US20060181075A1

US20060181075A1 - Method for judging ski or snowboard and program for the same

Info

Publication number: US20060181075A1
Application number: US11/380,208
Authority: US
Inventors: Shigehiro Kawai
Original assignee: Japana Co Ltd
Current assignee: Japana Co Ltd
Priority date: 2004-02-10
Filing date: 2006-04-26
Publication date: 2006-08-17
Also published as: WO2005075032A1; JP2005224291A; JP4512914B2

Abstract

A program and method are used for assessing and selecting a ski or snowboard suitable for an individual skier or snowboarder. Skis and snowboards are judged as suitable for the weight and leg strength of a skier or snowboarder, and their skill level and preferred technique. Such methods may include steps of inputting the weight, the leg strength, and the skill level, determining a bending characteristic of skis or snowboards that correspond to the user's weight and leg strength, determining a torsion characteristic that corresponds to the user's skill level, and assessing and selecting a ski or snowboard suitable for those characteristics.

Description

BACKGROUND OF THE INVENTION

The invention relates to sporting goods, and in particular to methods, apparatus, and computer programs for assessing and selecting a ski or snowboard based on the weight, leg strength, skill level, and technique of a particular skier or snowboarder.
Ski boards or snowboards suitable for individual skiers or snowboarders are preferably judged and selected based on the weight and leg strength of each skier or snowboarder, his skill level and capability, his preferred technique, and other such individualized factors.
When purchasing skis or a snowboard, the customer shops for and selects a favorite ski or snowboard.
The customer has in general selected a pair of skis or a snowboard based upon his height or weight, depending upon his own intuition, and without much reliance on definite selection criteria. In many cases customers purchase skis or snowboards that a shop clerk recommends, but sometimes based simply on price or appearance. It has been difficult to reliably select and purchase skis or snowboards suitable for the physical characteristics of each skier or snowboarder and his own skill level and technique.
A method of searching for such a ski or snowboard suitable for each skier or snowboarder has been offered based on a determination of the size and flex of each part of the ski or snowboard suitable for each skier or snowboarder, based on physical information such as the age, weight, height, and leg strength of each skier or snowboarder. Such a method is described in Japanese Patent Laid-open Application 2002-312371.
However, in the above-mentioned conventional method for searching for sporting goods, the size and flex of each portion of the ski or snowboard suitable for each skier or snowboarder are determined in a standardized manner based on physical characteristics such as the age, weight, height and leg strength of each skier or snowboarder, and no consideration as to whether or not this decision matches the skill level of each skier or snowboarder.
Accordingly, in the above-mentioned conventional method for searching for sporting goods, there has been a problem in that re-investigation is required by each skier or snowboarder as to whether or not the searched-for ski or snowboard is suitable for his own individual skill level.
Furthermore, in the above-mentioned conventional method for searching for sporting goods, no consideration has been given to the torsion characteristics of skis or snowboards suitable for a given skill level for an individual skier or snowboarder.
The present invention has been made with consideration of the shortcomings of the foregoing prior art. The invention provides a method for judging and selecting skis or snowboards, and a program for accurately selecting a ski or snowboard suitable for the physical features and skill level of each skier or snowboarder.
The invention may also provide a method for judging a ski or snowboard and a program for judging a ski or snowboard that can be used in the development and design of skis or snowboards suitable for particular users.

