WO2022140062A1 - Adjustable stiffness mattress systems and related methods - Google Patents

Abstract

Body support systems (10) are provided including: at least one cushion layer (20) defining a length, width, thickness, top side, bottom side, lateral sides, and longitudinal sides; at least one outer cover layer (28) overlying the at least one cushion layer (20), comprising a top portion that extends over the top side, lateral border portions that extend over the lateral sides, and longitudinal border portions that extend over the longitudinal sides; and a plurality of super-coiled heat-actuating actuators (24) extending along at least one of the lateral border portions or the longitudinal border portions in the thickness direction, the super-coiled heat-actuating actuators (24) comprising a twisted and coiled elongate member (18) and a resistive heating element (19) configured to selectively heat the elongate member (18) and configured to selectively vary their lengths to variably compress the at least one cushion layer (20) in the thickness direction, to vary the stiffness of the at least one cushion layer (20).

Description

ADJUSTABLE STIFFNESS MATTRESS SYSTEMS AND RELATED METHODS

CROSS-REFERENCE TO RELATED APPLICATION

[001] The application claims priority benefit of U.S. Provisional Patent Application No.

63/130,057, filed on December 23, 2020, and entitled Adjustable Stiffness Mattress Systems and Related Methods, the entire content of which is hereby expressly incorporated herein by reference in its entirety.

FIELD OF THE DISCLOSURE

[002] The present disclosure generally relates to body support systems (e.g., cushions and mattresses) having adjustable stiffness/firmness of portions thereof, and more specifically to body support systems that include a cover layer that adjusts its configuration to adjust the stiffness/firmness of at least one foam layer beneath the cover layer.

BACKGROUND

[003] Sleep plays an important role in a person’s overall health and enjoyment of life. The quality and quantity of sleep affect the body’s ability to function normally and the ability to reach peak performance. Physiologically, sleep affects brain activity, heart rate, blood flow, body temperature and other physiological parameters. Sleep deprivation shows a strong correlation to obesity, diabetes, stroke, depression, and hypertension.

[004] Restful sleep is at least partially dependent upon the level of comfort of an individual while lying prone on a mattress. Concentration of pressure on certain parts of the body and/or poor skeletal alignment are been linked to restless sleep. Sleeping on a mattress or other support surface that does not properly support and conform to the shape of a particular user’s body or to curve of the particular user’s spine can significantly contribute to restlessness or inability to sleep.

[005] Traditionally sleep systems incorporate a mattress consisting of an outer layer of fabric and padding, surrounded by a series of spring coils. The fabric is stretched tightly across the padding to hold them in place, which in many eases creates a surface that is too hard.

The mattress is usually supported by a flexible box spring, thereby enabling the mattress to compress where needed. However, the stiffness of the box spring can cause it to push back against the mattress in areas of greatest compression.

[006] More recently, foam mattresses have been developed to provide adequate support without the use of spring coils. Current foam technology can be categorized according to load bearing capacity by time and temperature variables. Rates of recovery and thermal response rates of foam samples are also measured. Although conventional foam mattresses provide the advantage of shape conformity and thermal responsiveness, structural support is sacrificed, particularly in areas of highest load concentrations. Although changing the stiffness/firmness of a foam mattress can alleviate this problem to some degree, the optimal stiffness should be different depending on body type/shape/configuration and weight, for example. Bedding manufacturers tend to ignore body types and weight, and market sleep systems constructed under an inaccurate assumption that 95% of the population has the same body metrics. Further, personal preferences as to the stiffness/firmness and support of matters that is most comfortable differ from individual to individual, even within the same body types.

[007] Accordingly, what is needed is an improved body support system (e.g., cushions and mattresses) that can be selectively optimized to provide the desired structural support for an individual’s body configuration and preferences. Moreover, what is needed in the industry is a body support system, in which the stiffness/firmness can be selectively adjusted repeatedly, and without a significant manufacturing cost.

[008] Therefore, there is still a need for body support systems, and in particular mattress systems, with adjustable stiffness/firmness, and potentially support, which eliminates the problems discussed above.

[009] While certain aspects of conventional technologies have been discussed to facilitate disclosure of the invention, Applicants in no way disclaim these technical aspects, and it is contemplated that the claimed invention may encompass one or more of the conventional technical aspects discussed herein.

[0010] In this specification, where a document, act or item of knowledge is referred to or discussed, this reference or discussion is not an admission that the document, act or item of knowledge or any combination thereof was, at the priority date, publicly available, known to the public, part of common general knowledge, or otherwise constitutes prior art under the applicable statutory provisions; or is known to be relevant to an attempt to solve any problem with which this specification is concerned.

SUMMARY OF THE DISCLOSURE

[0011] Briefly, the present inventions satisfy the need for improved body support systems/devices with portions or zones that can be selectively (and repeatedly) optimized to provide a desired comfort (e.g., stiffness/firmness) and/or support for an individual according to their physiological needs and/or desires, without a significant increase in manufacturing costs that would normally be associated with such systems/devices.

[0012] Certain embodiments of the presently-disclosed adjustable stiffness/firmness body support (e.g., mattress and cushion) systems, and methods for making and using the adjustable stiffness/firmness body support systems and components thereof, have several features, no single one of which is solely responsible for their desirable attributes. Without limiting the scope of the adjustable stiffness/firmness body support systems and methods as defined by the claims that follow, their more prominent features will now be discussed briefly. After considering this discussion, and particularly after reading the section of this specification entitled “Detailed Description,” one will understand how the features of the various embodiments disclosed herein provide a number of advantages over the current state of the art.

[0013] One embodiment of the present disclosure provides an adjustable stiffness/firmness body support (e.g., cushion or mattress) system configured such that the stiffness/firmness thereof can be selectively varied or optimized to provide a desired stiffness/firmness (and potentially structural support) for a user’s preference (regardless of their body type and weight).

The adjustable stiffness body support system includes at least one cushioning layer, such as a foam layer, and a plurality of controllable super-coiled heat-actuating actuators (e.g., supercoiled polymer actuators) that are coupled to portions of a cover layer that at least partially surrounds the at least one cushion layer. The super-coiled heat-actuating actuators are configured to selectively vary in length such that they control the length or thickness of the portions of the cover layer to change/adjust/vary the thickness of the cushioning layer. The super-coiled heat-actuating actuators may be coupled to border or side portions of the cover layer extending along the thickness of the at least one cushioning layer. The adjustment of the lengths of the super-coiled heat-actuating actuators may control/change the amount that the border portions are stretched (or otherwise vary their length) to vary the degree to which the cover layer compresses or constrains the at least one cushioning layer in the thickness direction. As such, as the super-coiled heat-actuating actuators selectively lengthen/shorten in the thickness direction, and the at least one cushioning layer thereby becomes more/less compressed. As the compression of the at least one cushioning layer varies, the stiffness/firmness thereof varies. Since the super-coiled heat-actuating actuators are selectively controllable, the system provides for selectively controllable adjustable stiffness/firmness of the body support system.

