GB2602094A

GB2602094A - Method of designing a bespoke compression garment incorporating a transition from one material to another

Info

Publication number: GB2602094A
Application number: GB2020040.8A
Authority: GB
Inventors: Harwood Adam; Gunther Clive; Hassan Chaudhury Najmal; Sopper James
Original assignee: Advanced Therapeutic Materials Ltd
Current assignee: Advanced Therapeutic Materials Ltd
Priority date: 2020-12-17
Filing date: 2020-12-17
Publication date: 2022-06-22
Also published as: GB202020040D0; WO2022129920A1

Abstract

Bespoke compression garment 10 with transition point 16 between two fabrics 12, 14 wherein at the transition point 16 there is a first fabric course 15 of the first fabric 12 having first number of needles and loop size for imparting a first pressure on a first position of a body part, and a transition zone 16 between the first course 15 and a second course 17 of the second fabric 14 having second needle number and loop size, the transition zone 16 having transitionary course configured to maintain specified pressure from the first 15 to the second 17 course, wherein the number of needles of the transitionary course 16 is optimised to reduce the jump in number of needles between the first 15 and second 17 courses. Also claimed is a computer-implemented method of designing a bespoke compression garment by obtaining a representation and determining circumferences of a body part, determining respective pressure for each circumference and identifying transition points on the garment, calculating the difference in needle number between first and second fabrics, introducing a transitionary course if the number difference exceeds a threshold number.

Description

METHOD OF DESIGNING A BESPOKE COMPRESSION GARMENT INCORPORATING A TRANSITION FROM ONE MATERIAL TO ANOTHER

Field of the Invention

This invention relates to a computer-implemented method of designing a bespoke compression garment. The invention further relates to a method of manufacturing such a compression garment, to a compression garment manufactured by such a method, and to a computer program for carrying out the design method.

Background to the Invention

Compression garments are worn on a person's or patient's body part and apply pressure to the body part, typically to improve blood circulation (in particular venous return) therein. This can help to improve or cure a number of different health conditions or may address other medical needs.

Compression garments are commonly worn on limbs, for example on the leg and/or foot. For example, when designed to envelop at least part of a foot and/or leg of the wearer, such compression garments may be termed compression stockings or compression socks. It should be noted, though, that although the exemplary compression garments in the present disclosure are generally illustrated and described as covering the wearer's foot, this need not necessarily be the case. For instance, when worn in use, the compression garment need not necessarily extend to cover the wearer's toes, and instead may take the form of a sleeve that is open at both ends. Alternatively, the compression garment may take the form of a sleeve that is worn on the wearer's arm.

Compression garments are conventionally knitted. Knitting, rather than weaving, may be used for compression garments since knitting is suited to cylindrical garments and compression garments are typically cylindrical. As such, knitted compression garments are quicker and more cost effective to manufacture than woven garments and may provide greater comfort than woven garments.

A knitted compression garment may typically comprise a plurality of courses or bands of fabric (which may also be referred to herein as "fabric courses" or "material courses"; the terms "fabric" and "material" are used interchangeably herein). These fabric courses have a circumference which, when at rest (i.e. unstretched), is smaller than a circumference of the associated body part. As such, the courses are required to be strained to be worn over the body part, which causes a pressure to be applied on the body part.

Since people's limbs vary in shape and size from person to person, it is desirable for a compression garment to be customised for a specific wearer, to provide the wearer with a specified pressure configuration along the length of the garment in use, e.g. along at least part of the wearer's foot and/or leg. Such a compression garment may be referred to as a bespoke compression garment. In such a case, the pressure configuration may for example be prescribed by a clinician or healthcare professional, to suit the wearer's particular health condition or other medical needs.

To provide a required pressure configuration (e.g. a pressure gradient) along the length of the compression garment, the garment may have a graduated structure, whereby the fabric courses have different properties at different places along the garment. The therapeutic benefits of well-fitting, graduated compression garments are well known, and may be used to provide effective long-term management of chronic medical conditions, improved rates of recovery for many venous conditions, or prophylactic effects to reduce the likelihood of onset or recurrence of venous diseases, as well as improved rates of muscle recovery after physical exertion.

One of the properties of the materials used in compression garments is stiffness -a material's resistance to stretching. The stiffer the material, the more resistant it is to increased stretch. It is this resistance and indeed the material's inherent propensity to return to its original size once stretched that induces tension in the material and thus interface pressure when applied to a curved surface.

Traditional tubular manufacture (socks, arm sleeves etc.) utilise circular knitting technology; a fixed array of machine knitting needles arranged in a circle. During the knitting process needles cannot be added or removed, so in order to shape a garment the tension and loop size of the yarn is either increased or decreased between the array of needles; a larger loop size leads to an increase in the diameter of the garment whereas a small loop size will decrease the diameter. The resultant impact of increasing the loop size is to decrease the stiffness of the material, while decreasing the loop size increases the stiffness, and as a result the parts of the garment covering wider anatomical sections typically have a lesser stiffness than those covering narrower sections.

It may be desirable to produce a garment that does not follow this pattern, having a greater stiffness on a wider body part (the calf of the leg, for example) in comparison to a narrower body part (the ankle, for example). Indeed, it has been shown in clinical study that high calf stiffness is desirable and increases venous return during motion, while at the same time it is desirable to maintain a comfortable ankle pressure and a low ankle stiffness to allow the garment to be donned (and doffed) easily (typically the relatively small ankle part must be stretched over the relatively large heel part during donning and doffing -a process made much easier with a less stiff fabric). This is just one example of where a controlled change in stiffness (increase or decrease) may be desirable; other examples will be apparent to those skilled in the art.

Whilst it is not a new concept that a garment (in a general sense) may have different sections having different properties, it is not typically possible to do this within the structure of a compression garment. To achieve desired performance (stiffness increasing up the leg, for example) without compromising the controlled, graduated nature of the compression, accurate control of the garment structure is required, along with accurate and predictable control of the fabric properties during garment construction.

However, accurate control of interface pressure provided by a compression garment is notoriously difficult, with complexity introduced at the measurement stage (accurate measurement of a limb is not easy), the design stage (each stitch in the garment must be designed and controlled for, to prevent inconsistency), and the manufacturing stage (variations introduced by the knitting machines used must be controlled for, or eliminated).

Each region of material within a compression garment comprising a different property (in this example, stiffness) can be considered to be a different material (or different fabric) in its own right. However, a particular problem in the design of a compression garment is controlling the transition from one material (or fabric) to another, without sacrificing the desired stiffness or interface pressure at that location on the garment. Expressed another way, it can be difficult to control the transition from a first fabric having a first level of stiffness to a second fabric having a second level of stiffness whilst providing a desired pressure gradient across the two fabrics. In this regard, some pre-existing compression garments represent an unsatisfactory trade-off, whereby the garments are easy to put on but have a low stiffness, or have a high stiffness but are difficult to put on; in both cases such garments do not enable a desired pressure gradient to be properly provided without sacrificing stiffness and/or ease of application.