SUMMARY OF THE INVENTION

An embodiment of the invention provides a method for judging a ski or a snowboard that allows the ski or snowboard suitable for the weight, leg strength, and level of skill of a skier or snowboarder to be judged. The method may include steps of inputting the weight, the leg strength, and the skill level of the skier or snowboarder, determining a bend characteristic of the ski or snowboard appropriate for the weight and leg strength, determining a torsion characteristic of the ski or snowboard corresponding to the skill level, and assessing and selecting a ski or snowboard suitable for the bending and torsion characteristics.
This allows for the assessment and selection of skis or snowboards suitable for a particular skier or snowboarder based upon his weight, leg strength, and individual skill level.
Such a method may include steps of storing information corresponding to a plurality of types of skis or snowboards including bending and torsion characteristics of each ski or snowboard, in a storage means, and reading out information corresponding to skis or snowboards appropriate to the bending and torsion characteristics from the storage means as steps in a method for assessing and selecting a ski or snowboard for a particular user.
Based on the weight and leg strength of each skier or snowboarder, skis or snowboards suitable for that skier or snowboarder can be judged by searching the storage means.
Methods according to the invention may include steps of obtaining a style, skill level, or technique that suits the individual taste of a skier or snowboarder, and assessing and selecting skis or snowboards suitable for that style, skill level, or technique.
This allows skis or snowboards to be assessed and selected that are suitable for a style of use appropriate to the abilities and taste of an individual skier or snowboarder.
A method according to the invention may include a step of judging as suitable a ski or snowboard that corresponds to the height, the weight, the body type, or the age of a particular skier or snowboarder.
A plurality of potentially suitable skis or snowboards may be selected and displayed.
This allows an individual skier or snowboarder to select from among this plurality of skis or snowboards a ski or snowboard suitable for himself.
A method according to the invention may include a step of displaying or notifying the user of a suitable ski or snowboard.
Methods according to the invention may include judging the ski or snowboard suitable for the weight, leg strength, and skill level of a skier or snowboarder, and a style or technique that suits the taste and abilities of the skier or snowboarder, in a system that includes board characteristic storage means for storing bending and torsion characteristics of a plurality of types of skis or snowboards, measuring means for measuring the weight and leg strength of a skier or snowboarder, input means for inputting the information related to the user's skill level or preferred technique, a bending characteristic determining means for determining bending characteristics of skis or snowboards that correspond to the weight and leg strength measured in the measuring means, and torsion characteristic determining means for determining torsion characteristics of skis or snowboards suitable for the user's skill level and technique.
A method according to the invention may include use of a program for judging and selecting a ski or snowboard suitable for the weight and leg strength of an individual skier or snowboarder, and his own skill level or technique, which includes steps of inputting the weight and leg strength, inputting the level of skiing or snowboarding skill, determining a bend characteristic of a ski or snowboard that corresponds to the weight and leg strength, determining a torsion characteristic of a ski or snowboard that corresponds to the appropriate skill level, and selecting a ski or snowboard that has suitable bending and torsion characteristics.
A method according to the invention may include steps of pre-storing a plurality of types of skis or snowboards and corresponding relationships with the bending and torsion characteristics of each ski or snowboard in a storage means, and reading information indicative of skis or snowboards that correspond to the bending and torsion characteristics from the storage means.
A method according to the invention may be one in which notification of a suitable ski or snowboard is made with a preprogrammed voice notification.
A method according to the invention may include a simulation display of a technique used by a skier or snowboarder. This may allow the skier or snowboarder to visually confirm a simulated downhill run employing the ski or snowboard judged to be suitable for that user.

DESCRIPTION OF THE FIGURES

The invention will be understood best by reference to the following detailed description of presently preferred embodiments, taken in conjunction with the appended drawings, in which:
FIG. 1 is a system for judging a ski or snowboard;
FIG. 2 is a block diagram;
FIGS. 3-8 illustrate various contents of a display;
FIG. 9 is a view illustrating a coordinate system of a ski;
FIG. 10 is an analysis view of a turn arc of the ski;
FIG. 11 shows a disposition of load sensors;
FIG. 12 is a block diagram of a leg strength measuring apparatus;
FIG. 13 shows values measured by the leg strength measuring apparatus;
FIG. 14 shows a planar distribution of load values measured by the leg strength measuring apparatus;
FIG. 15 shows a flowchart;
FIG. 16 shows a simulation of a ski run;
FIG. 17 is a view illustrating the state of having made an edging turn with the ski;
FIG. 18 is a view illustrating a radius of the turn arc at the time of the edging turn;
FIG. 19 is a view illustrating a point-by-point display of the turn;
FIG. 20 is a view illustrating the state obtained by coordinate-converting the state of FIG. 19 into one viewed obliquely from the front;
FIG. 21 is a view illustrating a relationship between the radius of the turn arc of a skiing or snowboarding method (small turn) selected by the skier or snowboarder and the judged radius of the turn arc of the ski or snowboard in which the ski or snowboard is assessed as being appropriate for the turn in question; and
FIG. 22 is a view similar to FIG. 21, but in which the ski or snowboard is judged as being inappropriate for the turn.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

