A springboard or diving board is used for

diving Diving most often refers to: * Diving (sport), the sport of jumping into deep water * Underwater diving, human activity underwater for recreational or occupational purposes Diving or Dive may also refer to: Sports * Dive (American football), a ...

and is a board that is itself a

spring Spring(s) may refer to: Common uses * Spring (season), a season of the year * Spring (device), a mechanical device that stores energy * Spring (hydrology), a natural source of water * Spring (mathematics), a geometric surface in the shape of a ...

, i.e. a linear flex-spring, of the

cantilever A cantilever is a rigid structural element that extends horizontally and is supported at only one end. Typically it extends from a flat vertical surface such as a wall, to which it must be firmly attached. Like other structural elements, a canti ...

type. Springboards are commonly fixed by a

hinge A hinge is a mechanical bearing that connects two solid objects, typically allowing only a limited angle of rotation between them. Two objects connected by an ideal hinge rotate relative to each other about a fixed axis of rotation: all other ...

at one end (so they can be flipped up when not in use), and the other end usually hangs over a

swimming pool A swimming pool, swimming bath, wading pool, paddling pool, or simply pool, is a structure designed to hold water to enable Human swimming, swimming or other leisure activities. Pools can be built into the ground (in-ground pools) or built ...

, with a point midway between the hinge and the end resting on an adjustable

fulcrum A fulcrum is the support about which a lever pivots. Fulcrum may also refer to: Companies and organizations * Fulcrum (Anglican think tank), a Church of England think tank * Fulcrum Press, a British publisher of poetry * Fulcrum Wheels, a bicy ...

Springboard materials

Modern springboards are made out of a single-piece extrusion of aircraft-grade aluminum. The Maxiflex Model B, the board used in all major competitive diving events, is made out of such aluminum, and is heat treated for a yield strength of . The slip-resistant surface of the board is created using an epoxy resin, finished with a laminate of flint silica and alumina in between the top coats of resin. This thermal-cured resin is aqua-colored to match the water of a clean pool.

Adjustment of the spring constant

The

spring constant In physics, Hooke's law is an empirical law which states that the force () needed to extend or compress a spring (device), spring by some distance () Proportionality (mathematics)#Direct_proportionality, scales linearly with respect to that ...

of a springboard is usually adjusted by way of a fulcrum that is located approximately mid way along the springboard. Springboards are usually operated in a linear regime where they approximately obey

Hooke's law In physics, Hooke's law is an empirical law which states that the force () needed to extend or compress a spring (device), spring by some distance () Proportionality (mathematics)#Direct_proportionality, scales linearly with respect to that ...

. When loaded with a diver, the combination of the diver's approximately constant

mass Mass is an intrinsic property of a body. It was traditionally believed to be related to the quantity of matter in a physical body, until the discovery of the atom and particle physics. It was found that different atoms and different elementar ...

, and the constant

stiffness Stiffness is the extent to which an object resists deformation in response to an applied force. The complementary concept is flexibility or pliability: the more flexible an object is, the less stiff it is. Calculations The stiffness, k, of a b ...

of the spring(board) result in a

resonance frequency Resonance describes the phenomenon of increased amplitude that occurs when the frequency of an applied periodic force (or a Fourier component of it) is equal or close to a natural frequency of the system on which it acts. When an oscillat ...

that is adjustable by way of the spring constant (set by the fulcrum position). Since the resulting system is in an approximately linear regime, it may be modeled fairly accurately by a second order

differential equation In mathematics, a differential equation is an equation that relates one or more unknown functions and their derivatives. In applications, the functions generally represent physical quantities, the derivatives represent their rates of change, an ...

. Typically the resonance frequency can be adjusted over a range of a 2:1 or 3:1

ratio In mathematics, a ratio shows how many times one number contains another. For example, if there are eight oranges and six lemons in a bowl of fruit, then the ratio of oranges to lemons is eight to six (that is, 8:6, which is equivalent to the ...