There is therefore a desire to address the above problems, to produce a method of designing a bespoke compression garment in which the transition between different fabrics is controlled in such a manner as to maintain the desired stiffness and interface pressure at that location on the garment, across the transition region.

Summary of the Invention

According to a first aspect of the present invention there is provided a computer-implemented method as defined in Claim 1 of the appended claims. Thus there is provided a computer-implemented method of designing a bespoke compression garment, the method comprising: (a) obtaining a representation of a body part on which the compression garment is to be worn; (b) determining, from the representation, a respective series of circumferences along the body part; (c) obtaining a specified pressure configuration to be applied by the compression garment on the body part; (d) determining a respective pressure for each of the series of circumferences, based on the specified pressure configuration, (e) identifying a transition point on the compression garment, at which transition point a first fabric is to begin a transition to a second fabric, the transition point corresponding to a first position along the body part having a respective first circumference, at which a respective first pressure is to be applied by the compression garment, wherein, at the transition point, a first fabric course of the first fabric is to be used, the first fabric course having a first loop size, for imparting the first pressure on the first position of the body part; (f) calculating a first number of needles required in respect of the first fabric course in order to impart the first pressure on the first position of the body part, based on the first circumference; (g) identifying an initial position of a second fabric course of the second fabric, corresponding to an initial second position along the body part having a respective second circumference at which a respective second pressure is to be applied by the compression garment, wherein, at the initial position, the second fabric course has a second loop size, for imparting the second pressure on the initial second position of the body part; (h) calculating a second number of needles required in respect of the second fabric course in order to impart the respective second pressure on the initial second position of the body part, based on the second circumference; (i) calculating the difference between the first number of needles and the second number of needles; if the difference between the first number of needles and the second number of needles is less than or equal to a threshold number, (j) generating a set of knitting instructions for producing the compression garment, including the first fabric course having the first number of needles and the second fabric course in its initial position having the second number of needles; if the difference between the first number of needles and the second number of needles is greater than the threshold number, (k) introducing, after the first fabric course, a transition zone comprising at least a first transitionary course of the first or second fabric, with the initial position of the second fabric course being shifted to after the transition zone; (I) identifying the respective circumference of the body part and the respective pressure for the introduced transitionary course; (m) calculating, for the introduced transitionary course, an optimal number of needles required to impart the respective pressure on the respective circumference of the body part, whilst avoiding a jump of more than the threshold number of needles between the preceding fabric course and the introduced transitionary course, wherein the number of needles of the introduced transitionary course is optimised to reduce the jump in number of needles between the introduced transitionary course and the second fabric course in its shifted position, by varying the loop size and/or knit style of the introduced transitionary course; (n) calculating the difference between the number of needles of the introduced transitionary course and a calculated number of needles of the second fabric course in its shifted position; if the difference between the number of needles of the introduced transitionary course and the number of needles of the second fabric course in its shifted position is less than or equal to the threshold number, (o) generating a set of knitting instructions for producing the compression garment, including the first fabric course having the first number of needles, the transition zone in which the number of needles changes from the first number of needles to the second number of needles, and the second fabric course in its shifted position having the second number of needles; if the difference between the number of needles of the introduced transitionary course and the number of needles of the second fabric course in its shifted position is greater than the threshold number, (p) introducing a further transitionary course in the transition zone, shifting the position of the second fabric course further, and repeating from step (I) above.

One advantage of the present invention is the ability to use multiple fabrics within the compression region of the garment without detriment to the applied pressure gradient. Indeed, we have found that a single fabric cannot provide all the functionality required of the garment, in terms of maintaining stiffness and interface pressure along the compression region, whilst also not being unduly difficult to put on or take off.

Accordingly, by virtue of the present invention, a more satisfactory transition between different fabrics can be achieved, enabling the desired stiffness and interface pressure to be maintained across the transition between the different fabrics. As a result, by enabling multiple fabrics to be used in this manner, this allows for better customisation of the stiffness profile and pressure profile of the garment, leading to a better preforming garment.

In certain embodiments the transition zone comprises: a first transitionary course of the first fabric, at the start of the transition zone, adjacent to the first fabric course; and a second transitionary course of the second fabric, at the end of the transition zone, adjacent to the second fabric course in its shifted position; and the method further comprises: antagonistically adjusting the loop size of the first transitionary course and the loop size of the second transitionary course, starting from the first loop size and the second loop size respectively.

By way of example, in presently-preferred embodiments the abovementioned threshold number of needles is two (although other numbers are also possible, such as three or four).

In certain embodiments the representation of the body part comprises scan data (for example 3D scan data) of the body part.

According to a second aspect of the invention there is provided a method according to the first aspect of the invention; and manufacturing the compression garment by knitting the fabrics in accordance with the generated set of knitting instructions.

According to a third aspect of the invention there is provided a compression garment made by the method according to the second aspect of the invention. The garment as produced by the method is different to garments not formed by the method. Preferably the garment is flat knit.

According to a fourth aspect of the invention there is provided a computer program comprising instructions which, when the program is executed by a computer processor, cause the computer processor to carry out the method according to the first or second aspect of the invention.

According to a fifth aspect of the invention there is provided a bespoke compression garment comprising: a transition point at which a first fabric begins a transition to a second fabric, wherein, at the transition point, a first fabric course of the first fabric is provided, the first fabric course having a first number of needles and a first loop size, for imparting a first pressure on a first position of the body part; and a transition zone after the first fabric course, and before a second fabric course of the second fabric, the second fabric course having a second number of needles and a second loop size, for imparting a second pressure on a second position of the body part; wherein the transition zone comprises one or more transitionary courses of the first or second fabric, the or each transitionary course being configured to maintain a specified pressure configuration from the first fabric course to the second fabric course; and wherein the number of needles of the or each transitionary course is optimised to reduce the jump in number of needles between the first fabric course, the or each transitionary course, and the second fabric course, by varying the loop size and/or knit style of the or each transitionary course.

Brief Description of the Drawings

Embodiments of the invention will now be described, by way of example only, and with reference to the drawings in which: Figure 1 illustrates an example of a bespoke compression garment comprising first and second fabrics; Figure 2 illustrates typical characteristic data in respect of three candidate materials from which a fabric of a bespoke compression garment may be made, showing the relationship between exerted pressure and strain; Figure 3 is a procedural flow diagram of a method (algorithm) of designing a bespoke compression garment as in Figure 1, whereby a transition zone (comprising one or more transitionary courses) may be introduced in order to control the transition from the first fabric to the second fabric whilst maintaining desired properties across the region of the transition; Figure 4 illustrates a bespoke compression garment for which a transition zone is not required to be introduced between the first and second fabrics; Figure 5 illustrates the design of a bespoke compression garment (a) before having a transition zone inserted, and (b) after having a transition zone (in this case comprising one transitionary course) inserted between the first and second fabrics; Figure 6 illustrates a bespoke compression garment having a transition zone (in this case comprising two transitionary courses) inserted between the first and second fabrics; Figure 7 illustrates a process of antagonistically adjusting two transitionary courses within the transition zone, (a) before adjustment, and (b) after adjustment; and Figure 8 illustrates an example of a set of knitting instructions (i.e. a knitting file) for a bespoke compression garment, as produced by the design method.