[0014] In one aspect, the present disclosure provides an adjustable stiffness body support system, comprising: at least one cushion layer comprising at least one foam layer and defining a length, a width, a thickness, a top side, a bottom side, lateral sides that extend between the top and bottom sides, and longitudinal sides that extend between the top and bottom sides and are positioned between the lateral sides; at least one outer cover layer overlying the at least one cushion layer, comprising a top portion that extends over the top side of the at least one cushion layer, lateral border portions that extend over the lateral sides of the at least one cushion layer, and longitudinal border portions that extend over the longitudinal sides of the at least one cushion layer; and a plurality of super-coiled heat-actuating actuators extending along at least one of the lateral border portions and the longitudinal border portions of the at least one outer cover layer in the thickness direction, the super-coiled heat-actuating actuators comprising a twisted and coiled elongate member and a resistive heating element configured to selectively heat the elongate member. The elongate member comprises anisotropic thermal expansion such that they include a length-direction thermal expansion coefficient that is greater than their cross-sectional thermal expansion coefficient. The super-coiled heat-actuating actuators are configured to selectively and reversibly vary their lengths to variably lengthen and shorten the lateral border portions and/or the longitudinal border portions along the thickness direction, and thereby variably compress the at least one cushion layer in the thickness direction, to vary the stiffness of the at least one cushion layer. [0015] In some embodiments, the elongate member comprises a substantially circular crosssection, and wherein the cross-sectional thermal expansion coefficient of the elongate member comprises a radial thermal expansion coefficient.

[0016] In some embodiments, the plurality of super-coiled heat-actuating actuators are arranged along the lateral border portions and the longitudinal border portions. In some embodiments, at least three super-coiled heat-actuating actuators are associated with the lateral border portions.

In some embodiments, at least three super-coiled heat-actuating actuators are associated with the longitudinal border portions.

[0017] In some embodiments, portions of the super-coiled heat-actuating actuators are coupled to the lateral border portions. In some embodiments, portions of the super-coiled heat-actuating actuators are coupled to the longitudinal border portions. In some embodiments, an end portion of the super-coiled heat-actuating actuators is coupled to the top portion of the at least one cover layer. In some embodiments, an end portion of the super-coiled heat-actuating actuators is coupled to the bottom portion of the at least one cover layer.

[0018] In some embodiments, the at least one foam layer comprises at least one polyurethane foam. In some embodiments, the at least one foam layer comprises viscoelastic foam.

[0019] In some embodiments, the system further comprises a frame structure positioned below the at least one cushion layer, the frame structure physically supporting the at least one cushion layer. In some embodiments, an end portion of the plurality of super-coiled heat-actuating actuators is coupled to the frame structure. In some embodiments, the outer cover layer extends about the frame structure.

[0020] In some embodiments, the outer cover layer extends about the at least one cushion layer and the plurality of super-coiled heat-actuating actuators. In some embodiments, the outer cover layer comprises a fabric layer. In some embodiments, the outer cover layer comprises a fire sock. In some embodiments, the resistive heating element comprises a material that increases in temperature when a voltage is applied thereacross. In some embodiments, the resistive heating element is configured to heat the elongate member via a process of Joule heating. In some embodiments, the resistive heating element comprises a resistive metal material.

[0021] In some embodiments, the resistive heating element is wrapped around the cross-section of the elongate member. In some embodiments, the resistive heating element is wrapped around the coils of the elongate member. In some embodiments, the resistive heating element extends adjacent to the elongate member. In some embodiments, the resistive heating element comprises a coating on the elongate members. In some embodiments, the resistive heating element comprises a portion of the elongate members.

[0022] In some embodiments, the elongate members of the plurality of super-coiled heatactuating actuators are configured such that they shorten in length when heated. In some embodiments, the elongate members of the plurality of super-coiled heat-actuating actuators are configured such that they increase in length when heated.

[0023] In some embodiments, the elongate members of the plurality of super-coiled heatactuating actuators are configured such that they at least partially reversibly untwist as the temperature thereof increases. In some embodiments, the elongate members of the plurality of super-coiled heat-actuating actuators comprise at least one precursor fiber that has components substantial internal alignment of its composition along the length direction.

[0024] In some embodiments, the elongate members of the plurality of super-coiled heatactuating actuators comprise yarn. In some embodiments, the elongate members of the plurality of super-coiled heat-actuating actuators comprise filaments. In some embodiments, the elongate members of the plurality of super-coiled heat-actuating actuators comprise polymer yarn or filaments. In some embodiments, the elongate members of the plurality of super-coiled heatactuating actuators comprise nylon yarn or filaments. In some embodiments, the elongate members of the plurality of super-coiled heat-actuating actuators comprise yarn or filaments. In some embodiments, the elongate members are pre-stretched to substantially align macromolecules thereof along the length of the elongate members.

[0025] In some embodiments, the elongate members are configured to reversibly decrease in length by at least 4% decrease when heated to 110 °C. In some embodiments, the elongate members are configured such that the super-coiled heat-actuating actuators reversibly vary in length along the thickness direction by at least 30% decrease when the temperature thereof is varied by at 30 degrees F.

[0026] In some embodiments, the twisted nature of the elongate members arranges the constituent elements of the elongate members in helices. In some embodiments, the constituent elements comprise polymer chains. In some embodiments, the elongate members of the plurality of super-coiled heat-actuating actuators comprise carbon yams with bundles of nanotubes oriented along the length of the elongate members.

[0027] In some embodiments, the elongate members of the plurality of super-coiled heatactuating actuators comprise wax-filled yams made from niobium nanowires and/or graphene- oxide fibers. In some embodiments, the elongate members of the plurality of super-coiled heatactuating actuators comprise polymer nanofiber yarns. In some embodiments, the elongate members of the plurality of super-coiled heat-actuating actuators comprise electrospun fibers of piezoelectric poly(vinylidene fluoride trifluoroethylene) (PVDF-TrFE). [0028] In some embodiments, the super-coiled heat-actuating actuators are configured to provide specific work during contraction thereof of at least 2 kJ/kg.

[0029] In some embodiments, the system further comprises a control unit that is configured to selectively control actuation of the super-coiled heat-actuating actuators and, thereby, the thickness of the lateral and/or longitudinal border portions to adjust the compression of the at least one cushion layer, and, thereby, the stiffnesses thereof. In some embodiments, the control unit is configured to be manually operable by a user. In some embodiments, the control unit comprises a remote control device that is configured to be manually operable by a user and control the control unit. In some embodiments, the remote control device is configured to wirelessly communicate with the control unit. In some embodiments, the remote control device and the control unit are coupled via at least one electrical communication wire.

[0030] In some embodiments, the control unit comprises a plurality of predetermined selectable stiffness profiles that comprise differing lengths of the super-coiled heat-actuating actuators and, thereby, differing stiffnesses and/or differing stiffness distributions of the at least one cushion layer. In some embodiments, the predetermined selectable stiffness profiles comprise differing stiffness distributions corresponding to identified lying positions of a user. In some embodiments, the identified lying positions comprise at least three lying positions corresponding to the positions of the user lying on their back, on their stomach and on their side. In some embodiments, the control unit comprises one or more visual indicator that indicates the relative stiffness of at least one portion of the at least one cushion layer.