As shown in FIG. 1, a system 1 for assessing and selecting a ski or snowboard includes an input means 2 for inputting information about a skier or snowboarder, and a personal computer 3 (hereinafter referred to as a PC) operable to search for a ski or snowboard suitable for the skier or snowboarder, based upon the information about the skier or snowboarder input from the input means 2.
The weight and leg strength of the skier or snowboarder, the technique used with the ski or snowboard, etc., are listed as information associated with the skier or snowboarder.
A weight and leg strength measuring apparatus 4, a keyboard 5, etc., are included in the input means 2. The PC 3 includes a PC body 6, a display 7 that functions as a peripheral device for the PC body 6, and a keyboard 5 as the input means 2.
The weight and leg strength of the skier or snowboarder are measured in the weight/leg strength measuring apparatus 4 and input into the PC 3. Furthermore, the skill level and technique of the skier or snowboarder is key-input with the keyboard 5. A method is described below for inputting the weight, leg strength, and skill level of the skier or snowboarder. As shown in FIG. 2, the PC body 6 of the PC 3 includes a CPU (not shown), a ROM (not shown) and a RAM as storage means 8. The skis or snowboards are divided into groups depending upon their bend and torsion characteristics, and information reflecting this is stored in the storage means 8.
Preloaded program software is built-in into the ROM in advance. The CPU reads out and executes the program software, with board characteristic determining means 9 and board searching means 10 arranged as shown in FIG. 2.
The board characteristic determining means 9 determines the bending characteristics of the ski or snowboard compared with the weight and leg strength of the skier or snowboarder. In particular, the board characteristic determining means 9 determines that a larger resistance against bending is required from a ski or snowboard for use by a skier or snowboarder whose weight or leg strength is high so that the skier or snowboarder applies a large load to the ski or snowboard
The board characteristic determining means 9 is further capable of comparing the torsion characteristics of the ski or snowboard to the skill level and technique of the skier or snowboarder. That is, a skier or a snowboarder has a tendency to raise the edges of the ski or snowboard, and this tendency increases along with an increase in the skier or snowboarder's level of skill. When doing so, a large torsion is applied to the ski or snowboard. The board characteristic determining means 9 determines that a ski or snowboard that offers a strong resistance against torsion is suitable for a skier or a snowboarder with a high level of skill and advanced technique.
The board searching means 10 selects skis or snowboards that have characteristics determined as appropriate by the board characteristic determining means 9. The skis or snowboards are selected by searching the information stored in the storage means 8.
Program software is preloaded into the ROM of the PC 3. The operations of the keyboard 5, the display 7, and the storage means 8 are controlled based upon this program software.
A method for inputting the skill level and technique of the skier or snowboarder using the keyboard 5 and the display 7 is described below.
The keyboard 5 and the display 7 are used in conjunction with one another to input items of information that correspond to the skill level and technique of the skier or snowboarder. An operator uses the keyboard 5 to enter information corresponding to the contents of the display 7. When the customer registration screen shown in FIG. 3 is displayed in the display 7, the predetermined items corresponding to the individual customer are key-input into blanks 11 on the customer registration screen. As this FIG. 3 illustrates, a confirmation icon 12 is clicked to confirm the information entered into the display. Clicking a reset icon 13 resets the display so that new information can be entered. Displaying a skill level image screen as shown in FIG. 4 allows the user to select an image that illustrates his own technique and enter the numeral that corresponds to that image into a blank 14. The entry is then confirmed when the user clicks on a confirmation icon 15. The information the user enters with the keyboard 5 is stored in the storage means 8 (shown in FIG. 2) of the PC 3.
FIG. 5 illustrates a series of queries to which the user provides answers regarding his skill level, preferences, and experience. These queries request information such as [Question 1: Have you participated in a skiing tournament?] and [Question 2: Have you received a qualifying test?]. Answers are selected by clicking [Yes] or [No] for each inquiry with the keyboard. Again, clicking a confirmation icon 16 confirms the information entered in response to the inquiries. Clicking a reset icon 17 resets the information so that new responses can be entered.
The skill level and technique of the individual skier or snowboarder are thereby specified by entering the number corresponding to one of the images displayed in FIG. 4, and by responding to each of the inquiries shown in FIG. 5.