In the figures, like elements are indicated by like reference numerals throughout.

Detailed Description of Preferred Embodiments

The present embodiments represent the best ways known to the Applicant of putting the invention into practice. However, they are not the only ways in which this can be achieved.

In a general sense, the present invention provides, amongst other things, a software method (algorithm) for evaluating and designing a controlled transition in a compression garment between two fabrics with different properties while maintaining the key requirements of the compression garment -i.e. the applied pressure and the pressure gradient across the transition.

To achieve this, as discussed below, an accurate limb measurement methodology should be followed, a controlled process to design the garment should be adhered to, and the manufacturing process should also be tightly controlled.

Overview of a compression garment Figure 1 illustrates an example of a bespoke knitted compression garment 10 as may be designed and manufactured using embodiments of the present invention. In the illustrated example the compression garment 10 is in the form of a compression stocking. The knitted compression garment is tubular or substantially tubular in form, and comprises a plurality of fabric courses. For flat knitted garments in weft knitting, each fabric course may be considered to be a band, ring or circle of yarn. Adjacent courses or bands of yarn have interconnected or interknitted loops or bights. Preferably, the fabric courses are flat knitted.

The compression garment 10 comprises a first fabric 12 and a second fabric 14. A transition point TP (as discussed in greater detail below) is identified between the first fabric 12 and the second fabric 14. The compression garment 10 is designed to impart a specified pressure configuration or pressure gradient P, e.g. as prescribed by a healthcare professional, on the wearer's limb (in this example, their foot and leg).

Relationship between pressure and strain for elastic fabrics To introduce a concept that will be referred to later, Figure 2 illustrates typical characteristic data in respect of three candidate elastic fabric materials (A, B and C) from which the fabric of a compression garment may be made, showing the relationship between exerted pressure (in mmHg) and strain, for a given radius of curvature of the compression garment.

Typical compression garments are constructed from both a body yarn (for the purpose of delivering stiffness) and an inlay yarn (for the purpose of delivering pressure). While this is not limited, we have found that using a typical inlay yarn as the body yarn produces suitable stress/strain gradients in the resulting garment.

Conventionally, manufacturers have not used inlay yarns as body yarns as they are unable to produce consistent results due to their typical elasticities. However, we have found that, by using a suitable tension control device (e.g. as described in WO 01/77427 Al and WO 2005/014903 A2), we are able to use inlay yarns as a body yarn and knit with consistent results When designing a compression garment, it is preferable to have a database of suitable fabrics to deliver different amounts of pressure for a given radius of curvature. For instance, for a given radius of curvature, one fabric may deliver 30mm Hg of pressure at 50% strain, while another may deliver 10m mHg of pressure at the same 50% strain.

Method of designing a bespoke compression garment incorporating a transition from a first fabric to a second fabric An embodiment of the present invention will now be described, primarily with reference to Figure 3, and also with reference to Figures 1 and 4 to 6. This provides a computer-implemented method (algorithm) of designing a bespoke compression garment 10 having a first fabric 12 and a second fabric 14, as illustrated in overview in Figure 1.

More particularly, Figure 3 is a detailed procedural flow diagram 20 that illustrates the present design method. The steps of the method may in practice be implemented by a suitably-programmed microprocessor (e.g. forming part of a computer or part of a processing system). A program which, when executed by the microprocessor or computer, causes the microprocessor, computer or system to carry out the method, is also provided by the present disclosure.

In overview, the method comprises the following steps: (a) Obtaining a representation of a body part on which the compression garment 10 is to be worn (box 21 of Figure 3).

(b) Determining, from the representation, a respective series of circumferences along the body part (box 22).

(c) Obtaining a specified pressure configuration P to be applied by the compression garment 10 on the body part (box 23).

(d) Determining a respective pressure for each of the series of circumferences, based on the specified pressure configuration P (box 24).

(e) Identifying a transition point TP on the compression garment 10, at which transition point the first fabric 12 is to begin a transition to the second fabric 14, the transition point TP corresponding to a first position along the body part having a respective first circumference, at which a respective first pressure is to be applied by the compression garment 10 (box 25), wherein, at the transition point TP, a first fabric course 15 (see Figures 4-6) of the first fabric 12 is to be used, the first fabric course 15 having a first loop size, for imparting the first pressure on the first position of the body part.

(f) Calculating a first number of needles required in respect of the first fabric course 15 in order to impart the first pressure on the first position of the body part, based on the first circumference (box 26).

(g) Identifying an initial position of a second fabric course 17 of the second fabric 14, corresponding to an initial second position along the body part having a respective second circumference at which a respective second pressure is to be imparted by the compression garment 10 (box 27), wherein, at the initial position, the second fabric course 17 has a second loop size, for imparting the second pressure on the initial second position of the body part.

(h) Calculating a second number of needles required in respect of the second fabric course 17 in order to impart the respective second pressure on the initial second position of the body part, based on the second circumference.

(i) Calculating the difference between the first number of needles and the second number of needles (box 29).

If the difference (box 30) between the first number of needles and the second number of needles is less than or equal to a threshold number, the method then 10 comprises: (j) Generating a set of knitting instructions for producing the compression garment 10, including the first fabric course 15 having the first number of needles and the second fabric course 17 in its initial position having the second number of needles (box 31).

In a presently-preferred embodiment the threshold number is two. However, in alternative embodiments the threshold number may be a higher number, such as three or four, for example.

An example resulting compression garment 10 is shown in Figure 4, in which the first fabric course 15 is immediately adjacent the second fabric course 17. That is to say, as the difference between the first number of needles and the second number of needles is less than or equal to the threshold number, no transition zone is required to be inserted between the first fabric course 15 and the second fabric course 17, and the position of the second fabric course 17 does not need to be adjusted to accommodate any such transition zone. Rather, the first fabric course 15 can immediately transition to the second fabric course 17 with no detrimental effect on the pressure gradient P applied across the two fabrics 12, 14.

On the other hand, and as shown by way of illustration in Figure 5(a), if the difference between the first number of needles and the second number of needles is greater than the threshold number (outcome "No" of box 30), such that an abrupt change would otherwise occur between the first fabric course 15 and the second fabric course 17, the method proceeds, with reference to Figure 5(b), by introducing a transition zone 16 between the first fabric course 15 and the second fabric course 17, with the initial position of the second fabric course 17 being shifted to accommodate the transition zone 16. That is to say, the method further comprises: (k) Introducing, after the first fabric course 15, a transition zone 16 comprising at least a first transitionary course 16a of the first or second fabric, with the initial position of the second fabric course 17 being shifted to after the transition zone 16 (box 32).

