EP3513847A1

EP3513847A1 - Base plate for a ski

Info

Publication number: EP3513847A1
Application number: EP19000004.2A
Authority: EP
Inventors: Anton UMEK; Vinko Avgustin; Anton KOS; Samo Mohoric
Original assignee: Elan doo
Current assignee: Elan doo
Priority date: 2018-01-19
Filing date: 2019-01-08
Publication date: 2019-07-24
Anticipated expiration: 2039-01-08
Also published as: SI3513847T1; SI25583A; EP3513847B1

Abstract

Base plate (50, 60) for a ski (2) configured to receive a ski binding, wherein the base plate comprises a central stiff portion (3) with fastening holes for fastening the ski binding, a first fastening portion (4) moulded to one end of the central stiff portion (3), and a second fastening portion (5) moulded to the other end of the central stiff portion (3), wherein the first fastening portion comprises a transversal groove (13) arranged on the upper ski-distant surface and extending along the central stiff portion, two measuring prongs (6.1, 6.2) distanced by a separating groove (8), two sensors (11) for the measurement of mechanical stress arranged on the bottom surface of the measuring prong in the area of the transversal groove (13), wherein the second fastening portion (5) comprises a transversal groove (13) arranged on the upper surface and extending along the central stiff portion (3), at least one measuring prong (7), at least one sensor (11) for the measurement of mechanical stress arranged on the bottom surface of the measuring prong (7) in the area of the transversal groove (13), wherein each transversal groove (13) functions as a weakening spot of mechanical stresses.

Description

Object of Invention

The object of the invention relates to the field of skis, particularly to the field of a base plate of a ski that is mounted to the ski or integrated therein, to a ski provided with such a base plate, to a measuring system, of which a ski with such a base plate is part of.

Technical Problem

The technical problem is how to configure a base plate of a ski that is mountable to a ski or integrated therein and that will not only allow known functions such as lifting a ski boot from a snow surface, damping of vibrations or preventing transfer of vibrations from the ski to a skier's foot, but will also allow direct and real-time detection and measurement of stresses and forces that appear in a certain part of a ski and result from a skier's skiing technique. The configuration of the base plate must meet the requirements of stability and safety and allow for the arrangement of a ski binding. The base plate of the invention must be configured in a way to allow measurements of ski loads during skiing technique execution without making skiing technique execution more difficult or anyhow obstructed.

Prior Art

To properly execute a skiing technique, in particular carving technique, it is important that each ski is properly loaded. The desired load of a ski depends on the technique and skier's demands, depending on whether the skier is a beginner, a recreational skier or a competitive skier. The load of a ski depends on the skier's body balance point, his bending forward, backward, sideward with respect to the ski. To execute a turn, a skier loads each ski by way of a boot, a ski binding and a base plate, while the turn should be as ideal as possible based on his requirements. The execution of a turn depends on a proper load of each ski. The proper loading and consequently proper execution of the technique is influenced by both the skier's skills and the ski. The skis differ among each other by their construction, consequently by the properties and the forces required to execute a proper technique.
A proper load of a ski resulting from the skier acting with a certain force on each ski is reflected in the execution of a turn and also depends on the skier's skills. The assessment of the proper load is very subjective and depends on the skier's skills, an external observer, such as a teacher/trainer who gives the skier his subjective assessment on the execution of the technique by observing and/or recording. A proper execution of a technique is important not only in the learning phase but also in recreational and competitive skiing.
A skier should get an as objective assessment of his skiing technique execution as possible, this is why devices have been developed that detect and measure, by way of motion sensors, the position of a skier's body with respect to the skis and/or snow ground, velocities and accelerations as a function of time and in real time. Such devices are normally arranged on a skier on different parts of his body or on his ski boots. By using an adequate algorithm, the measured values and biometric properties of the skier are then converted to forces, with which a skier acts on the ski by way of his ski boots and ski bindings.
One of such solutions is disclosed in US2014244071 (Stanislaw Czaja et al. ). The system of skiing control is carried out by a plurality of sensors arranged on the skier, for instance in the areas of his knees, hips, shoulders. The motion sensors perform measurements of current vectors in x/y/z axes and transmit them via wireless connection to a mobile terminal with an adequate application. The measured values and the skier's previously measured biometric parameters are adequately assessed, the result being the forces that are exerted on the skier and the skiing equipment in a certain moment. The measured values can be transmitted via wireless connections and stored in a memory unit for subsequent assessment and analysis. Said skier's measurements and biometric parameters serve as a basis to calculate the forces that are exerted on the skier and the forces, with which the skier acts on the ski.
A drawback of the data thuso obtained lies in the fact that the values of the forces are not the actual forces measured in the ski but a result of the computation of the measured values. The measuring devices are arranged on the skier or his ski boot and not directly on the ski.
US20160375346 A1 (Stanislaw Czaja et al. ) discloses a device embedded in a ski boot insole. By way of motion and force sensors it measures the pressure in the toe, middle and heel parts of the insole caused by the skier with his foot depending on the current body position on a special extra insole in the ski boot while executing skiing. The measured values serve as a basis to determine skier's orientation and motion at a given moment by way of a special application. The obtained values of the force exerted by the skier's foot on certain spots of the extra insole within the ski boot are then applied on the ski. The disclosed device does not provide for direct measurement of the force within the ski that is caused by the skier while executing a skiing technique. The force within the ski is computed on the basis of the measurement of the forces exerted by the skier's foot on the ski boot sole and then transferred through the front and back ski binding to the ski.
US2014244071 A1 with the filing number US2014065060 (Stanislaw Czaja et al. ) discloses a device embedded in the front part of each ski, yet intended to detect and measure vibrations within a ski. The configuration of the device does not allow measurement of the forces within the ski, which result from the skier acting on the ski.
None of the indicated solutions allows for direct measurement of the forces in a ski, even less the measurement of the distribution of forces in various parts of the ski. The main challenge is a technical execution of a direct measurement of the distribution of forces, with which the skier acts on each ski separately via his ski boot.