FIG. 6 illustrates a display of a user's weight, leg strength, and maximum applied load, which is obtained by adding the weight and leg strength. Also displayed are bending characteristics of the ski or snowboard in response to the weight, leg strength and maximum load, the skill level of the skier or snowboarder, and the torsion characteristics of the ski or snowboard in relation to the user's skill level. Several types of skis or snowboards with appropriate bending and torsion characteristics are also displayed. FIG. 6 illustrates a case in which the user's weight is 75 kgf, his leg strength is 145 kgf, the maximum applied load (the sum of the weight and leg strength) is 220 kgf, and the bending characteristic is HARD. The user's skill level is listed as AB and the torsion characteristic as MIDDLE. Four skis or snowboards are displayed whose bending characteristics is HARD and whose torsion characteristic is MIDDLE. The bending characteristic is determined with respect to the maximum applied load. A relationship between the maximum applied load and the bending characteristic is shown in FIG. 7, but the numerical relationship between the maximum applied load and the bending characteristic can be changed as deemed appropriate.
The weight, the leg strength, and the maximum load, which is obtained by adding the weight and leg strength together, are measured with the leg strength measuring apparatus 4 (shown in FIG. 1). The bending characteristic of the ski or snowboard is determined by the board characteristic determining means 9. Information corresponding to the user's skill level is input with the keyboard 5. The torsion characteristic of the ski or snowboard is obtained by the board characteristic determining means 9 based on the skill level of the skier or snowboarder.
Clicking the details section 18 shown in FIG. 6 displays the details of a selected one of the skis and snowboards from among those that are displayed. FIG. 8 illustrates the display of characteristics of one of the skis or snowboards selected from FIG. 6. The ski or snowboard's brand, item name, and size can be displayed, along with the board's top width, waist width, tail width, side curve radius, boot center position, the weight of the ski or snowboard, and its bending and torsion distributions. The shoulder width Bs, waist width Bw, tail width Bh, and boot center position B of the ski and snowboard are illustrated in FIG. 9.
Clicking the confirmation icon 19 shown in FIG. 8, confirms the customer's selection of the ski or snowboard whose details are displayed in FIG. 8. Clicking the reset icon 20 rejects the selection so that another ski or snowboard might be selected. The configuration of the weight and leg strength measuring apparatus 4 shown in FIG. 1, and a method for measuring and entering the weight and leg strength of the skier or snowboarder using this weight and leg strength measuring apparatus 4 are described below.
As shown in FIG. 1, a leg strength measuring apparatus 4 includes a measurer 31 and a personal computer (hereinafter, referred to as a PC) 32. The measurer 31 is an appliance for measuring a load such as the weight of a person to be measured. The PC 32 is for inputting values measured by the measurer 31, and for executing a process for calculating the leg strength of the person, the planar distribution of the load, etc. The measurer 31 includes a base stand 33, with two footplates 34 and 35 provided on the base stand 33 in parallel to one another. The two footplates 34 and 35 are provided separately so that the person whose leg strength is measured steps on them individually with his left and right feet. Three load sensors (load cells) 36, 37, and 38 are located between one footplate 34 and the base stand 33. Another three load sensors 39, 40, and 41 are located between the other footplate 35 and the base stand 33. Each of the sensors 36 to 41 detects a vertical load applied to one of the footplates 34 and 35.
The base stand 33 may be formed in any desired shape so long as it supports the footplates 34 and 35. It may, for example, take the form of a four-cornered framework with four supporting bodies 42, 43, 44, and 45 assembled in a square. It may also include an auxiliary body 46 positioned in parallel with the supporting body 43. Casters 47 at the four corners of the base stand 33 allow the base stand 33 to be moved and positioned as desired. In a base stand 33 of this type, one footplate 34 spans the gap between the supporting body 45 and the auxiliary body 46, with the other footplate 35 spanning the gap between the supporting body 43 and the supporting body 45.
The footplates 34 and 35 may be long and narrow. Each of the footplates 34 and 35 is a rigid member that is not easily bent or deflected so that loads applied to the footplates 34 and 35 will be efficiently transmitted to the load sensors 36 to 41. A sensor fixing section 48 that is wider than the first footplate 34 is located beneath one tip of the first footplate 34, with load sensors 36 and 37 located at the sensor fixing section 48. Another load sensor 38 is provided at the opposite end of the footplate 34.