(I) Identifying the respective circumference of the body part and the respective pressure for the introduced transitionary course 16a (box 33).

(m) Calculating, for the introduced transitionary course 16a, an optimal number of needles required to impart the respective pressure on the respective circumference of the body part, whilst avoiding a jump of more than the threshold number of needles between the preceding fabric course and the introduced transitionary course 16a (box 34), wherein the number of needles of the introduced transitionary course 16a is optimised to reduce the jump in number of needles between the introduced transitionary course 16a and the second fabric course 17 in its shifted position, by varying the loop size and/or knit style of the introduced transitionary course 16a.

(n) Calculating the difference between the number of needles of the introduced transitionary course 16a and a calculated number of needles of the second fabric course 17 in its shifted position (box 35).

If the difference (box 36) between the number of needles of the introduced 30 transitionary course 16a and the number of needles of the second fabric course 17 in its shifted position is less than or equal to the threshold number (outcome "Yes" from box 36), the method then comprises: (o) Generating a set of knitting instructions for producing the compression garment 10, including the first fabric course 15 having the first number of needles, the transition zone 16 in which the number of needles changes from the first number of needles to the second number of needles, and the second fabric course 17 in its shifted position having the second number of needles. An example resulting compression garment 10 is shown in Figure 5(b), in which the second fabric course 17 is separated from the first fabric course 15 by the transition zone 16 comprising the transitionary course 16a.

On the other hand, and with reference now to Figure 6, if the difference in the number of needles between the introduced transitionary course 16a and the number of needles of the second fabric course 17 in its shifted position is still greater than the threshold number (outcome "No" of box 36), the method further comprises: (p) Introducing a further transitionary course 16b in the transition zone 16, shifting the position of the second fabric course 17 further (box 38), and repeating from step (I) above, where the said "introduced transitionary course" is now 16b.

By means of this iterative process, once sufficient transitionary courses have been provided in the transition zone 16, the outcome of box 36 will eventually become "Yes". That is to say, the difference in the number of needles between the introduced transitionary course (e.g. 16b) and the number of needles of the second fabric course 17 in its shifted position has become less than or equal to the threshold number. This enables the process to proceed to step (o), namely: (o) Generating a set of knitting instructions for producing the compression garment 10, including the first fabric course 15 having the first number of needles, the transition zone 16 in which the number of needles changes from the first number of needles to the second number of needles, and the second fabric course 17 in its shifted position having the second number of needles. To illustrate this, Figure 6 shows an example resulting compression garment 10 in which the second fabric course 17 is separated from the first fabric course 15 by the transition zone 16 which, in this example, comprises two transitionary courses, 16a and 16b.

It should be noted that, in the above method, each transitionary course within the transition zone may comprise a single fabric course, or alternatively, multiple identical fabric courses may be provided in respect of each distinct transitionary course.

Further details of the steps of the above method The steps of the above method will now be explained in greater detail.

Step (a) -obtaining a representation of a body part on which the compression garment is to be worn In step (a) the system obtains a representation (e.g. 3D scan data) of the body part of the intended wearer of the compression garment, onto which body part the compression garment is to be worn.

The obtaining of such scan data may be performed by scanning the body part of the intended wearer. Alternatively, data generated by a previously-carried-out scan (potentially by a different entity, in potentially a different geographical location) may 20 be obtained. From the scan data, a representation of the body part may be obtained.

The scanning may be undertaken by any appropriate scanning means or scanning setup. For example, the scanning may be carried out by a healthcare professional using a camera, such as that on a portable electronic device such as a tablet, to take images or record video of the body part from multiple angles or perspectives.

Scanning software may then transform such images or video into a representation, in other words a model or three-dimensional model, of the body part which comprises a plurality of datapoints or vertices. The representation or model is an electronic or computer implemented representation. The representation comprises the plurality of datapoints.

For convenience, when scanning a leg or foot, the scanning may be done with the patient or user having their legs spaced apart and therefore at an angle to a vertical direction. The representation may be provided by the scanning software with respect to a conventional Cartesian coordinate system. As such, the representation, or a longitudinal extent thereof, which is produced via such scanning may be offset relative to an axis which indicates the vertical direction, typically the z-axis, compared to an in-use arrangement. The rotation of said representation may therefore be necessary and will be better understood hereinbelow.

Whilst a scanning process has been described, it will be appreciated that this may not be necessary to the invention and a representation of the body part may instead be provided from an alternative source.

Moreover, whilst a three-dimensional (3D) scanning process has been described, and is generally preferable, the use of 3D data is not essential to the present invention. For instance, individual body part measurements (e.g. made by the healthcare professional using a measuring device) may be used instead.

The scan or representation may then be provided to a processor or system by the healthcare professional, along with other information such as a desired pressure configuration to be applied by the garment, the colour of the compression garment, 20 and the number of garments.

The representation, having been produced by scanning e.g. a leg and/or foot, may be misoriented and therefore may be a misoriented representation. In other words, the representation is in an orientation or at angle relative to the z-axis of the coordinate system which is not representative of the body part when the patient or user is in a typical standing condition. As such, said misoriented representation should be transformed or rotated to a correctly oriented condition, having an orientation relative to said z-axis which is representative of the body part when the patient or user is in a typical standing condition.

If the body part has areas or portions which are at an angle to each other, the representation should be appropriately, and preferably automatically, analysed to determine the location of these areas. This is for the purpose of modelling the likely geometry and orientation of material courses of the garment, when worn on the body part, as representation courses on the representation. This will be understood with reference to the leg and the foot, where it will be appreciated that an axial direction of the material courses of the foot area of the tubular compression stocking will be parallel or substantially parallel or aligned or substantially aligned with a horizontal axis when worn on the body. Contrastingly, an axial direction of the material courses of the leg area of the tubular compression stocking will be parallel or substantially parallel or aligned or substantially aligned with a vertical axis when worn on the body. Therefore, the foot and leg areas of the body should be identified so that representation courses can be appropriately modelled around the relevant body part area. This may be achieved by determining at least one transition point which characterises a transition between leg and foot.

The orientation and geometry of the representation courses are preferably set to accurately reflect the material courses of the garment. For example, the axial direction of each of the representation courses of the foot portion should be oriented so as to be horizontal or substantially horizontal. Similarly, the axial direction of each of the representation courses of the leg portion is orientated so as to be vertical or substantially vertical.

Those representation courses of the leg and foot which are proximate to the heel may be modelled to be non-planar, for example being curved. Thus, the geometry of the representation courses should reflect this to accurately model the material courses. Thus is since, if the non-planar or curvate character of the courses is not modelled, an accurate value of circumference of the non-planar or curvate course cannot be calculated given that a non-planar course typically has a greater circumference than a planar course.