Solution to the Technical Problem

The technical problem is solved by a base plate moulded at a distance to a ski's upper surface distant from the base in its central portion or embedded within the ski, said plate being shiftable in the longitudinal axis of the ski, prevented from shifting perpendicularly to the longitudinal axis of the ski and configured to receive a front and/or rear ski binding, wherein the base plate comprises a central stiff portion comprising fastening holes for fastening the front and/or rear ski bindings by way of known fastening elements to the base plate, a first fastening portion moulded to one end of the central stiff portion, in which two first fastening support elements for fastening the base plate to the ski are arranged, and a second fastening portion moulded at the opposite end of the central stiff portion, in which at least one second fastening support element for fastening the base plate to the ski is arranged, wherein the first fastening portion of the base plate is configured as a measuring portion comprising two measuring prongs, in which there are arranged the first fastening support elements, a transversal groove arranged on the ski distal upper surface and extending along the central stiff portion of the base plate, and at least one stress measuring sensor arranged on the ski proximal bottom surface of each prong in the area of the transversal groove, wherein the second fastening portion of the base plate is configured as a measuring portion comprising at least one measuring prong, in which there are centrally arranged a rear fastening support element, a transversal groove arranged on the ski distal upper surface and extending along the central stiff portion, and at least one stress measuring sensor arranged on the ski proximal bottom surface of each prong in the area of the transversal groove, wherein each transversal groove causes an increase in the mechanical stress within the prong.
The second fastening portion comprises two measuring prongs distanced by a separating groove, and two sensors for the measurement of mechanical stress arranged on the ski proximal bottom surface of each measuring prong in the area of the transversal groove. The transversal groove extends along the entire width of the front and rear fastening portions. The separating groove extends longitudinally along the base plate over the entire portion of the first and second fastening portions. A sensor is arranged in a seat located in the area below the transversal groove. The central stiff portion has a seat, in which a microcontroller for measuring mechanical stress is arranged. Two base plates form an assembly that can comprise a housing portion, in which a microcontroller is arranged.
The base plate of the invention is moulded to a ski or embedded into a ski. A ski can comprise two base plates of the invention. A ski can comprise a base plate assembly of the invention.
The force, with which the skier acts on each ski, is transferred via a ski boot to the front and rear ski bindings and further to the base plate which is at a distance moulded to the upper ski base distal surface. The magnitude of the force transferred to the front and/or rear ski binding depends on the skier's current balance point, his tilt with respect to each ski or the ground. In the event when the skier is off balance, a force of different sizes is transferred from the front and rear ski bindings to the first and second fastening portions of the base plate, said force causing various deformations of the base plate and consequently various internal mechanical stresses. The mechanical stresses are detected and measured by the sensor preferably arranged on the bottom, ski proximal surface of the base plate in the vicinity of each fastening support element and in the area of the transversal groove. The transversal groove formed in each fastening portion of the base plate in its upper or bottom surface and extending at the end of the central stiff portion of the base plate causes a reduced mechanical stress of the fastening portion in this section. This results in increased deformations in the area of the groove and consequently increased mechanical stresses that go beyond the mechanical stresses in the adjacent area in the central portion. The transversal groove functions as an amplifier of dilatations on the spots where the sensors are fastened. The forces of various magnitudes that are exerted on an individual fastening support element as a result of the imbalance of the skier's balance cause the mechanical stresses of different magnitudes that are detected by each measuring sensor. The measured values and their differences are indicative of the precise load of the ski in a portion as a function of the skier acting on the ski.