Another sensor fixing section 49 that is wider than the second footplate 35 is located under one end of the second footplate 35. Load sensors 39 and 40 are secured to the sensor fixing section 49, with a further load sensor 41 located at the opposite end of this second footplate 35. The assembly of the sensor fixing section 48 and the three load sensors 36 to 38 in combination with one footplate 34 comprises a first footplate unit 50. A second footplate unit 51 includes the sensor fixing section 49 and the three load sensors 39 to 41 in combination with the other footplate 35. As FIG. 1 and FIG. 11 illustrate, the load sensor 38 is positioned on an axial line L1 of one footplate 34, with load sensors 36 and 37 placed at positions that form an isosceles triangle with the load sensor 38. Load sensor 41 is positioned on an axial line L2 of the other footplate 35, with load sensors 39 and 40 located at positions that form an isosceles triangle with the load sensor 41.
The first footplate unit 50 forms a span between the supporting body 45 and the auxiliary body 46. This footplate unit 50 is fixed to the auxiliary body 46 and the supporting body 45 with the two load sensors 36 and 37 of the footplate unit 50 located between the sensor fixing section 48 and the auxiliary body 46, and with the load sensor 38 located between the footplate 34 and the supporting body 45.
The other footplate unit 51 spans the gap between the supporting body 43 and the supporting body 45. This footplate unit 51 can be made movable along the supporting body 43 and supporting body 45. Making moving bodies 52 and 53 movable along supporting bodies 43 and 45 while the two ends of the other footplate unit 50 remain fixed in place enables the second footplate unit 51 to be moved toward and away from the first footplate unit 50 along the length of the two supporting bodies 43 and 45. This makes it possible to adjust the separation distance between the two footplate units 50 and 51 as desired.
As FIG. 1 illustrates, the moving bodies 52 and 53 may be formed, for example, with a generally C-shaped cross-section, with an opening side 52 a of the moving body 52 place over the supporting body 43 and an opening side 53 a of the other moving body 53 fitted over the supporting body 45. The moving bodies 52 and 53 are thus made movable along the length of the two supporting bodies 43 and 45. One end of the second footplate unit 51 is mounted on the moving body 52 with the two load sensors 39 and 40 positioned between the sensor fitting section 49 and the moving body 52. The other end of this footplate unit 51 is mounted on the moving body 53 with the load sensor 41 located between the footplate 35 and the moving body 53.
The moving bodies 52 and 53 are bored to receive screws 54, with elongate holes 55 provided along the length of the supporting bodies 43 and 45. The screws 54 are tightened with nuts (not shown) against the peripheral rim of the elongate hole 55. This allows the moving bodies 52 and 53 to be positioned as desired and secured in place on the supporting bodies 43 and 45.
The moving bodies 52 and 53 and the screws 54 thus serve as a gap adjustment means for adjusting the separation gap between the footplates 34 and 35.
All of the load sensors 36 to 41 in both of the footplate units 50 and 51 measure the loads applied to the footplates 34 and 35 at an identical sampling interval.
A handrail 56 is fixed to the supporting body 42. Opposite ends of another handrail 57 are fixed to the moving bodies 43 and 45, thereby enabling this second handrail 57 to move together with the second footplate unit 51 and the moving bodies 52 and 53. Providing a grip made of rubber, etc., on both of the handrails 56 and 57 allows for easy gripping. Furthermore, as shown by a single broken line in FIG. 1, an opener/closer 56 a may be provided in one portion of the handrail 56 on the fixed side to allow a person to pass through the handrail. A step S may also be provided to enable the person to easily mount the footplates 34 and 35.
As shown in FIG. 12, the PC 32 includes a keyboard 58 as an input means, a display 59 as a display means, a CPU 60, RAM as a storage means 61, a ROM 62, a leg strength calculating means 63, and a load distribution analyzing means 64.
The storage means 61 is operable to store a series of values measured by the load sensors 36 to 41. Specifically, when a person, having stepped onto the footplates 34 and 35, flexes and extends his knees twice by way of experiment, the values measured in the measurer 31 fluctuate as shown in FIG. 13. The storage means 61 stores the series of measured values.
The leg strength calculating means 63 computes the leg strength of the person, as shown in FIG. 13, by subtracting the person's weight from the maximum load the person applies while bending and flexing his knees on the apparatus. In the example shown in FIG. 13, the maximum load is 220 kgf and the weight is 75 kgf, whereby the leg strength of the person is determined to be 145 kgf.
The load distribution analyzing means 64 analyzes the state of the gravity center distribution of the applied loads, based upon the measured values stored in the storage means 61, i.e. the values measured by each of the load sensors 36 to 41. One example of the state of the gravity center distribution of the loads obtained by the load distribution analyzing means 64 is shown in FIG. 14, in which each point indicates the gravity center position of the applied load at one particular moment. FIG. 14 thus illustrates the gravity center positions of the loads obtained at a pre-determined sampling interval over a pre-determined time, with the result indicated by a plurality of points. The method used to determine the state of the gravity center distribution of the loads will now be described. An X-coordinate (XG) of the gravity center of the load at each moment is obtained using numerical formula 1, and a Y-coordinate (YG) is obtained with numerical formula 2. The overall load is obtained with numerical formula 3.