The method preferably comprises a step of the system dividing the representation into the plurality of representation courses, based on a length of the desired garment and the height or spacing of each course. In other words, bands are defined around the representation, the bands having a given height. For example, the garment or representation may be 300 mm in length, and an average or typical course height may be 0.75 mm, resulting in 400 representation courses defined around the representation. The course height may be selected based on the type of material for the yarn, and/or the desired properties of the garment. Other garment lengths and course heights may be considered.

Non-planar material courses of a garment when worn on a body part are typically more stretched (longitudinally) at the back, and less stretched or looser at the front. As such the system or processor preferably adjusts the curved or non-planar representation courses to have a greater course height at or adjacent to the front and a lesser course height at or adjacent to the rear. As such, the course height of the non-planar representation courses may not be uniform.

In a similar way, material courses having a greater circumference value may have a lower course height due to manufacturing techniques. So different representation courses may have different course heights depending on the circumference.

Although it is preferable that material courses having a greater circumference value may have a lower course height, it will be appreciated that this may not be the case. For example, a uniform course height may be used providing a given number of courses for a given height of garment. The value of the course height may then be refined and adjusted using an algorithm which predicts the variance of course height due to the manufacturing technique.

A set of datapoints for each representation course may be selected by the processor, each set of datapoints being located within the corresponding representation course. In other words, the datapoints which have coordinates within the boundaries defined the representation courses are grouped into sets associated with the relevant representation courses.

Those sets which are associated with representation courses which are planar or substantially planar may be modelled as flat. The difference in height or z-axis position between datapoints of such a set which may arise due to the non-zero value of the course height may be disregarded.

A spline, and in particular a basis spline or B-spline, function of best fit may be calculated by the system based on the datapoints of each planar set. Although a spline is presently preferred, it will be appreciated that other curve fitting or curve approximation techniques or functions may be considered. Since the spline is calculated based on the raw datapoints, rather than based on an approximation of the datapoints or based on boundary curves, contours or surfaces which are in turn based on the datapoints, the spline is more representative of the body part.

Before calculating the spline, the datapoints may be required to be centred around x and y axes. This can be done via calculating the average of the x-axis position value of the datapoints and subtracting it from the x-axis position of each datapoint. The same process is done relative to the y-axis. The datapoints can then be converted to polar coordinates to obtain an angular, or azimuth, value of each datapoint around a centre or origin of the datapoints. The datapoints are then sorted by the angular, or azimuth, value. This is to prevent or limit the datapoints being assigned an incorrect order around the origin when calculating the spline. The B-spline can then be calculated.

For sets of datapoints associated with non-planar courses, at least some of the datapoints may have differences in height or z-axis position which require consideration to provide a spline which is representative of the associated material course. As such, if the non-planar representation is modelled as two planar portions at an angle to each other, one planar portion may be rotated relative to the other planar portion so as to be coplanar. For example, the portion which is at an angle to the x-y plane is rotated so as to be parallel with the x-y plane. This rotation may be done in a similar or identical way as the rotation of the representation relative to the z-axis as previously described.

Having rotated or transformed the datapoint set of the or each non-planar representation course, a B-spline may be calculated as previously described.

Step (b) -determining, from the representation, a respective series of circumferences along the body part It will be appreciated that a compression garment is a series of courses stitched together, each course having a height (or length), such that a collection of the stitched courses has a total height (or length). Each course can then be seen as a point along the body part, with that point having a circumference Circumference can be calculated in a variety of ways.

For example, if the representation of the body part is 3D data, the data points that lie on that point on the body part can be selected. This may be done via the formula: C = (x'2 + y'2)°*5 Where C is the circumference of the spline, x' is a first derivative of x for example the first derivative of x with respect to y, and y' is a first derivative of y for example the first derivative of y with respect to x. It will be appreciated that the x-y plane is transverse across the body part, orthogonal to the longitudinal z-axis.

Alternatively, if the representation of the body part comprises clinician-provided measurements at set heights from the ground, the circumference for each point can be calculated by using a linear or non-linear gradient between each provided circumference to predict the circumference measurement.

Step (c) -obtaining a specified pressure configuration to be applied by the compression garment on the body part In this step, a specified pressure profile or pressure configuration is obtained, that is to be applied by the compression garment on the wearer's body part when worn.

The pressure configuration may be prescribed by a healthcare professional, based on a patient's requirement. The pressure configuration may be a uniform pressure arrangement, such that the garment is intended to provide a uniform pressure across the garment, or a graduated pressure configuration, such that the garment is intended to apply a higher pressure at one portion of the garment and a decreasing pressure away from this portion; or some other different pressure arrangement.

The pressure configuration may be input to the processor or system at the same time as the representation or datapoints are provided to the processor or system. Values of pressure which a garment may apply may be provided in millimetres of mercury (mmHg). Typical clinical values of pressure clinically desirable to apply may be between 10 mmHg and 50 mmHg (1333 Pa and 6666 Pa).

A pressure configuration can be created using a linear pressure gradient between a clinically-required starting pressure at one part of the garment and a clinically-required end pressure at another part of the garment, and the number of courses established in step (b).

Step (d) -determining a respective pressure for each of the series of circumferences, based on the specified pressure configuration Following step (c), in step (d) each of the series of circumferences from step (b) is assigned a respective pressure that is required to be delivered.

Step (e) -identifying a transition point TP at which a first fabric course 15 of the first fabric 12 is to be used, having a first loop size, for imparting a first pressure The transition point TP may be anywhere on the body part, between the first fabric 12 and the second fabric 14.

As used herein, a "fabric" may be considered to be a knitted material consisting of a yarn, a knitting style and a loop size. The combination of these characteristics defines the fabric's stiffness, which in turn defines its pressure delivery characteristics. For example, depending on their pressure delivery characteristics, two different fabrics of the same size may deliver different amounts of pressure.

Step (f) -calculating a first number of needles required in respect of the first fabric course 15 in order to impart the first pressure on the first position of the body part, based on the first circumference As illustrated in Figure 2, for any given fabric the pressure delivery characteristics can be defined using a linear relationship, e.g. on a plot of pressure vs strain as shown, with each fabric having an associated gradient of material coefficient VJmc and a respective y-intercept of material coefficient ymc.

The y-intercept of material coefficient ynt, may be considered an equipment normalisation stress.

The gradient of material coefficient Vm, may be equivalent to, similar to or dependent upon the Young's modulus of the fabric.

Firstly, in this regard, the pressure applied by a course of a given fabric is generally calculated according to the following equation: P -Ymc ± me E where p is the pressure applied by the course, ym, is the y-intercept of material coefficient (from a plot as in Figure 2), Vr",, is the gradient of material coefficient (likewise from a plot as in Figure 2), E is strain of the course, and r is the radius of curvature of the course (equal to the respective circumference divided by 2-rr).

Rearranging the above equation gives the strain E of the course necessary to apply the desired pressure p as Pr Yrnc

E

V inc.

The calculated strain E for the given fabric is then converted into an unstretched garment circumference Co for the course in question using the following equation: CO= C13 P 1 + c where Cgp is the circumference of the body part around which the course is to be applied (i.e. 2-rrr).

