1. LOL, say that to the building inspector when u r erecting a mickey mouse tower 2. what make u think i haven't thought about this subject before? u think i felt off a turnip truck yesterday and a light bulb came on? 3. what is your objective of this slow-mo video of the critical time when bird hits stringbed? what r u trying to measure?
Found a slow mo video here on the Arc Z intro site: http://www.yonex.com/badminton/z-slash/091105.html Skip the intro, goto "Speed test", then click the movie on the right. 1. My objective is to show the deformation in the stringbed. It is very necessary and critically important in the transfer of energy from bird to string on impact, then string to bird on rebound. Is that agreed? 2.. If so, then I postulate that there is a certain optimal deformation, not too little and not too much, that is best for max energy transfer. From the video, the stringbed appears to deform maximally about 1 inch back, then it rebounds and pushes the bird off. Agreed? 3. I would postulate that if the strings are too tight then the deformation would be less, maybe only 1/2 inch, and if too loose then deformation would be more, maybe 2 inches. Acceptable? 4. Conversely, we can say that if the swing power is not enough, then deformation would be less, maybe 1/2 inch, and if too powerful, the deformation would be more, maybe 2 inches. Follow? 5. Now comes the intuition part: what if 1 inch was the most optimal stretch or deformation for the best rebound? What if 1/2 inch is good, but still not yet even taxing the system yet? What if 2 inches is too much stress on the system, beyond optimal? 6. Think about 5 for a bit. If agreed, then can you understand why I believe intuitively that in order to get the best power transfer, there is an optimal stringbed deformation that we should aim for. And that can be adjusted by string tension (and also shaft stiff/flex) according to how fast/powerful the person can swing his racket. /thought experiment
I think that there is too much arguing going on over something that probably can't be proven either way. Pure physicists would have a hard time dealing with this subject as they tend to deal more in the abstract than in real world conditions, engineers would tend to be able to apply physics to the real world better and in many cases engineers do NOT do so with the basis of science and math but on imperical data. There are too many variables including swing speed, swing technique, racket flexibility, string composition and flexibility... etc. Composition of the string has a noticeable affect on it's performance, as we all know if you compared something like BG65 to BG66. Going back to the steel analogy, a braided cable is more flexible and stronger than a single strand of equal thickness. If we're going to ignore all other aspects and focus purely on tension (keeping all other variables the same) then I will agree that there is a tension range in which you will have the maximum energy transfer but in reality it's lower than most of us want to play with as we lose controllability. Look at all models of elastic behavoir such as a trampoline, the bow (as in bow and arrow)... etc. They all depend on the transfer of energy from one object to another. There is one thing to keep in mind, the stronger the tension in the string the higher the theoretical power it can transfer if you can generate the swing speeds to still bend the strings in order to transfer that power. I make mention of the bow and arrow earlier and will use it as an example. A bow that a child or woman can bend will be more flexible than one a man can and therefore will generate less power. But if you give the bow that a man can bend to a woman then she cannot pull it back far enough to put the bow into enough tension that it has the same power as a bow designed for her. Therefore we do need to match the tension on the strings to the swing speed of the player in order to maximize the transfer of energy. Springs are another example of stored energy and come in various sizes, compositions, lengths, thicknesses... etc. just like our strings do and offer different levels of stored energy. These discussions should really center more around conservation of energy or conservation of momentum than any other types of physics theories so in that way I agree with jerby. Keep in mind that we're talking both potential and kinetic energy here (as in my spring example). This is all my opinion of course and any one is more than welcome to dispute or discuss them.
From the title of the OP's thread, we're really only considering tension and swing speed. We want to understand the relationship between the two, so obviously we have to keep all other factors exactly the same. Ceteris paribus. Obviously it would be overly complex to include other factors like string thickness/material, frame/shaft stiffness/material, ambient temperature, type of shuttle, etc. I'll let others study about them if they want to. Good point. As was mentioned by Dinkalot, we should try to play at the lowest tension that we can still tolerate in terms of controllability. Very good analogy, now why didn't I think of it! That's what I've been trying to say all along! The string tension has to be matched to the swing speed for optimal energy transfer. I was trying to show that via an optimal stringbed deformation, and the bow/arrow analogy with differing tensions for child vs. adult is very effective. I appreciate the oppurtunity for discussion. Thanx!