XG=(f1−f2)a/F [Numerical formula 1]
YG=(f1+f2−f3)b/F [Numerical formula 2]
F=f1+f2+f3 [Numerical formula 3]
As FIG. 11 illustrates, f1 is the measured value of the load sensor 37 or 40, f2 is the measured value of the load sensor 36 or 39, and f3 is the measured value of the load sensor 38 or 41. In FIG. 14, a Y-axis is defined along the axial center L1 of the footplate 34 or the axial center L2 of the footplate 35, and an X-axis defined so that it passes through a center Q of the footplate 34 or 35 at right angles to the Y-axis.
Next, a method will be described for making a linear approximation of the change in the gravity center distribution of the loads, which have been obtained by the load distribution analyzing means 64, over a period of time. This linear approximation is made with a least-squares method.
The least-squares method is expressed by numerical formula 4.
Y=cX+d [Numerical formula 4]
The slope c of the straight line is obtained by numerical formula 5. $\begin{matrix} c = (\sum_{i = 1}^{n} XiYi - n < X > < Y >) / \sum_{i = 1}^{n} {Xi}^{2} - n < X >^{2}) & [Numerical formula 5] \end{matrix}$
The intersection d of the straight line is obtained by numerical formula 6.
d=<Y>−c<X> [Numerical formula 6]
In these formulae, <X> indicates an average coordinate of the X-coordinates at a plurality of measured load points, and <Y> indicates an average coordinate of the Y-coordinates at the plurality of measured load points. The approximate straight lines obtained in such a manner are displayed as L3 and L4 in FIG. 14. The leg length calculating means 63 and the load distribution analyzing means 64 may be configured to operate based on program software pre-stored in the ROM.
The display means 59 displays the values measured in the load sensors 36 to 41 on a graph as shown in FIG. 13, and also displays the distribution of the loads analyzed in the load distribution analyzing means 64 as shown in FIG. 14.
A program for judging and selecting a ski or snowboard suitable for the weight and leg strength of an individual skier or snowboarder, and/or his skill level and technique will be described with reference to FIG. 15. The process involves not only employment of the system for judging a ski or snowboard arranged as mentioned earlier but also execution of the following process based upon the program for judging a ski or snowboard pre-stored in the ROM. First, several types of skis or snowboards and the bending and torsion characteristics of each ski and snowboard are pre-stored in the storage means 8 in a step S1. Next, in step S2, the weight and leg strength of the skier or snowboarder and/or his skill level and technique are input using the leg strength measuring apparatus 4 or the keyboard 5 as the input means 2.
Next, in step S3, the bending or torsion characteristics of a ski or snowboard suitable for the weight and leg strength of the skier or snowboarder and/or his skill level and technique are determined. After that, a ski or a snowboard corresponding to the bending or torsion characteristic determined in step S3 is assessed and selected.
Next, information corresponding to the ski or snowboard selected in step S4 is read out from the storage means 8, and is displayed to the user in step S6.
FIG. 16 shows a simulation of a ski or snowboard run. The simulation is generated by employing the selected ski or snowboard, based upon the weight, leg strength, or skill level of the skier or snowboarder as mentioned above. To display this simulation, it is necessary first to obtain a radius R of a turn arc, based upon a length, a side curve, etc., of the selected ski or snowboard.
The technique for obtaining the radius of the turn arc for the selected ski or snowboard will be described below in conjunction with FIG. 9, FIG. 10, FIG. 17, and FIG. 18.
First, and as shown in FIG. 9, an X-axis is defined in the longitudinal direction of the ski, with the Y-axis perpendicular to it across the ski's width. The ski's tail width (at the portion of the ski that has the greatest width in the ski's rear half), the waist width (the portion having the most narrow width in the ski's middle), and the shoulder width (the portion with the greatest width at the front half of the ski) are assumed to be Bh, Bw, and Bs respectively. Furthermore, the lengths from the rear end of the ski to each of these locations are assumed to be Lh, Lw, and Ls respectively. Assuming the points on the side curve of the ski at the tail, the waist, and the shoulder to be A, B and C, it follows that these coordinates are expressed by A (Lh, Bh/2), B (Lw, Bw/2) and C (Ls, Bs/2). Furthermore, an intersection point between a straight line AC and a perpendicular from the point B to the straight line AC is assumed to be D, and the distance between B and D to be Sc. In addition, the length of CE of a right-angled triangle ACE with a hypotenuse in the straight line AC is assumed to be Z and ∠CAE (included angle) to be α (alpha).