The number of needles can then be calculated using the following equation number of needles = Co needle width Step (g) -identifying an initial position of a second fabric course of the second fabric, having a second loop size, for imparting a second pressure By default, the initial position of the second fabric course will be the next position along the body part from the first fabric course, i.e. the next course in the garment.

Step (h) -calculating a second number of needles for the second fabric course This is performed in the same manner as for step (f) above.

Step (i) -calculating the difference between first number of needles and second number of needles This is performed by subtracting the result of step (f) from the result of step (h).

Step (I) -if the difference between the first number of needles and the second number of needles is less than or equal to a threshold number, generating a set of knitting instructions (with no transition zone) The process of generating of a set of knitting instructions is explained in greater detail below. In this case, no transition zone is required as the first fabric course 15 can immediately transition to the second fabric course 17.

Step (k) -if the difference between the first number of needles and the second number of needles is greater than the threshold number, introducing, after the first fabric course 15, a transition zone 16 comprising at least a first transitionary course 16a of the first or second fabric, and shifting the initial position of second fabric course 17 to after the transition zone 16 The or each transitionary course within the transition zone 16 may comprise a single fabric course, or multiple identical fabric courses may be provided in respect of each distinct transitionary course.

Step (I) -identifying the respective circumference of the body part and respective 20 pressure for the introduced transitionary course 16a The series of circumferences (from step (b)) and the pressure required for each position along the body part (from step (d)) are fixed. Thus, shifting the position of the second fabric course 17 means it is now acting on a new circumference and required pressure. In turn, the newly-introduced transitionary course 16a is now acting on the circumference and pressure required of the initial position of the second fabric course 17. This is important to note, as in the next step the system will calculate the needles required for the first transitionary course 16a and the shifted second fabric course 17.

Step (m) -calculating an optimal number of needles for the introduced transitionary course 16a To calculate the optimal number of needles for the introduced transitionary course 16a, the first step is to calculate the number of needles for the shifted second fabric course 17 at its new circumference and required pressure. The difference between the first fabric course 15 and the shifted second fabric course 17 is the "void" the method is aiming to fill with the first transitionary course 16a. Unless the difference is only slightly greater than the threshold number (e.g. one needle greater than the threshold number, i.e. three in the presently-preferred embodiment), the number of needles in the first transitionary course 16a is set to be a step jump of the threshold number of needles (e.g. two) towards the shifted second fabric course 17.

As mentioned above, a fabric has pressure delivery characteristics dependent on yarn, knit style and loop size. Accordingly, the system may have a library of candidate fabrics. For example, it may have a collection of pressure delivery characteristics based around solely varying the loop size but keeping all the other characteristics the same. In a more advanced version, the system may take into account the scalar variable changing the loop size makes to the pressure delivery characteristics rather than having fixed data.

To calculate the best fabric to use, the system may loop through the available candidate fabrics and calculate the number of needles to deliver the required pressure on the circumference. The optimal choice of fabric for the first transitionary course 16a would be any fabric that has a step of the threshold number of needles (i.e. two in the presently-preferred embodiment) in the correct direction to reduce the gap between the first fabric course 15 and the second fabric course 17. If multiple candidate fabrics are available, the optimal choice may be selected as being the one having the closest fabric properties to the first fabric course 15.

Step (n) -calculating the difference between the number of needles of the introduced transitionary course 16a and a calculated number of needles of the second fabric course 17 in its shifted position This is performed by calculating a number of needles of the second fabric course 17 in its shifted position, and then subtracting that number from the result of step (m).

Step (o) -if the difference between the number of needles of the introduced transitionary course 16a and the number of needles of the second fabric course 17 in its shifted position is less than or equal to the threshold number, generating a set of knitting instructions for producinq the compression garment (including the transition zone 16) The process of generating of a set of knitting instructions is explained in greater detail below. In this case, a transition zone 16 is included to provide a satisfactorily smooth transition from the first fabric course 15 to the second fabric course 17. An example resulting compression garment 10 is shown in Figure 5(b), in which the second fabric course 17 is separated from the first fabric course 15 by the transition zone 16 comprising the transitionary course 16a.

Step (p) -if the difference in the number of needles between the introduced transitionary course 16a and the number of needles of the second fabric course 17 in its shifted position is still greater than the threshold number, introducing a further transitionary course 16b in the transition zone 16, shiftinq the position of the second fabric course 17 further, and repeating from step (I) above By introducing the further transitionary course 16b, there are now at least two transitionary courses, 16a and 16b, in the transition zone 16, for example as illustrated in Figure 6.

In a presently-preferred embodiment, the first transitionary course 16a is of the first fabric, at the start of the transition zone 16, adjacent to the first fabric course 15, whereas the second transitionary course 16b of the second fabric, at the end of the transition zone 16, adjacent to the second fabric course 17 in its shifted position. Optionally (see box 39 in Figure 3) the method may further comprise the system antagonistically adjusting the loop size of the first transitionary course 16a and the loop size of the second transitionary course 16b, starting from the first loop size and the second loop size respectively. Such a process is illustrated in Figure 7.

More particularly, Figure 7(a) shows the first transitionary course 16a and the second transitionary course 16b before antagonistic adjustment of the loop sizes has taken place. From Figure 7(a) it will be appreciated that the jump in number of needles between the first transitionary course 16a and the second transitionary course 16b is significantly larger than the jumps between the first fabric course 15 and the first transitionary course 16a, and between the second transitionary course 16b and the second fabric course 17, giving an uneven overall transition from the first fabric course 15 to the second fabric course 17 via the two transitionary courses 16a, 16b. However, as shown in Figure 7(b), by increasing the loop size of the first transitionary course 16a and antagonistically decreasing the loop size of the second transitionary course 16b, a more even overall transition from the first fabric course 15 to the second fabric course 17 can be obtained.

Step (o) -once sufficient transitionary courses have been provided in the transition zone 16, such that the difference in the number of needles between the introduced transitionary course (e.g. 16b) and the number of needles of the second fabric course 17 in its shifted position has become less than or equal to the threshold number, generating a set of knittinq instructions for producing the compression garment (including the transition zone 16) The process of generating of a set of knitting instructions is explained in greater detail below. In this case, a transition zone 16 is included to provide a satisfactorily smooth transition from the first fabric course 15 to the second fabric course 17. An example resulting compression garment 10 is shown in Figure 6, in which the second fabric course 17 is separated from the first fabric course 15 by the transition zone 16 comprising the first transitionary course 16a and the second transitionary course 16b.

Steps (j and (o)-generating a set of knitting instructions In steps (j) and (o) above, the system generates a set of knitting instructions for producing the compression garment (or at least part of it) from the selected materials in accordance with the representation of the body part and the specified pressure configuration, including the first fabric course 15 having the first number of needles and the second fabric course 17 having the second number of needles. In the case of step (o) applying, the knitting instructions will also include instructions to incorporate the custom-designed transition zone 16 between the first fabric course 15 and the second fabric course 17.