.The Physics of Springboard and Platform Diving
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Adjusting the fulcrum

The fulcrum on competitive diving boards travels over a range of , and is set by way of a foot wheel that is approximately in

diameter In geometry, a diameter of a circle is any straight line segment that passes through the center of the circle and whose endpoints lie on the circle. It can also be defined as the longest chord of the circle. Both definitions are also valid for ...

.Duraflex International/Coach woody Franklyn: diving board construction
To stiffen the spring (as if tightening it), the foot wheel is usually turned counter clockwise. Some may find this counter intuitive, since usually things are tightened by turning clockwise. However, with a little experience, people realize the fulcrum moves in the direction the bottom of the foot faces when placed on the foot wheel. :Note – Standing behind or in front of the knob, rather than directly above it, will provide better

lever A lever is a simple machine consisting of a beam or rigid rod pivoted at a fixed hinge, or ''fulcrum''. A lever is a rigid body capable of rotating on a point on itself. On the basis of the locations of fulcrum, load and effort, the lever is div ...

age to move the fulcrum. This is accomplished by holding on to the hand rails and leaning the body a few degrees, then placing the foot as low as possible on the knob. In this way, it is possible to move even the most difficult fulcrum.

Heights of springboards

Springboards are usually located either above the water surface. It is very seldom that one is mounted at a height other than these two standard heights.

Historical heights of springboards

Before around 1960, springboards, usually made of wood, were located at heights of either , or above the water. American artist

Norman Rockwell Norman Percevel Rockwell (February 3, 1894 – November 8, 1978) was an American painter and illustrator. His works have a broad popular appeal in the United States for their reflection of Culture of the United States, the country's culture. Roc ...

's painting titled ''Boy on High Dive'' (1947) shows a boy (Rockwel's youngest son, Peter) peering over a typical wooden springboard of the early 20th century era at the 20 feet height.

Home springboards

After an incident in

Washington Washington commonly refers to: * Washington (state), United States * Washington, D.C., the capital of the United States ** A metonym for the federal government of the United States ** Washington metropolitan area, the metropolitan area centered o ...

in 1993, most US and other pool builders are reluctant to equip a residential

with a diving springboard so home diving pools are much less common these days. In the incident, 14-year-old Shawn Meneely made a "suicide dive" (holding his hands at his sides, so that his head hit the bottom first) in a private swimming pool and was seriously injured and became a

tetraplegic Tetraplegia, also known as quadriplegia, is defined as the dysfunction or loss of motor and/or sensory function in the cervical area of the spinal cord. A loss of motor function can present as either weakness or paralysis leading to partial or ...

. The lawyers for the family, Jan Eric Peterson and Fred Zeder, successfully sued the diving board manufacturer, the pool builder, and the National Spa and Pool Institute (NSPI) over the inappropriate depth of the pool. The NSPI had specified a minimum depth of which proved to be insufficient in the above case. The pool into which Meneely dived was not constructed to the published standards. The standards had changed after the diving board was installed on the non-compliant pool by the homeowner. But the courts held that the pool "was close enough" to the standards to hold NSPI liable. The multimillion-dollar lawsuit was eventually resolved in 2001 for US$6.6 million ($8 million after interest was added) in favor of the plaintiff.Appeals Court State of WA, Docket Number:18036-1-III Title: Shawn Meneely, et al. v. S. R. Smith, Inc., et al. The NSPI was held to be liable, and was financially strained by the case. It filed twice for

Chapter 11 Chapter 11 of the United States Bankruptcy Code (Title 11 of the United States Code) permits reorganization under the bankruptcy laws of the United States. Such reorganization, known as Chapter 11 bankruptcy, is available to every business, wheth ...

bankruptcy protection and was successfully reorganized into a new swimming pool industry association.

References

{{Authority control Diving (sport) Springs (mechanical)