The sensors transmit the measured value in the form of an adequately assessed signal to a controller arranged in the central stiff portion, wherefrom it is forwarded via a communication unit, preferably wirelessly, to a receiving unit with an adequate application for data processing. This receiving unit can be for instance a smart phone arranged anywhere on the skier or any other device capable of wirelessly receiving a signal and evaluating it in an adequate application. The measured and evaluated signals can be stored in such a device, forwarded to a stationary processing unit for subsequent processing, forwarded in an adequate visual or acoustic interpretation directly after the measurement back to the skier so that the latter can immediately correct his skiing technique.
The base plate is configured to support the front and/or rear ski bindings. The base plate is provided in the first fastening portion with two measuring prongs each having one measuring sensor and in the second fastening portion with at least one measuring prong, wherein each measuring prong is provided with one measuring sensor. More precise measurements are provided for by the base plate which has two measuring prongs with the measuring sensors also in the second fastening portion.
In cases where there is a need for a more precise distribution of loads on the ski, in particular when competitive skiers are in question, two base plates are used. They are longitudinally arranged on the ski at a mutual distance, such that one base plate supports the front ski binding and the second base plate supports the rear ski binding. Each base plate configured to receive a ski binding is moulded at a space to a ski's upper surface distant from the base or embedded within the ski, said plate being shiftable in the longitudinal axis of the ski and prevented from shifting perpendicularly to the longitudinal axis of the ski. The number of sensors integrated in each base plate depends on the measuring prongs or the number of fastening support elements in each fastening portion. The first fastening portion of each base plate has two measuring prongs, the second fastening portion of the base plate has at least one measuring prong, preferably two measuring prongs. Such measurements provide for precise measurements of the loads of the ski in the area of the front ski binding or the rear ski binding.
The base plate of the invention and an adequate evaluation of the measured values allow for a very precise assessment of the skier's position on a ski, an assessment of the force, with which he acts on each ski, the force, with which he acts on each edge of each ski in a certain moment of skiing.
The measured values are immediately transmitted over a wireless connection to a processing unit that uses an adequate application to adequately evaluate the measured values and to compare same with the previously entered optimal values. The evaluated signal values are forwarded to the skier in an acoustic, visual or other form by means of any known device for displaying signals as early as during a turn execution or/and are stored in a remote user interface for subsequent processing.
The base plate of the invention is suitable both for the beginners, because it allows for an immediate elimination of errors, and experienced skiers or competitive skiers so that they can come closest to the optimal load of the ski in a certain turn without losing the speed of skiing. Moreover, the base plate of the invention can also be used in selecting the most optimal ski with respect to its characteristics. Importantly, when skiing, the skier should consume as little energy as possible, this is why he needs an adequate ski type that also depends on his way of skiing. Based on the measurements of the load of the ski and the execution of the skiing technique, the base plate of the invention is used to determine a ski that will be the most suitable for the skier depending on its properties.
The base plate of the invention can be modified in a way to allow mounting to a snowboard as well, wherein such a base plate preserves the essential characteristics of the invention.
The base plate of the invention will be described hereinbelow in more detail by way of an embodiment and drawings representing in

Fig. 1 a base plate with three measuring spots
Fig. 2 a second embodiment of the base plate with four measuring spots
Fig. 3 a ski-mounted base plate from Fig. 1
Fig. 4 a ski-mounted base plate from Fig. 2