[0031] In some embodiments, the stiffness of at least a portion of the at least one cushion layer can be selectively varied via the super-coiled heat-actuating actuators between about 5 lbs at 25% IFD to about 120 lbs at 25% IFD. In some embodiments, the stiffness of at least a portion of the at least one cushion layer can be selectively varied via the super-coiled heat-actuating actuators between about 10 lbs at 25% IFD to about 100 lbs at 25% IFD. In some embodiments, the stiffness of at least a portion of the at least one cushion layer can be selectively varied via the super-coiled heat-actuating actuators between about 10 lbs at 25% IFD to about 75 lbs at 25% IFD. In some embodiments, the stiffness of at least a portion of the at least one cushion layer can be selectively varied via the super-coiled heat-actuating actuators between about 10 lbs at 25% IFD to about 50 lbs at 25% IFD.

[0032] In some embodiments, the stiffness of at least a portion of the at least one cushion layer can be selectively varied via the super-coiled heat-actuating actuators between a stiffness range that provides for about Yi inch to about 3 inches of deflection of the at least one cushion layer when the user is supported thereby.

[0033] In some embodiments, the system is configured as a mattress system. In some embodiments, the system is configured as a cushion system.

[0034] In another aspect, the present disclosure provides a method for adjusting the firmness of a body support system. The method comprises providing or obtaining the body support system as described above; and selectively varying the length of the super-coiled heat-actuating actuators along the thickness direction via utilizing the resistive heating elements to vary the temperature of the actuators to variably compress the at least one cushion layer and adjust the stiffnesses thereof.

[0035] These and other features and advantages of the disclosure and inventions will become apparent from the following detailed description of the various aspects of the invention taken in conjunction with the appended claims and the accompanying drawings. The summary above is not intended to describe each illustrated embodiment or every implementation of the present disclosure. The figures and the detailed description that follow more particularly exemplify these embodiments.

BRIEF DESCRIPTION OF THE DRAWINGS

[0036] The subject matter, which is regarded as the invention(s), is particularly pointed out and distinctly claimed in the claims at the conclusion of the specification. The foregoing and other features, aspects, and advantages of the disclosure will be readily understood from the following detailed description taken in conjunction with the accompanying drawings, which are not necessarily drawn to scale, wherein:

[0037] FIG. 1 illustrates an elevational perspective view depicting an adjustable stiffness/firmness body support system in accordance with an embodiment of the disclosure. [0038] FIG. 2 illustrates a side cross-sectional view of the adjustable stiffness/firmness body support system of FIG. 1 in accordance with an embodiment of the disclosure.

[0039] FIG. 3 illustrates a side view of a super-coiled heat-actuating actuator of the adjustable stiffness/firmness body support system of FIG. 1 in accordance with an embodiment of the disclosure.

[0040] FIG. 4 illustrates an enlarged side view of a portion of the super-coiled heat-actuating actuator of FIG. 3 in accordance with an embodiment of the disclosure.

[0041] FIG. 5 illustrates a side view of another super-coiled heat-actuating actuator in accordance with an embodiment of the disclosure.

[0042] FIGS. 6A, 6B and 6C illustrate side views of the portion of the super-coiled heatactuating actuator of FIG. 4 during heat-driven actuation in accordance with an embodiment of the disclosure. [0043] FIG. 7 illustrates an elevational perspective view of a portion of a border portion of the adjustable stiffness/firmness body support system of FIG. 1 with a plurality of the super-coiled heat-actuating actuators incorporated therein in accordance with an embodiment of the disclosure.

[0044] FIG. 8A illustrates a side view of a portion of the border portion, and an enlarged view of a super-coiled heat-actuating actuator thereof, of the adjustable stiffness/firmness body support system of FIG. 1 when not heat actuated, in accordance with an embodiment of the disclosure. [0045] FIG. 8B illustrates a side view of the portion of the border portion, and an enlarged view of a super-coiled heat-actuating actuator thereof, of the adjustable stiffness/firmness body support system of FIG. 1 when heat actuated, in accordance with an embodiment of the disclosure.

[0046] FIG. 9A illustrates a side cross-sectional view of the adjustable stiffness/firmness body support system of FIG. 1 when the super-coiled heat-actuating actuators thereof are not heat actuated.

[0047] FIG. 9B illustrates a side cross-sectional view of the adjustable stiffness/firmness body support system of FIG. 1 when the super-coiled heat-actuating actuators thereof are heat actuated.

[0048] While embodiments of the disclosure are amenable to various modifications and alternative forms, specifics thereof are shown by way of example in the drawings and will be described in detail. It should be understood, however, that the intention is not to limit the disclosure to the particular embodiments described. On the contrary, the intention is to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the disclosure as defined by the appended claims. DETAILED DESCRIPTION

[0049] Aspects of the present disclosure and certain features, advantages, and details thereof, are explained more fully below with reference to the non-limiting embodiments illustrated in the accompanying drawings. Descriptions of well-known materials, fabrication tools, processing techniques, etc., are omitted so as to not unnecessarily obscure the details of the inventions. It should be understood, however, that the detailed description and the specific example(s), while indicating embodiments of inventions of the present disclosure, are given by way of illustration only, and are not by way of limitation. Various substitutions, modifications, additions and/or arrangements within the spirit and/or scope of the underlying inventive concepts will be apparent to those skilled in the art from this disclosure.

[0050] Approximating language, as used herein throughout the disclosure, may be applied to modify any quantitative representation that could permissibly vary without resulting in a change in the basic function to which it is related. Accordingly, a value modified by a term or terms, such as “about” or “substantially,” is not limited to the precise value specified. For example, these terms can refer to less than or equal to 5% and greater than or equal to -5%, such as less than or equal to 2% and greater than or equal to -2%, such as less than or equal to 1% and greater than or equal to -1%, such as less than or equal to 0.5% and greater than or equal to -0.5%, such as less than or equal to 0.2% and greater than or equal to -0.2%, such as less than or equal to 0.1% and greater than or equal to -0.1%, such as less than or equal to 0.05% and greater than or equal to -0.05%. In some instances, the approximating language may correspond to the precision of an instrument for measuring the value.

[0051] The term “user” is used herein to refer to a mammal (e.g., human or animal, such as a pet or livestock) that utilizes the adjustable stiffness/firmness body support systems disclosed herein to physically support at least a portion themselves. For example, a user may sit or lay on a top or upper surface or portion of the adjustable stiffness/firmness body support systems disclosed herein so that at least a portion of the user’s body weight is physically supported by the system. [0052] The terms “stiffness” and “firmness” (also referred to as “plushness”) are used synonymously herein to refer to the body support system’s comfort on initial touch by a user, or how soft or firm the system feels to the user. Stiffness/firmness refers to the comfort feel of a body support system and how hard or soft it is, such as how much a user “sinks” in, is “cradled” by, or deflects the system during use. Stiffness/firmness is a subjective quality of a body support system, such as a mattress or cushion. Stiffness/firmness is a way of describing the feel of a body support system specifically in terms of comfort. Being supported (e.g., laying or sitting) on concrete would be one extreme level of firmness, while an opposite extreme would be like floating on a cloud. Firmness is often described as being very subjective because what may feel comfortable to one user can be uncomfortable to another user. Firmness, essentially, is a subjective measure of how soft or hard a body support system feels to a user when the user is supported thereby (e.g., sits or lays down on the body support system).