More particularly, a knitting pattern may be produced based on the number of needles for each representation course. An example of such a knitting pattern is represented in Figure 8, showing the first fabric 12, the second fabric 14, and the transition zone 16. The knitting pattern 40 comprises a series of lines adjacent to each other arranged in a top-to-bottom direction. Each line represents a material course which will be knitted, and may be described as a knitting course. The length of each line indicates the number of needles of the respective course. The left-to-right position of each line relative to adjacent lines indicates an offset of the courses. For example, as shown in Figure 8, all of the lines of the knitting are aligned along one side, to the left, and as such a garment knitted to according to the knitting pattern would have all courses aligned along one side. It will be appreciated that such a garment would not have shaping along this side. This may be advantageous for typical patients who have a flat portion on a lower leg, formed by the shin bone.

As initially generated, the knitting pattern may have too much variability in the number of needles, which may increase a risk of dropping stiches. In other words, the knitting pattern may be too rough. Consequently, the knitting pattern may be smoothed to reduce or prevent the dropping of stiches. The knitting pattern may be smoothed via the use of a further algorithm, which may, for example, adjust the number of needles of the lines so that each line of the smoothed knitting pattern has at least four adjacent lines having an equal or substantially equal value of needles.

However, other group numbers may be considered, for example at least two.

Alternatively, the knitting pattern may be shaped at both sides of the pattern. A garment produced by such a shaped knitting pattern may be more suited to patients who do not have a flat portion on a lower leg (for example, patients having oedema, obesity or lipoedema). Additionally, for stockings worn on an upper leg, shaping may be required. As such, a stocking may have a lower portion which is not shaped at one side, and an upper portion which is shaped at both sides.

Shaping at both sides may be conveniently provided by centre aligning the lines of the knitting profile. This provides symmetrically shaping for the garment.

However, for more accurate shaping, a plane may be defined across the associated representation. The plane extends through the interior of the representation, and is preferably normal to a front-to-back direction of the representation. The proportion of each representation course on one side of the plane may be recorded. The lines of the knitting profile may then be correspondingly aligned about a reference line. In other words, each line or knitting course of the knitting profile may have a proportion of the line or knitting course on one side of the reference line which corresponds to the proportion of the associated representation course which was on said side of the plane. As such, the knitting profile is shaped to correspond to the representation. The reference line may be considered to be internal to the knitting profile, rather than at an edge of the knitting profile.

Bespoke compression garment Thus, with reference again to Figures 5(b) and 6, the present method enables a bespoke compression garment 10 to be produced, comprising: a transition point TP at which a first fabric 12 begins a transition to a second fabric 14, wherein, at the transition point TP, a first fabric course 15 of the first fabric 14 is provided, the first fabric course 15 having a first number of needles and a first loop size, for imparting a first pressure on a first position of the body part; and a transition zone 16 after the first fabric course 15, and before a second fabric course 17 of the second fabric 14, the second fabric course 17 having a second number of needles and a second loop size, for imparting a second pressure on a second position of the body pad; wherein the transition zone 16 comprises one or more transitionary courses 16a, 16b of the first or second fabric, the or each transitionary course 16a, 16b being configured to maintain a specified pressure configuration P from the first fabric course 15 to the second fabric course 17; and wherein the number of needles of the or each transitionary course 16a, 16b is optimised to reduce the jump in number of needles between the first fabric course 15, the or each transitionary course 16a, 16b, and the second fabric course 17, by varying the loop size and/or knit style of the or each transitionary course 16a, 16b.

Worked example

The following worked example, in respect of a bespoke compression stocking, illustrates the present design method by reference to exemplary materials, dimensions and other parameters: 1. It is decided to transition from the first fabric 12 to the second fabric 14 at a point 2cm beyond the "waist" of the leg -this is the transition point TP (step (e) of the method).

2. The circumference at this point is 25cm -this is the "first circumference" at the transition point TP (step (e) of the method). 25 3. It is decided to transition from material "L16", which will be used on the foot until a course before 2cm beyond the waist of the leg, to material "M17" for the remainder of the garment. Accordingly, L16 would be the first fabric 12 and M17 would be the second fabric 14. In this example, they both use the same knit style but different loop sizes.

4. To achieve the required amount of pressure of the last L16 course, 50 needles are required (step (f) of the method).

5. The circumference for the initial second fabric course is 25.5cm (step (g) of the method).

6. To achieve the required amount of pressure for the first course of M17, 60 needles are required. A larger garment is required to deliver almost the same amount of pressure because M17 produces more pressure for the same size of garment, due to the higher stiffness of the fabric (step (h) of the method).

7. However, if we were to attempt to knit a garment with a course-to-course transition of 10 needles (the difference between 60 needles and 50 needles), it would cause serious manufacturing issues (step (i) of the method; in this example the difference is above the threshold number of two).

8. On the other hand, if we were simply to change the number of needles of either fabric, we would significantly change the amount of pressure delivered. This is not acceptable in a compression garment as it would lead to a tourniquet effect.

9. Thus, the present algorithm alters the design of the fabric by introducing a transition zone 16 (step (k) of the method) to deliver a changing amount of pressure, to lead to a smooth transition from the first fabric 12 to the second fabric 14.

10. In our example, we would want to close the gap of 10 needles to an acceptable 2 needles (the threshold number). To achieve this, we would want to increase the pressure slowly of the first fabric (L16) and decrease the pressure of the second fabric (M17). This would be done by changing the loop size of both fabrics antagonistically, i.e. increasing the loop size in respect of M17 and decreasing the loop size in respect of L16. This sets the scene for the optimal number of needles as in step (m) of the method.

11. Likewise, the change of loop size has to be done gradually as not to have a jump of greater than 2 needles between courses (again referring to the concepts in step (m) of the method).

12. To close this gap, the method introduces a first transitionary course 16a formed of the second fabric. This shifts the position of the second fabric course 17. Thus, the first transitionary course 16a now acts on the circumference of 25.5cm (step (I) of the method), as per step 5 of this worked example, and the shifted second fabric course 17 now has a circumference of 26cm in its new position.

13. The method now needs to calculate the number of needles of the first transitionary course 16a and the shifted second fabric course 17 (step (m) of the method). The first transitionary course 16a needs 52 needles and the shifted second fabric course 17 needs 61 needles. The increase of needles required on the shifted second fabric course 17 is due to a similar pressure required but larger circumference. Note the difference in needles between the first fabric course 15 and the first transitionary course 16a is equal to the threshold.

14. However, the difference between the first transitionary course 16a and the shifted second fabric course 17 (step (n) of the method) is still larger than the threshold, so an additional transitionary course 16b is required (step (p) of the method).

15. Steps 12 to 14 of this worked example are repeated until the threshold is met, and then the set of knitting instructions is generated (step (o) of the method).