Suppose that upon edging with the ski, the ski rotates about an axis in the straight line AC (see FIG. 17, in which the edging angle is assumed to be θ). Next, suppose that ski is pressed down perpendicularly at point B against the snow (in the XY plane). That is, point B is projected as B′. Suppose that an arc AB′C formed in such a manner is a turn arc, and a curvature radius of the circular arc that passes the points A, B′ and C is the radius R of the turn arc at the time of the edging (where it is supposed that the positions of point A and point B are unchanged). According to these suppositions, the radius R of the turn arc can be obtained with the following procedure. First, as shown in FIG. 18, consider a coordinate form with an origin at point A, and with the X-axis in the straight line AC. Assume the coordinates of the points A, B′ and C to be (X1, Y1), (X2, Y2), and (X3, Y3) respectively, then the general numerical formula of the circle that passes through these three points is given by numerical formula 7.
(X−S)²+(Y−t)² =R ² [Numerical formula 7]
A central coordinate (S, t) of the circular arc that passes three points A, B′ and C is obtained from numerical formula 8.
(S,t)=(X ₃/2,(X ₂ ² −X ₂ X ₃ +Y ₂ ²)/(2Y ₂)) [Numerical formula 8]
Furthermore, the radius R of the circular arc is obtained by a numerical formula 9.
R=√{square root over ((X ₃/2)²+[(X ₂ ² −X ₂ X ₃ +Y ₂ ²)/(2Y ₂)²]²)} [Numerical formula 9]
Assuming the number of turns made when the skier has traveled over a distance of 100 m in the X direction to be T, then the radius R can be obtained by T=100/2R.
An XY coordinate form system is employed when displaying a turn locus, as shown in FIG. 19. A ski turn that transitions from a left turn to a right turn can be displayed using the following general expression with the edging angle, the widths of the three principal points of the ski, and the radius R of the turn arc calculated from their positions. When a numerical value K that corresponds to a direction of the ski is odd, it indicates a left turn; and when the numerical value K is even, it indicates a right turn.
K=1,3,5,7 . . .
X=[(2K−1)−cos θ_t ]R
Y=−R sin θ _t
K=2,4,6,8 . . .
X=[(2K−1)−cos θ_t ]R
Y=R sin θ_t [Numerical formula 10]
As FIG. 19 illustrates, displaying the foregoing X and Y points enables a stationary image of a simulated run to be displayed.
Additionally, and as shown in FIG. 6, a classification of a large turn, a middle turn and a small turn may be input, depending on the taste of the skier or snowboarder. The classification of the large, middle, and small turns is added between the steps S2 and S3 in the flowchart shown in FIG. 15. As is mentioned above, when the ski or snowboard judged to be suitable for an individual skier or snowboarder is suitable for the large turn, the middle turn, or the small turn selected according to the taste of each skier or snowboarder, its effect is displayed. When it is not suitable, on the other hand, that assessment may be displayed too. For example, FIG. 21 illustrates a display in which the radius of the turn arc of the ski or snowboard judged to be suitable for an individual skier or snowboarder is included in a range of small turns and is thus suitable for the small turn, as is shown by a point in FIG. 21. In FIG. 22, on the other hand, the fact that the radius of the turn arc of the ski or snowboard judged to be suitable for the skier or snowboarder is not included in the range of the small turns is displayed by displaying an upper limit of the range of the small turns with a black indicator, thereby indicating that the radius exceeds the upper limit.
In the above embodiment illustrated in FIG. 1, the PC 32 for obtaining the weight/leg strength and the maximum load of the skier or snowboarder, and the PC 3 constituting the board characteristic determining means 9 and the board searching means 10 are provided as separate elements. They may, however, be provided as a single PC configured to serve the functions of both of these two PCs.
In the above embodiment, the ski or snowboard suitable for the weight, the leg strength, and the skill level of the skier or snowboarder is judged. A ski or snowboard suitable for an individual skier or snowboarder may also be judged by considering the technique that suits the taste of the skier or snowboarder, his height, his weight or body type, or his age.
Providing a fixing section for fixing the ski or snowboard boots onto the footplates 34 and 35 and measuring the load while the person is wearing the ski or snowboard boots enables the leg strength, etc. to be measured in a situation closer to the actual situation encountered in skiing or snowboarding. Furthermore, the person may stand on the footplates 34 and 35 to measure the load while having put on the ski or snowboard boots, and in addition to that, while wearing the ski or snowboard itself.
The footplates 34 and 35 may be provided horizontally. Placing the footplates 34 and 35 in a state where they are inclined front-to-back or left-and-right with their centers in the axial centers L1 and L2 of the footplates 34 and 35 makes it possible to measure the leg strength of the person and the gravity center distribution in a state more closely representative of actual skiing or snowboarding, including a state of so-called tiptoe raising or lowering, or a state of turning left and right, simulated while the person is standing on the footplates 5 and 6.