[0053] How a particular body support system feels, with respect to stiffness/firmness, to a user is typically dictated by the user’s height, weight, gender, preferred/usual sleeping position(s), and personal preference. The stiffness/firmness of a body support system is critical to a comfortable feeling during use by a user. For this reason, it is common to see body support systems offered in a number of different firmness levels to allow users to find a model that will suit their preferences. As described further below, the body support systems disclosed herein allow or provide for adjustable stiffnesses and stiffness profiles that are user selectable and variable. [0054] Body support systems, such as mattresses and cushions, are often generally categorized with respect to their firmness. For example, terms like “extra firm,” “medium-firm,” “plush,” and others may be used to describe the firmness of body support systems. As another example, some refer to a firmness scale of body support systems. Such a scale may include: a #1 firmness or “extremely soft/plush” designation to refer to a body support system with a maximum softness with lots of sink; a #2-#3 or “soft” designation to refer to quite soft and plush designation to refer to a body support system with definite sink and a significant amount of hug and sinkage, such as in the about 1.5-3 inch range; a #4-#6 or “medium” designation to refer to a body support system with a common firmness level that offers a middle-ground with some plushness but more limited sink, such as sinkage and hug in the about 1-2 inch range; a #7-#9 or “firm” designation to refer to a body support system with much harder mattress with limited softness and sinkage or hug, such as in the range of about 1 inch or less; and #10 or “extremely firm” designation to refer to a body support system with no softness, plushness or sink. The body support systems of the present disclosure provide for adjustable stiffness body support systems that can be selectively vary to any one of such firmness/stiffness.

[0055] While the disclosed body support systems are configured to vary in firmness/stiffness, it is noted that firmness/stiffness may impact other qualities of the systems, such as airflow, temperature, contouring properties, support, durability and odor. For example, firmness is not the same as “support.” The term “support” refers to how well a body support system promotes spinal or anatomical alignment when a user is being supported by the system. A body support system that offers pressure point relief and keeps the spine in a proper position during use, for example, is supportive regardless of how hard or soft that body support system is (i.e., how firm the body support system is). While firmness can be highly subjective, support is not. Firmness typically describes the uppermost layer(s) of a body support system that determine the system’s comfort levels, while support typically describes the core and lower layers of the system that determine how the system encourages proper spinal/anatomical alignment and relieve pressure.

[0056] As another example, although the firmness and the density of body support systems are often fairly closely linked, they may not be identical. Density is an objective measurement of pounds per cubic foot. Generally speaking though, denser body support systems tend to be a little firmer systems.

[0057] One metric that is utilized to attempt to define or standardized a measurement for the firmness/stiffness of body support systems, such as mattresses and cushion systems, is Indentation Load Deflection (ILD)/Indentation Force Deflection (IFD). ILD is a measurement in the firmness level of a body support system. The higher the number, the firmer it is and vice versa for lower numbers.

[0058] ILD is a value that represents the force needed to compress natural latex, polyurethane and several other types of foam that are often utilized in body support systems. ILD is used across many body support system industries, such as with mattress, car seat and furniture body support systems. The ILD measurement value is given to an individual layer of foam within a body support system and not the entire finished system. As such, an ILD measurement may provide a general firmness rating like soft, medium or firm to a body support system, the individual foam layer(s) within the system will have their own ILD rating.

[0059] ILD is a unit of measurement that references the number of pounds (lbs) of pressure or force that is needed to indent a foam of a depth of 4” by 25%. The rating is referred to as the ILD rating or the 25% ILD rating. When measuring ILD, a foam sample of material measuring 15 inches x 15 inches x 4 inches is used. A 50 square inch circular indenter is used to compress the material to a total of 25 percent of its thickness. Normally, the firmness of foam layer(s) within body support system foams (e.g., viscoelastic memory foam layers) can range from supersoft (less than 10 lbs. @ 25% IFD) to semi-rigid (as high as 120 lbs. @ 25% IFD).

[0060] While IFD is useful to provide a metric to gauge the firmness/stiffness of a body support system, it does have some limitations. For example, ILD only measures the firmness of one or more foam layers in a body support system and not any of the other layers’ firmness. Further, ILD of a layer can vary in response to things like humidity and heat.

[0061] The disclosed adjustable stiffness body support systems may be configured as or form a bedding system, device or product (or a portion thereof), such as a mattress, mattress cartridge, mattress topper, mattress cover, mattress protector, mattress pad or liner, mattress component, mattress accessory, pillow or the like. The disclosed adjustable stiffness body support systems may also be configured as or form a pad or mat (or a portion thereof). The disclosed adjustable stiffness body support systems may also be configured as or form a non-bedding body support cushion, such as a furniture cushion, automobile/plane/boat seat, child carrier, neck support, leg spacer, pet accessory (e.g., pet bed, pet carrier insert and other pet apparel), exercise equipment cushion or any other cushion configured to support at least a portion of a user (or a portion thereof).

[0062] As shown in FIG. 1 and 3, an exemplary adjustable stiffness body support system 10 according to the present disclosure may define a width W, length L and thickness T dimensions/directions. The system 10 may include a plurality of layers 12 that define an upper or top surface or side 14, and a lower or bottom surface or side 16, that are spaced along the thickness T dimension. In use, a user rests on the top side 14 of the system 10, and is physically supported (at least in part) by the plurality of layers 12. For example, a user may lay down or sit down on the top side 14 of the system 10, and the plurality of layers 12 may transfer the applied weight of the user to the bottom side 16. It is noted that in use, one or more additional layers or members may be positioned over the top side 14 such that the user does not directly contact the top side 14 and/or under the bottom side 16 such that the bottom side 16 does not directly contact a ground or support surface.

[0063] As shown in FIG. 1, the adjustable stiffness body support system 10 may include a plurality of super-coiled heat-actuating/heat-activating (SCHA) actuators 24 that adjust in length to adjust the stiffness/firmness of the cushion layer 20. The SCHA actuators 24 are configured to be controlled, varied, adjusted or selected by a user. In some embodiments, the system 10 may include or define a plurality of the SCHA actuators 24 arranged or extending across the width W dimension of the system 10. For example, the system 10 may include at least two adjustable SCHA actuators 24 arranged along the width W of the system 10, at least three adjustable SCHA actuators 24 arranged along the width W of the system 10, at least four adjustable SCHA actuators 24 arranged along the width W of the system 10, at least six adjustable SCHA actuators 24 arranged along the width W of the system 10, at least seven adjustable SCHA actuators 24 arranged along the width W of the system 10, or at least eight adjustable SCHA actuators 24 arranged along the width W of the system 10.

[0064] However, the system 10 may include any number of adjustable SCHA actuators 24 arranged along the width W of the system 10. In some embodiments, the system 10 may not include any of the adjustable SCHA actuators 24 arranged along the width W of the system 10 (i.e., the width W of the system 10 may be void of the adjustable SCHA actuators 24). [0065] The adjustable SCHA actuators 24 may or may not be present or positioned in the width W direction of the system 10. For example, as shown FIGS. 1 and 2, the adjustable SCHA actuators 24 may extend in the thickness direction T on/along/at at least a portion of one or more lateral border, side or peripheral portions 22 of the system 10 that form or extend along the width W of the system 10, as shown in FIGS. 1 and 2. If the adjustable SCHA actuators 24 are present along/at the width W of the system 10, they may be arranged along the width W direction in any pattern or arrangement. For example, the adjustable SCHA actuators 24 may or may not be contiguous or immediately adjacent to each other along the width W direction (e.g., they may be immediately adjacent each other or spaced out along the width W direction). As another example, the adjustable SCHA actuators 24 may be spaced or arranged along the width W direction in a uniform or non-uniform pattern/spacing.