It should be noted that, in this worked example, only transitionary courses of the second fabric have been introduced, but instead the transitionary courses could comprise a mixture of the first and second fabrics, with different loop sizes.

Variants In variants of the above-described method, the transition zone 16 may take the form of a transition that incorporates a change in knit style rather than a change in loop size.

Knitting the compression garment The above method, and the present disclosure more generally, are primarily directed to designing a bespoke compression garment, and therefore the method may end once the product has been designed. The above method may however continue to include the manufacture of the compression garment itself.

Thus, the above method may further comprise a step of knitting the compression garment based on the or each knitting pattern using the selected material. The bespoke compression garment may be knitted with a knitting machine.

Although the compression garment is described as knitted, it will be appreciated that similar modelling methods and processes may be applied for non-knitted garments, for example woven garments or other garment construction.

Although the method describes generating a knitting profile and knitting the garment, it will be appreciated that these steps may be excluded if only a garment modelling process is required.

Although flat knit courses are described above, it will be appreciated that helically 20 knitted courses may be designed and manufactured using a variant of the present principles. Sections of the helical course may be modelled in a similar or identical way as the representation courses described above.

A system may be provided for manufacturing a bespoke knitted compression garment. The system comprises a body part scanner for scanning the body part of the patient and producing the representation, and pressure configuration data, in other words the pressure configuration prescribed by the healthcare professional to be applied to the patient. The system further comprises material data, such as a database of characteristics of at least one material type. A processor or computer may carry out the analysis steps on the representation and produce the knitting pattern. A knitting machine may be required to knit the garment.

The words 'comprises/comprising' and the words 'having/including' when used herein with reference to the present invention are used to specify the presence of stated features, integers, steps or components, but do not preclude the presence or addition of one or more other features, integers, steps, components or groups thereof.

It is appreciated that certain features of the invention, which are, for clarity, described in the context of separate embodiments, may also be provided in combination in a single embodiment. Conversely, various features of the invention which are, for brevity, described in the context of a single embodiment, may also be provided separately or in any suitable sub-combination.

The embodiments described above are provided by way of examples only, and various other modifications will be apparent to persons skilled in the field without departing from the scope of the invention as defined herein.

Claims

CLAIMS1. A computer-implemented method of designing a bespoke compression garment, the method comprising: (a) obtaining a representation of a body part on which the compression garment is to be worn; (b) determining, from the representation, a respective series of circumferences along the body part; (c) obtaining a specified pressure configuration to be applied by the 10 compression garment on the body part; (d) determining a respective pressure for each of the series of circumferences, based on the specified pressure configuration, (e) identifying a transition point on the compression garment, at which transition point a first fabric is to begin a transition to a second fabric, the transition point corresponding to a first position along the body part having a respective first circumference, at which a respective first pressure is to be applied by the compression garment, wherein, at the transition point, a first fabric course of the first fabric is to be used, the first fabric course having a first loop size, for imparting the first pressure on the first position of the body part; (f) calculating a first number of needles required in respect of the first fabric course in order to impart the first pressure on the first position of the body part, based on the first circumference; (g) identifying an initial position of a second fabric course of the second fabric, corresponding to an initial second position along the body part having a respective second circumference at which a respective second pressure is to be applied by the compression garment, wherein, at the initial position, the second fabric course has a second loop size, for imparting the second pressure on the initial second position of the body 30 part; (h) calculating a second number of needles required in respect of the second fabric course in order to impart the respective second pressure on the initial second position of the body part, based on the second circumference; (i) calculating the difference between the first number of needles and the second number of needles; if the difference between the first number of needles and the second number of needles is less than or equal to a threshold number, (j) generating a set of knitting instructions for producing the compression garment, including the first fabric course having the first number of needles and the second fabric course in its initial position having the second number of needles; if the difference between the first number of needles and the second number of needles is greater than the threshold number, (k) introducing, after the first fabric course, a transition zone comprising at least a first transitionary course of the first or second fabric, with the initial position of the second fabric course being shifted to after the transition zone; (I) identifying the respective circumference of the body part and the respective pressure for the introduced transitionary course; (m) calculating, for the introduced transitionary course, an optimal number of needles required to impart the respective pressure on the respective circumference of the body part, whilst avoiding a jump of more than the threshold number of needles between the preceding fabric course and the introduced transitionary course, wherein the number of needles of the introduced transitionary course is optimised to reduce the jump in number of needles between the introduced transitionary course and the second fabric course in its shifted position, by varying the loop size and/or knit style of the introduced transitionary course; (n) calculating the difference between the number of needles of the introduced transitionary course and a calculated number of needles of the second fabric course in its shifted position; if the difference between the number of needles of the introduced transitionary course and the number of needles of the second fabric course in its shifted position is less than or equal to the threshold number, (o) generating a set of knitting instructions for producing the compression garment, including the first fabric course having the first number of needles, the transition zone in which the number of needles changes from the first number of needles to the second number of needles, and the second fabric course in its shifted position having the second number of needles; if the difference between the number of needles of the introduced transitionary course and the number of needles of the second fabric course in its shifted position is greater than the threshold number, (p) introducing a further transitionary course in the transition zone, shifting the position of the second fabric course further, and repeating from step (I) above.
2. The method according to claim 1, wherein the transition zone comprises: a first transitionary course of the first fabric, at the start of the transition zone, adjacent to the first fabric course; and a second transitionary course of the second fabric, at the end of the transition zone, adjacent to the second fabric course in its shifted position; and wherein the method further comprises: antagonistically adjusting the loop size of the first transitionary course and the loop size of the second transitionary course, starting from the first loop size and the second loop size respectively.
3. The method according to claim 1 or claim 2, wherein the threshold number is 20 two.
4. The method according to any preceding claim, wherein the representation of the body part comprises scan data of the body part.
5. The method according to claim 4, wherein the representation of the body part comprises 3D scan data.
6. The method according to any preceding claim; and manufacturing the compression garment by knitting the fabrics in accordance with the generated set of knitting instructions.
A compression garment manufactured by the method of claim 6.
The compression garment of claim 7, being flat knit.
9. A computer program comprising instructions which, when the program is executed by a computer processor, cause the computer processor to carry out the method of any of claims 1 to 6.
10. A bespoke compression garment comprising: a transition point at which a first fabric begins a transition to a second fabric, wherein, at the transition point, a first fabric course of the first fabric is provided, the first fabric course having a first number of needles and a first loop size, for imparting a first pressure on a first position of the body part; and a transition zone after the first fabric course, and before a second fabric course of the second fabric, the second fabric course having a second number of needles and a second loop size, for imparting a second pressure on a second position of the body part; wherein the transition zone comprises one or more transitionary courses of the first or second fabric, the or each transitionary course being configured to maintain a specified pressure configuration from the first fabric course to the second fabric course; and wherein the number of needles of the or each transitionary course is optimised to reduce the jump in number of needles between the first fabric course, the or each transitionary course, and the second fabric course, by varying the loop size and/or knit style of the or each transitionary course.