping; which can not fit the model explained in damping ratio which is only applicable toviscous damping.
@Dicklyon: The concepts of the harmonic oscillator and anharmonic oscillator are integrally related to damping though the separation of these two models is fundamentally paramount to modeling [molecular vibration].
Yes, I get your point. The current damping ratio and harmonic oscillator models are about viscous, resistive, or linear damping, but there are nonlinear forms of damping such as frictional that lead to anharmonic systems and not covered here. But what's less clear is what your plan is to fix this. It's not clear that the split you propose is the right way. If you present an article or two in the form of user draft(s) we could get a better idea. Your skeletal draft that I reverted did not look promising; you'll need to do more to show that there's a good direction here. There's no reason not to do it in your user space first. When your ready, put a Template:Split tag on the page. Dicklyon (talk) 01:32, 29 May 2018 (UTC)[reply]
We used to have a separate article for Damping. Here's the last version of it before it was merged to Damping ratio. We merged it because there was so much overlap between the two articles. Is there a way to do a WP:SPLIT that avoids this overlap issue? Another option is to rename Damping ratio to Damping and still cover the metric and phenomenon in the same article. ~Kvng (talk) 13:05, 31 May 2018 (UTC)[reply]
Actually, as I pointed out above, that version of Damping was merged into Harmonic oscillator, since that's what it was mostly about. I agree with your proposal to move Damping ratio to Damping and expand its scope a bit, with Damping ratio as a section, and then if it gets to be too much we can consider the proposed split. Dicklyon (talk) 14:24, 31 May 2018 (UTC)[reply]
I have recovered material from Damping to broaden the scope of the lead. If this looks like a good direction to Antwan718 too, we can request the move. ~Kvng (talk) 17:08, 3 June 2018 (UTC)[reply]

Made it a disambig page[edit]

Too many incoming links to the redirect were for distinctly difference specific aspects of damping, so I made it a disambig page. Now the incoming links need to be sorted for what was intended. Could be harmonic oscillator or damping ratio or damping factor or some of those other forms of damping. Alternatively, we could go back to the broad topic article as suggested above in 2018; but we'd still want to review incoming links and get some of them to better places. Dicklyon (talk) 06:36, 22 February 2021 (UTC)[reply]

@Dicklyon and Kvng: I very much agree with Kvng's suggestion to rename Damping ratio to Damping and still cover the metric and phenomenon in the same article. The Damping ratio article actually already does so at this point, so all that's left is to rename. In fact, I proposed this yesterday at Talk:Damping ratio#Damping vs Damping ratio as I'm only now finding out that this option has already been discussed. If you both still agree this is a good idea and/or have any other input, please let me know over there. Lennart97 (talk) 09:57, 3 March 2021 (UTC)[reply]