[0066] In some embodiments, the width W of the system 10 may include a plurality of adjustable SCHA actuators 24 at/on/along at least one of the lateral border portions 22 that define or extend along the width W of the system 10 and define the longitudinal sides/ends of the system 10 along the length L direction. In some embodiments, as shown in FIGS. 1 and 2, the width W of the system 10 may include a plurality of adjustable SCHA actuators 24 at/on/along both of the lateral border portions 22 that define or extend along the widths W of the system 10. In some embodiments, the widths W of the system 10 may each include a plurality of adjustable SCHA actuators 24 that includes at least one adjustable SCHA actuator 24 proximate to one longitudinal end of the system 10 along the length L direction, at least one adjustable SCHA actuator 24 proximate to the other longitudinal end of the system 10 along the length L direction, and at least one adjustable SCHA actuator 24 positioned between or medially to the adjustable SCHA actuators 24 proximate to the longitudinal ends along the length L direction. In some alternative embodiments (not shown), one or both of the widths W of the system 10 (e.g., one or both of the lateral border portions 22) may not include any of the adjustable SCHA actuators 24 (i.e., be void of the adjustable SCHA actuators 24).

[0067] As also shown in FIGS. 1 and 2, in some embodiments, the adjustable SCHA actuators 24 may or may not be present or positioned along in the length L direction of the system 10. For example, as shown FIGS. 1 and 2, the adjustable SCHA actuators 24 may extend in the thickness direction T on/along/at at least a portion of one or more longitudinal border, side or peripheral portions 23 of the system 10 that form or extend along the length L of the system 10, as shown in FIGS. 1 and 2. If the adjustable SCHA actuators 24 are present along/at the length L of the system 10, they may be arranged along the length L direction in any pattern or arrangement. For example, the adjustable SCHA actuators 24 may or may not be contiguous or immediately adjacent to each other along the length L direction (e.g., they may be immediately adjacent to each other or spaced out along the length L direction). As another example, the adjustable SCHA actuators 24 may be spaced or arranged along the length L direction in a uniform or non- uniform pattem/spacing.

[0068] In some embodiments, the length L of the system 10 may include a plurality of adjustable SCHA actuators 24 at/on/along at least one of the longitudinal border portions 23 that define or extend along the length L of the system 10 and define the lateral sides/ends of the system 10 along the width W direction. In some embodiments, as shown in FIGS. 1 and 2, the length L of the system 10 may include a plurality of adjustable SCHA actuators 24 at/on/along both of the longitudinal border portions 23 that define or extend along the lengths L of the system 10. In some embodiments, the lengths L of the system 10 may each include a plurality of adjustable SCHA actuators 24 that includes at least one adjustable SCHA actuator 24 proximate to one lateral end of the system 10 along the length L direction, at least one adjustable SCHA actuator 24 proximate to the other lateral end of the system 10 along the length L direction, and at least one adjustable SCHA actuator 24 positioned between or medially to the adjustable SCHA actuators 24 proximate to the lateral ends along the length L direction. In some alternative embodiments (not shown), one or both of the lengths L of the system 10 (e.g., one or both of the longitudinal border portions 23) may not include any of the adjustable SCHA actuators 24 (i.e., be void of the adjustable SCHA actuators 24).

[0069] The relative arrangement of the adjustable SCHA actuators 24 also may vary. For example, as shown in FIGS. 1 and 2, the adjustable SCHA actuators 24 may be arranged in columns extending along the length L direction, and rows extending along the width W direction. However, the system 10 can include any differing layout, pattern or arrangement of the adjustable SCHA actuators 24 across the length L and width W of the system 10. For example, the adjustable SCHA actuators 24 may be substantially aligned with each other along the lateral border portions 22 in the width W direction, or offset with each other along the lateral border portions 22 in the width W direction. As another example, the adjustable SCHA actuators 24 may be substantially aligned with each other along the longitudinal border portions 23 in the length L direction, or offset with each other along the longitudinal border portions 23 in the length L direction.

[0070] As shown in FIGS. 1, 2, 8B and 9B, the plurality of layers 12 of the system 10 includes at an outer cover layer 28 and at least one cushion layer 20 positioned underneath or within the outer cover layer 28. It is noted that the at least one cushion layer 20 may include other layers in addition to the at least one cushion layer 20. For example, the at least one cushion layer 20 may include at least one additional cushioning layer, such as a protective (e.g., fire and/or moisture resistant), batting, foam, fiber, fill, gel/water, fabric or any other layer underlying (and/or overlying) the cover layer 28 and/or the at least one cushion layer 20. As another example, the outer cover layer 28 and/or the at least one cushion layer 20 may include a fire sock or fire resistive layer.

[0071] The outer cover layer 28 and the at least one cushion layer 20 may extend over at least a portion of the width W and length L of the system 10, and define a portion of the thickness T of the system 10, as shown in FIGS. 1, 2, 8B and 9B. The outer cover layer 28 and the at least one cushion layer 20 are flexible and/or deformable such that they provide cushioning to a user who rests on the top surface 14 (directly or indirectly) of the system 10.

[0072] The at least one cushion layer 20 may comprise at least one foam layer arranged in the width W, length L and thickness T directions. In some embodiments, the at least one cushion layer 20 comprises a single layer. In some other embodiments, the at least one cushion layer 20 comprises a plurality of layers. The at least one cushion layer 20 may include at least one polyurethane layer, such as a viscoelastic foam layer. In some embodiments the at least one cushion layer 20 may comprise a non-polyurethane or viscoelastic foam layer, such as a latex foam layer.

[0073] As shown in FIGS. 1, 2, 8B and 9B, the outer cover layer 28 may extend over the at least one cushion layer 20 along the width W and length L directions, and over/along the lateral and longitudinal sides of the at least one cushion layer 20 along the thickness T direction. The outer cover layer 28 may thereby include, form or define the lateral border portions 22, the longitudinal border portions 23, a top side portion 26 that defines the top side 14 of the system 10, and a bottom side portion 27 that substantially opposes the top side portion 26 and defines the bottom side 16 of the system 10. [0074] In some embodiments, the outer cover layer 28 extends about the at least one cushion layer 20. For example, the outer cover layer 28 may extend fully about the at least one cushion layer 20 such that it fully surrounds, encases or encloses the at least one cushion layer 20. In some other embodiment, the outer cover layer 28 may extend partially about the at least one cushion layer 20 such that it partially surrounds, encases or encloses the at least one cushion layer 20, such as including at least the top side potion 26 along the top side 14 and the lateral border portions 22 and/or the longitudinal border portions 23 (and either not the bottom side portion 27 along the bottom side 16 or partially along the bottom side), for example.

[0075] In some embodiments, the outer cover layer 28 comprises a fabric layer, such as a woven and/or stitched fabric layer. In some embodiments, the outer cover layer 28 comprises a fire resistant layer or sock. The outer cover layer 28 may comprise a minimal amount of stretch such that pressure applied thereto via super-coiled heat-actuating actuators 24 of the system 10, as described further below, only minimally deforms, stretches or deflects the outer cover layer 28 and, thereby, results in compression of the at least one cushion layer 20 in the thickness T direction/dimension.