Claims

1. A method for judging a ski or snowboard in which the ski or snowboard suitable for a weight and leg strength of a skier or snowboarder, and a skill level thereof is judged, the method for judging a ski or snowboard comprising the steps of:

obtaining the weight and leg strength, and the level of skiing or snowboarding skill;

determining a bend characteristic of the ski or snowboard corresponding to the weight and leg strength;

determining a torsion characteristic of the ski or snowboard corresponding to the skill level; and

selecting a ski or snowboard suitable for the bending and torsion characteristics.

2. The method for judging a ski or snowboard according to claim 1, comprising the steps of:

storing in a storage means a plurality of types of skis or snowboards, and a correspondence relation with the bending and torsion characteristics of each ski or snowboard; and

reading out the ski or snowboard corresponding to the bending and torsion characteristics from the storage means.

3. The method for judging a ski or snowboard according to claim 1, further comprising the steps of:

obtaining a usage style that suits a taste of the skier or snowboarder; and

selecting a ski or snowboard suitable for the usage style.

4. The method for judging a ski or snowboard according to claim 1, further comprising a step of judging a suitable ski or snowboard that corresponds to at least one of the height, weight, body type, and age of the skier or snowboarder.

5. The method for judging a ski or snowboard according to claim 1, comprising a step of reading out a plurality of candidates for suitable skis or snowboards.

6. The method for judging a ski or snowboard according to claim 1, comprising of a step of notifying the skier or snowboarder of the determined ski or snowboard.

7. The method for judging a ski or snowboard according to claim 6, wherein the notification includes a display.

8. A method for judging a ski or snowboard, wherein a ski or snowboard suitable for the weight, leg strength, a skill level of a skier or snowboarder, and a technique that suits the skier or snowboarder's taste is judged using a system for judging a ski or snowboard, the system for judging a ski or snowboard comprising:

a board characteristic storage means configured to store bending and torsion characteristics of a plurality of types of skis or snowboards;

a measuring means configured to measure the weight and leg strength of a skier or snowboarder;

an input means configured to input a skill level of skiing or snowboarding for the skier or snowboarder;

an input means configured to input a usage technique that suits the taste of a skier or snowboarder;

a bending characteristic determining means configured to determine a bending characteristic of a ski or snowboard corresponding to the weight and leg strength measured in the measuring means; and

a torsion characteristic determining means configured to determine a torsion characteristic of a ski or snowboard corresponding to at least one of the skill level and usage technique.

9. A method for judging a ski or snowboard suitable for the weight, leg strength, and skill level of a skier or snowboarder, the method comprising the steps of:

inputting the weight and leg strength;

inputting the skill level;

judging the ski or snowboard suitable for the bending and torsion characteristics.

10. The method for judging a ski or snowboard according to claim 9, and further comprising steps of pre-storing a plurality of types of skis or snowboards, and a correspondence relation with the bending and torsion characteristics of each ski or snowboard in a storage means; and

reading out a ski or snowboard corresponding to the bending and torsion characteristics from the storage means.

11. The method for judging a ski or snowboard according to claim 9, and further comprising a step of inputting a usage technique that suits the taste of the skier or snowboarder, and further comprising a step of judging the ski or snowboard suitable for usage technique.

12. The method for judging a ski or snowboard according to claim 9, and further comprising a step of judging a suitable ski or snowboard that corresponds to at least one of the height, weight, body type, and age of the skier or snowboarder.

13. The method for judging a ski or snowboard according to claim 9, wherein a plurality of candidates for suitable skis or snowboards are read out in the step of reading out the ski or snowboard corresponding to the bending and torsion characteristics from the storage means.

14. The method for judging a ski or snowboard according to claim 9, wherein the judged ski or snowboard is notified to the skier or snowboarder.

15. The method for judging a ski or snowboard according to claim 14, wherein the notification is made with a display.

16. The method for judging a ski or snowboard according to claim 14, wherein the notification is made with a voice notification.

17. The method for judging a ski or snowboard according to claim 1, wherein the ski or snowboard judged to be suitable for the skier or snowboarder is employed to make a simulation display of a ski or snowboard run for the skier or snowboarder.

18. The method for judging a ski or snowboard according to claim 9, wherein the ski or snowboard judged to be suitable for the skier or snowboarder is employed to make a simulation display of a downhill run for the skier or snowboarder.