No hard and fast rule. Usually I keep a few rackets with different tension. A range from 22lbs to 28lbs tension. The lesser tension helps to generate power ...due to elasticity of the string. The higher tension requires hard hitting to generate the same amount of power. Usually when I get a bit tired I switched my racket to lower tension and this confuse my opponents. Suddenly my pace is different because of the string tension. Ha Ha... its fun anyway not just sticking to one tension. You can really experiment. I also used different rackets...some are heavier for training my wrist. Some are lighter. So I experiment a lot. Enjoy my game...with different opponent. I don't stick to playing with the same gang. I join a few groups in different days of the week. For those opponents who are less powerful, I usually use lower tension to save my energy and make them run around the 4 corners of the court. I can really feel the shuttle bouncing like a tennis ball. Its interesting. With higher tension, I need to use more energy directing the shuttles. I usually use it when I am very fresh and fit. When I feel tired, I use lesser tension rackets.
Don't know who put it up originally, but the bow and arrow analogy is the one that I find easiest to visualise. Let's say you have a 10 year old boy with a bow strung at 10 lbs, and a grown man with an adult bow at 30 lbs. The boy can pull his bow string back a full 3 feet and fire an arrow, and the man can do the same with the boy's bow. But when you give the boy the man's 30 lbs bow, he can only pull it back a few inches and so gets no distance at all on the arrow. But the man can pull his 30 lbs bow back the full 3 feet, so gets a LOT more distance on the arrow than he could with the boy's 10 lbs bow.
Woah... I just looked up if stringing at higher tensions (assuming you have the strength) would give you more power but I ended up reading an intense argument Soooooo..... can I sum up this thread by saying IF you have the strength, stringing higher will give you MORE power? (or am I also wrong?)
in my opinion , why professional players can string up to 30 to 32 tension , because the way of hitting the shutters and the feeling must be there, if the tension of 30 and above be there too. Professional players . they do conditioning like going to the gym do weight training on their wraist, shoulders and legs, to strengthen themselves, so playing of high tensions no problem to them ..
In general, professional player trains everyday. So, their arms are much stronger than average players. This warrants them to go for higher tension and gives them the ability to last throughout the match. For those who don't train regularly, you will be a laughing stock for using high tension. After 1 game, your arm may be deemed useless. I wonder how many consequtive back hand you can do with high tension? Skill matters too. It is more of an ego thingy to go for high tension.
It's a conspiracy. BWF told all pros to go high tension, thus we mimic them and break our string faster, so we pay for more stringing. (More money for badminton in general) /sarcasm Now that the jokes out of the way. Do not, I repeat, do not go high tension just because of your ego. I go 24lbs max(eager to go 25 soon), and most people that I know are on 27 and above. I found it especially humorous when a player weaker than me told "You should go up a few pounds, you should be good enough to handle it, since I handle those easily." I can't help but think "Why the hell you get such a high tension in the first place?" It's all ego. Just stick to the number that suits you. Just because pro's use Z-force, doesn't mean Z-force is the best racket. (From experience, I take my MP22, a cheap racket over it any day)
Professionals use high tension and thin strings (0.66mm) because it gives them better accuracy. Power comes naturally to them. Their wrists are well trained while techniques and court strategies are miles apart from us. For me, i would have stringed to 30lb if i have the money. Since i broke my precious armortec700 at the stringers, i am more cautious with the string tension. Now, i only string max 26x25lb bg66 on both sw35 and volt80. The challenge to master 30lbs it is too tempting.
imagine hulk-strength player like FuHaiFeng or Ko-sunghyun using 0.66 string @ 22 lbs.. and they're clear / lob with their full power.. probably reach the service judge Could be right and safe. But for me, not stringing highend racket with high tension is defeating the purpose of enjoying a glorious moment and sensation that I look for before buying them (apart from personal tension choice)
agree. if you can swing strong and hard, then the faster high tension string will match your speed, and produce the best synergy between you and the string, resulting in the shuttle repelling at very high speed. if you cannot string fast like many of us amateurs, then a high tension stringbed will akin to a wooden board, you are not able to stretch the strings and the shuttle will no rebound well.