[0076] As shown in FIGS. 3-9B, the SCHA actuators 24 extending along at least one of the lateral border portions 22 and the longitudinal border portions 23 of the at least one outer cover 28 layer in the thickness direction T. As also shown in FIGS. 3-9B, the SCHA actuators 24 comprise a twisted and coiled elongate member 18 (e.g., a fiber or yam) and a resistive heating element 19 configured to selectively heat the elongate member 18. The elongate member 18 comprises anisotropic thermal expansion such that it includes a length-direction thermal expansion coefficient that is greater than its cross-sectional thermal expansion coefficient. Further, the elongate member 18 is configured such that it at least partially reversibly untwists as the temperature thereof increases.

[0077] The SCHA actuators 24 are thereby configured to selectively and reversibly vary their lengths in the thickness direction, to variably lengthen and shorten the lateral border portions 22 and/or the longitudinal border portions 23 along the thickness direction T, and thereby variably compress the at least one cushion layer 20 in the thickness T direction, to vary the stiffness of the at least one cushion layer 20, as shown in FIGS. 6A-6C, and FIGS. 8 A and 9 A compared to FIGS. 8B and 9B.

[0078] The resistive heating element 19 may be any member or device configured to increase in temperature, such as when a voltage is applied there-across. For example, the resistive heating element 19 may comprise a material that increases in temperature when a voltage is applied thereacross. The resistive heating element 19 may be configured to heat the elongate member 18 via a process of Joule heating. In some embodiments, the resistive heating element 19 comprises a resistive metal material.

[0079] As shown in FIGS. 5, 6A-6C, 8A and 9A, the resistive heating element 19 may be wrapped around the cross-section of the elongate member 18. However, in some other embodiments, as shown in FIG. 6A-6C, the resistive heating element 19 may be wrapped around the coils of the elongate member 18. In some embodiments, the resistive heating element 19 extends adjacent to elongate member 18. In some embodiments, the resistive heating element 19 comprises a coating on the elongate member 18. In some embodiments, the resistive heating element 19 comprises a portion of the elongate member 18, such as an integrated resistive material (e.g., metal material). [0080] In some embodiments, the elongate members 18 of the SCHA actuators 24 (e.g., the twisting and coiling thereof) are configured such that they shorten in length when heated. In some other embodiments, the elongate members 18 of the SCHA actuators 24 (e.g., the twisting and coiling thereof) are configured such that they increase in length when heated.

[0081] The variance of the length of the members 18 via variance in temperature may be due to the internal alignment of the constituents forming the members 18. For example, the elongate members 18 of the SCHA actuators 24 may comprise at least one precursor fiber that has substantial internal alignment of its composition/constituent elements along the length direction. In some embodiments, the twisted nature of the elongate members 18 arranges the constituent elements thereof into helices.

[0082] In some embodiments, the elongate members 18 are pre-stretched to substantially align macromolecules thereof along the length of the members 18. In some embodiments, the constituent elements of the elongate members 18 comprise polymer chains. In some embodiments, the constituent elements of the elongate members 18 comprise nanotubes or nanotube bundles (e.g., carob nanotubes).

[0083] In some embodiments, the elongate members 18 comprise filaments, as shown in FIGS. 3-9A. In some embodiments, the elongate members 18 comprise yarns. In some embodiments, the elongate members 18 comprise polymer yam or filaments, such as nylon yarn or filaments. In some embodiments, the elongate members 18 comprise polymer nanofiber yarns.

[0084] In some embodiments, the elongate members 18 comprise carbon yams with bundles of nanotubes oriented along the length of the members 18. In some embodiments, the elongate members 18 comprise wax-filled yarns made from niobium nanowires and/or graphene-oxide fibers. In some embodiments, the elongate members 18 comprise electrospun fibers of piezoelectric poly(vinylidene fluoride trifluoroethylene) (PVDF-TrFE).

[0085] In some embodiments, the SCHA actuators 24 provide specific work during contraction thereof of at least 2 kJ/kg. In some embodiments, the elongate members 18 of the SCHA actuators 24 are configured to reversibly decrease in length by at least 4% decrease when heated to 110 °C. In some embodiments, the elongate members 18 of the SCHA actuators 24 are configured such that the super-coiled heat-actuating actuators reversibly vary in length along the thickness direction by at least 30% decrease when the temperature thereof is varied by at 30 degrees F.

[0086] In some embodiments, the system 10 may be configured such that the super-coiled heatactuating actuators 24 are controllable such that the stiffness of at least a portion of the at least one cushion layer 20 can be selectively varied between about 5 lbs at 25% IFD to about 120 lbs at 25% IFD. In some embodiments, the system 10 may be configured such that the super-coiled heat-actuating actuators 24 are controllable such that the stiffness of at least a portion of the at least one cushion layer 20 can be selectively varied between about 10 lbs at 25% IFD to about 100 lbs at 25% IFD. In some embodiments, the system 10 may be configured such that the super-coiled heat-actuating actuators 24 are controllable such that the stiffness of at least a portion of the at least one cushion layer 20 can be selectively varied between about 10 lbs at 25% IFD to about 75 lbs at 25% IFD. In some embodiments, the system 10 may be configured such that the super-coiled heat-actuating actuators 24 are controllable such that the stiffness of the at least a portion of the at least one cushion layer 20 can be selectively varied between about 10 lbs at 25% IFD to about 50 lbs at 25% IFD. [0087] In some embodiments, the system 10 may be configured such that the super-coiled heatactuating actuators 24 are controllable such that the stiffness of at least a portion of the at least one cushion layer 20 can be selectively varied between a stiffness range that provides for about/i inch to about 3 inches of deflection of the portion of the at least one cushion layer 20 when a user is supported thereby. In some embodiments, the system 10 may be configured such that the super-coiled heat-actuating actuators 24 are controllable such that the stiffness of at least a portion of the at least one cushion layer 20 can be selectively varied between a stiffness range that provides for about i inch to about 3 inches of deflection of the at least one cushion layer 20 when a user is supported thereby.

[0088] As shown in FIGS. 1 and 2, the system 10 may include/comprise a control unit 50 that is configured to selectively control actuation of the super-coiled heat-actuating actuators 24 and, thereby, selectively variably compress the at least one portion of the at least one cushion layer 20 (specially, the at least one foam layer of the at least one cushion layer 20) between the top portion 26 of the outer cover layer 28 and the bottom portion 27 of the outer cover layer 28 or a support frame/member in the thickness T direction to vary the stiffnesses thereof. The control unit 50 is preferably configured to be manually operable by a user. The control unit 50 may allow for individual selective adjustment (and/or group adjustment) of the super-coiled heatactuating actuators 24, or selective adjustment of groups of the -coiled heat-actuating actuators 24, and thereby selective adjustment or variance of the stiffness/firmness of the at least one cushion layer 20. In this way, a user can vary the stiffness of the at least one cushion layer 20 into any pattern or profile, and in any available/achievable stiffness, as they require or desire. For example, the user can vary the stiffness of the at least one cushion layer 20 over time (e.g., for differing individuals and/or to accommodate changes in stiffness preferences or desires over time).

[0089] As also shown in FIGS. 1 and 2, in some embodiments, the control unit 50 may comprise a remote control device 52 that is configured to be manually operable by a user and control the control unit 50. In some embodiments, as shown in FIG. 1, the remote control device 52 and the control unit 50 are coupled such that the remote control device 52 communicates wirelessly with the control unit 50 (e.g., via infrared, Bluetooth, WIFI, etc.). In one such embodiment, the remote control device 52 may comprise a user’s smartphone, tablet and/or computer. In some embodiments, as shown in FIG. 2, the remote control device 52 and the control unit 50 are coupled via at least one electrical communication wire, and the remote control device 52 communicates with the control unit 50 via the at least one electrical communication wire.

[0090] In some embodiments, the control unit 50 (such as the remote deice 52 thereof, for example) may include one or more visual and/or indicator that indicates the relative stiffness of one or more portions of the system 10 (i.e., the at least one cushion layer 20) that are associated with the super-coiled heat-actuating actuators 24.

[0091] In some embodiments, the control unit 50 comprises memory that includes a plurality of predetermined selectable stiffness profiles that comprise differing stiffnesses and/or differing stiffness distributions of the at least one cushion layer 20 via the super-coiled heat-actuating actuators 24. A user may thereby select one of the profiles to automatically adjust all the supercoiled heat-actuating actuators 24 of system 10, or some or groups of the super-coiled heatactuating actuators 24, according to the selected profile. In one such embodiment, the predetermined selectable stiffness profiles comprise differing stiffness distributions provided by the super-coiled heat-actuating actuators 24, and the predetermined selectable stiffness profiles correspond to identified lying positions of a user. For example, the identified lying positions may comprise at least three lying positions corresponding to the positions of the user lying on their back, on their stomach and on their side.

[0092] As one of ordinary skill in the art would recognize, the systems 10 disclosed herein allow for a user to adjust the stiffnesses of the at least one cushion layer 20 via the super-coiled heatactuating actuators 24 to create any stiffness profile or configuration thereof (via adjustable compression of the at least one cushion layer 20) as desired.

[0093] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. As used herein, the singular forms “a”, “an” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms “comprise” (and any form of comprise, such as “comprises” and “comprising”), “have” (and any form of have, such as “has” and “having”), “include” (and any form of include, such as “includes” and “including”), “contain” (and any form contain, such as “contains” and “containing”), and any other grammatical variant thereof, are open-ended linking verbs. As a result, a method or article that “comprises”, “has”, “includes” or “contains” one or more steps or elements possesses those one or more steps or elements, but is not limited to possessing only those one or more steps or elements. Likewise, a step of a method or an element of an article that “comprises”, “has”, “includes” or “contains” one or more features possesses those one or more features, but is not limited to possessing only those one or more features.

[0094] As used herein, the terms “comprising,” “has,” “including,” “containing,” and other grammatical variants thereof encompass the terms “consisting of’ and “consisting essentially of. [0095] The phrase “consisting essentially of’ or grammatical variants thereof when used herein are to be taken as specifying the stated features, integers, steps or components but do not preclude the addition of one or more additional features, integers, steps, components or groups thereof but only if the additional features, integers, steps, components or groups thereof do not materially alter the basic and novel characteristics of the claimed compositions or methods.

[0096] All publications cited in this specification are herein incorporated by reference as if each individual publication were specifically and individually indicated to be incorporated by reference herein as though fully set forth.

[0097] Subject matter incorporated by reference is not considered to be an alternative to any claim limitations, unless otherwise explicitly indicated.

[0098] Where one or more ranges are referred to throughout this specification, each range is intended to be a shorthand format for presenting information, where the range is understood to encompass each discrete point within the range as if the same were fully set forth.

[0099] While several aspects and embodiments of the present invention have been described and depicted herein, alternative aspects and embodiments may be affected by those skilled in the art to accomplish the same objectives. Accordingly, this disclosure and the appended claims are intended to cover all such further and alternative aspects and embodiments as fall within the true spirit and scope of the invention.

Claims

CLAIMS What is claimed is:

1. An adjustable stiffness body support system, comprising: at least one cushion layer comprising at least one foam layer and defining a length, a width, a thickness, a top side, a bottom side, lateral sides that extend between the top and bottom sides, and longitudinal sides that extend between the top and bottom sides and are positioned between the lateral sides; at least one outer cover layer overlying the at least one cushion layer, comprising a top portion that extends over the top side of the at least one cushion layer, lateral border portions that extend over the lateral sides of the at least one cushion layer, and longitudinal border portions that extend over the longitudinal sides of the at least one cushion layer; and a plurality of super-coiled heat-actuating actuators extending along at least one of the lateral border portions or the longitudinal border portions of the at least one outer cover layer in the thickness direction, each of the super-coiled heat-actuating actuators comprising a twisted and coiled elongate member and a resistive heating element configured to selectively heat the elongate member, wherein the elongate member comprises an anisotropic thermal expansion such that the elongate member includes a length-direction thermal expansion coefficient that is greater than a cross-sectional thermal expansion coefficient of the elongate member, and wherein the super-coiled heat-actuating actuators are configured to selectively and reversibly vary their lengths to variably lengthen or shorten the lateral border portions and/or the longitudinal border portions along the thickness direction, and thereby variably compress the at least one cushion layer in the thickness direction, to vary a stiffness of the at least one cushion layer.

2. The body support system according to claim 1, wherein the elongate member comprises a substantially circular cross-section, and wherein the cross-sectional thermal expansion coefficient of the elongate member comprises a radial thermal expansion coefficient.

3. The body support system according to any of the preceding claims, wherein the plurality super-coiled heat-actuating actuators are arranged along the lateral border portions and the longitudinal border portions.

4. The body support system according to any of the preceding claims, wherein at least three super-coiled heat-actuating actuators are associated with the lateral border portions.

5. The body support system according to any of the preceding claims, wherein at least three super-coiled heat-actuating actuators are associated with the longitudinal border portions.

6. The body support system according to any of the preceding claims, wherein portions of the super-coiled heat-actuating actuators are coupled to the lateral border portions.

7. The body support system according to any of the preceding claims, wherein portions of the super-coiled heat-actuating actuators are coupled to the longitudinal border portions.

8. The body support system according to any of the preceding claims, wherein first end portions of the super-coiled heat-actuating actuators are coupled to the top portion of the at least one cover layer.

9. The body support system according to any of the preceding claims, wherein second end portions of the super-coiled heat-actuating actuators are coupled to the bottom portion of the at least one cover layer.

10. The body support system according to any of the preceding claims, wherein the at least one foam layer comprises at least one polyurethane foam.

11. The body support system according to any of the preceding claims, wherein the at least one foam layer comprises viscoelastic foam.

12. The body support system according to any of the preceding claims, further comprising a frame structure positioned below the at least one cushion layer, the frame structure physically supporting the at least one cushion layer.

13. The body support system according to claim 12, wherein end portions of the plurality of super-coiled heat-actuating actuators are coupled to the frame structure.

14. The body support system according to claims 12 or 13, wherein the at least one outer cover layer extends about the frame structure.

15. The body support system according to any of the preceding claims, wherein the at least one outer cover layer extends about the at least one cushion layer and the plurality of supercoiled heat-actuating actuators.

16. The body support system according to any of the preceding claims, wherein the at least one outer cover layer comprises a fabric layer.

17. The body support system according to any of the preceding claims, wherein the at least one outer cover layer comprises a fire sock.

18. The body support system according to any of the preceding claims, wherein the resistive heating element comprises a material that increases in temperature when a voltage is applied thereacross.

19. The body support system according to any of the preceding claims, wherein the resistive heating element is configured to heat the elongate member via a process of Joule heating.

20. The body support system according to any of the preceding claims, wherein the resistive heating element comprises a resistive metal material.

21. The body support system according to any of the preceding claims, wherein the resistive heating element is wrapped around the cross-section of the elongate member.

22. The body support system according to any of the preceding claims, wherein the resistive heating element is wrapped around the coils of the elongate member.

23. The body support system according to any of the preceding claims, wherein the resistive heating element extends adjacent to the elongate member.

24. The body support system according to any of the preceding claims, wherein the resistive heating element comprises a coating on the elongate member.

25. The body support system according to any of the preceding claims, wherein the resistive heating element comprises a portion of the elongate member.

26. The body support system according to any of the preceding claims, wherein the elongate members of the plurality of super-coiled heat-actuating actuators are configured such that the elongate members shorten in length when heated.

27. The body support system according to any of the preceding claims, wherein the elongate members of the plurality of super-coiled heat-actuating actuators are configured such that the elongate members increase in length when heated.

28. The body support system according to any of the preceding claims, wherein the elongate members of the plurality of super-coiled heat-actuating actuators are configured such that the elongate members at least partially reversibly untwist as the temperature thereof increases.

29. The body support system according to any of the preceding claims, wherein the elongate members of the plurality of super-coiled heat-actuating actuators comprise at least one precursor fiber that has components substantial internal alignment of its composition along the length direction.

30. The body support system according to any of the preceding claims, wherein the elongate members of the plurality of super-coiled heat-actuating actuators comprise yam.

31. The body support system according to any of the preceding claims, wherein the elongate members of the plurality of super-coiled heat-actuating actuators comprise filaments.

32. The body support system according to any of the preceding claims, wherein the elongate members of the plurality of super-coiled heat-actuating actuators comprise polymer yarn or filaments.

33. The body support system according to any of the preceding claims, wherein the elongate members of the plurality of super-coiled heat-actuating actuators comprise nylon yarn or filaments.

34. The body support system according to any of the preceding claims, wherein the elongate members of the plurality of super-coiled heat-actuating actuators comprise yarn or filaments.

35. The body support system according to any of the preceding claims, wherein the elongate members are pre-stretched to substantially align macromolecules thereof along the length of the elongate members.

36. The body support system according to any of the preceding claims, wherein the elongate members are configured to reversibly decrease in length by at least 4% decrease when heated to 110 °C.

37. The body support system according to any of the preceding claims, wherein the elongate members are configured such that the super-coiled heat-actuating actuators reversibly vary in length along the thickness direction by at least 30% decrease when the temperature thereof is varied by at 30 degrees F.

38. The body support system according to any of the preceding claims, wherein the twisted nature of the elongate members arranges the constituent elements of the elongate members in helices.

39. The body support system according to claim 38, wherein the constituent elements comprise polymer chains.

40. The body support system according to any of the preceding claims, wherein the elongate members of the plurality of super-coiled heat-actuating actuators comprise carbon yarns with bundles of nanotubes oriented along the length of the elongate members.

41. The body support system according to any of the preceding claims, wherein the elongate members of the plurality of super-coiled heat-actuating actuators comprise wax-filled yarns made from niobium nanowires and/or graphene-oxide fibers.

42. The body support system according to any of the preceding claims, wherein the elongate members of the plurality of super-coiled heat-actuating actuators comprise polymer nanofiber yarns.

43. The body support system according to any of the preceding claims, wherein the elongate members of the plurality of super-coiled heat-actuating actuators comprise electrospun fibers of piezoelectric. poly(vinylidene fluoride trifluoroethylene) (PVDF-TrFE).

44. The body support system according to any of the preceding claims, wherein the supercoiled heat-actuating actuators are configured to provide specific work during contraction thereof of at least 2 kJ/kg.

45. The body support system according to any of the preceding claims, further comprising a control unit that is configured to selectively control actuation of the super-coiled heat-actuating actuators and, thereby, the thickness of the lateral and/or longitudinal border portions to adjust the compression of the at least one cushion layer, and, thereby, the stiffnesses thereof.

46. The body support system according to claim 45, wherein the control unit is configured to be manually operable by a user.

47. The body support system according to claims 45 or 46, wherein the control unit comprises a remote control device that is configured to be manually operable by a user and control the control unit.

48. The body support system according to claim 47, wherein the remote control device is configured to wirelessly communicate with the control unit.

49. The body support system according to claim 47, wherein the remote control device and the control unit are coupled via at least one electrical communication wire.

50. The body support system according to any of claims 45-49, wherein the control unit comprises a plurality of predetermined selectable stiffness profiles that comprise differing lengths of the super-coiled heat-actuating actuators and, thereby, differing stiffnesses and/or differing stiffness distributions of the at least one cushion layer.

51. The body support system according to claim 50, wherein the predetermined selectable stiffness profiles comprise differing stiffness distributions corresponding to identified lying positions of a user.

52. The body support system according to claim 51, wherein the identified lying positions comprise at least three lying positions corresponding to positions of the user lying on their back, on their stomach and on their side.

53. The body support system according to any of claims 45-52, wherein the control unit comprises one or more visual indicator that indicates the relative stiffness of at least one portion of the at least one cushion layer.

54. The body support system according to any of the preceding claims, wherein the stiffness of at least a portion of the at least one cushion layer can be selectively varied via the super-coiled heat-actuating actuators between about 5 lbs at 25% IFD to about 120 lbs at 25% IFD.

55. The body support system according to any of the preceding claims, wherein the stiffness of at least a portion of the at least one cushion layer can be selectively varied via the super-coiled heat-actuating actuators between about 10 lbs at 25% IFD to about 100 lbs at 25% IFD.

56. The body support system according to any of the preceding claims, wherein the stiffness of at least a portion of the at least one cushion layer can be selectively varied via the super-coiled heat-actuating actuators between about 10 lbs at 25% IFD to about 75 lbs at 25% IFD.

57. The body support system according to any of the preceding claims, wherein the stiffness of at least a portion of the at least one cushion layer can be selectively varied via the super-coiled heat-actuating actuators between about 10 lbs at 25% IFD to about 50 lbs at 25% IFD.

58. The body support system according to any of the preceding claims, wherein the stiffness of at least a portion of the at least one cushion layer can be selectively varied via the super-coiled heat-actuating actuators between a stiffness range that provides for about Yi inch to about 3 inches of deflection of the at least one cushion layer when the user is supported thereby.

59. The body support system according to any of the preceding claims, wherein the system is configured as a mattress system.

60. The body support system according to any of the preceding claims, wherein the system is configured as a cushion system.

61. A method for adjusting a firmness of a body support system, comprising: providing or obtaining the body support system of any of the previous claims; and selectively varying the length of the super-coiled heat-actuating actuators along the thickness direction via utilizing the resistive heating elements to vary the temperature of the actuators to variably compress the at least one cushion layer and adjust the stiffnesses thereof.

40