A base plate 50 of the invention that is fundamentally meant to receive a ski binding, a front and/or rear ski binding, is moulded to a ski 2 in its central portion on its upper base-distant surface or embedded within the ski. The base plate 50 comprises a central stiff portion 3 comprising fastening holes for fastening the front and/or rear ski bindings by way of known fastening elements to the base plate, a first fastening portion 4 moulded to one end of the central stiff portion 3, and a second fastening portion 5 moulded to the other end of the central stiff portion 3. The first fastening portion 4 comprises two measuring prongs 6.1, 6.2 spaced apart by a separating groove 8. The separating groove 8 extends longitudinally along the base plate 50 over the entire portion of the first fastening portion 4. Each measuring prong 6.1, 6.2 of the first fastening portion 4 is provided with a longitudinal hole 22.1, 22.2 for the reception of a support fastening element 9.1, 9.2 for fastening the first fastening portion 4 or the base plate 50 to the ski 2. The longitudinal hole 22.1, 22.2 and the support fastening element 9.1, 9.2, which is executed as a screw with a spacer in this embodiment, form a sliding support to the base plate 50, wherewith the occurrence of shear forces in this support is prevented. The base plate 50 is fixed to the ski 2 with the second fastening portion 5. The second fastening portion 5 comprises a measuring prong 7 provided with a centrally formed longitudinal hole 23 for the reception of a support fastening element 10 for fastening the second fastening portion 5 or the base plate 50 to the ski 2. The hole 23 and the support fastening element 10, which is executed as a screw with a spacer in this embodiment, form a fixed support to the base plate 50.
The force, with which the skier acts on the ski 2, is transferred via the central stiff portion 3 of the base plate 50 as a function of the skier's balance position to the first fastening portion 4 and the second fastening portion 5 and creates mechanical stresses in each measuring prong 6.1, 6.2, 7. On the upper surface of the first 4 and second fastening portions 5 there is arranged a transversal groove 13 extending over the entire width of the first 4 and second fastening portions 5 and substantially neighbouring each end of the central stiff portion 3. The transversal groove 13 functions as a weakening spot with mechanical stresses of higher magnitudes. At the bottom side of each measuring prong 6.1, 6.2, 7 in the area below the transversal groove 13, there is a seat 12, in which two sensors 11 for measuring mechanical stress are arranged. The sensors 11, which are the sensors for measuring mechanical stress by detecting resistance in this embodiment, detect and measure the mechanical stresses in each measuring prong 6.1, 6.2, 7 resulting from the skier's acting on each ski.
The force which enters the base plate 50 through the central stiff portion 3 is transferred through the first support fastening elements 9.1, 9.2 and the second support fastening element 10 to the ski 2, thus creating a relatively huge mechanical stress in each measuring prong 6.1, 6.2, 7. The difference between the sum of the measured values of the mechanical stress of the sensors 11 arranged in the first measuring prongs 6.1 and 6.2 and the measured values of the mechanical stress of the sensor 11 arranged in the second measuring prong 7 serves as a basis for obtaining data on the position of the skier's balance point with respect to each ski, forward-backward tilt. The data on the skier's tilt and the magnitude of the force exerted on the edge of each ski is obtained on the basis of the difference between the measured values of the mechanical stress of the sensors 11 arranged in the first measuring prongs 6.1 and 6.2.
A second embodiment of the base plate of the invention is a base plate 60 with a first fastening portion 4 conceived identically as in the base plate of the first embodiment and a second fastening portion 5 comprising two measuring prongs 7.1, 7.2 mutually spaced apart by a separating groove 8. Each measuring prong 7.1, 7.2 is provided with a centrally formed hole 23.1, 23.2 for the reception of a support fastening element 10.1, 10.2 for fastening the second fastening portion 5 or the base plate 60 to the ski 2. Each hole 23.1, 23.2 and each support fastening element 10.1, 10.2, which is executed as a screw with a spacer in this embodiment, form a fixed support to the base plate 60. On the upper surface of the first 4 and second fastening portions 5 there is arranged a transversal groove 13 extending over the entire width of the first 4 and second fastening portions 5 and substantially neighbouring each end of the central stiff portion 3. The transversal groove 13 functions as a weakening spot with mechanical stresses of higher magnitudes. At the bottom side of each measuring prong 6.1, 6.2, 7.1, 7.2 in the area below the transversal groove 13, there is a seat 12, in which two sensors 11 for measuring mechanical stress are arranged. The sensors 11, which are the sensors for measuring mechanical stress by detecting resistance in this embodiment, detect and measure the mechanical stresses in each measuring prong 6.1, 6.2, 7.1, 7.2 resulting from the skier's acting on each ski.
Each sensor 11 for the measurement of the mechanical stresses transmits the measured values to a microcontroller 15 arranged in a seat 14 in the central stiff portion 3 of the base plate 50, 60 and inter alia including a processing unit, signal amplification electronic components, a battery with a power supply control. The digital signals from the sensors are transmitted via a communication module, which is preferably in the form of a wireless connection, such as Bluetooth, to a device that runs an application for evaluating the received signals. Such a device can be a smart phone that the skier keeps in his clothing. The evaluated signal values are forwarded to the skier in an acoustic, visual or other form by means of any known device for displaying signals as early as during a turn execution or/and are stored in a remote user interface for subsequent processing.
In order to obtain more detailed data on the load of each ski on various parts of the ski, a plurality of measuring spots are required. To this purpose, an assembly 20 of two base plates 50, 50'; 60, 60' of the invention can be used, said plates being longitudinally arranged on the ski at a mutual distance, such that one base plate 50, 60 supports the front ski binding and the second base plate 50', 60' supports the rear ski binding. Each base plate 50, 50'; 60, 60' is moulded at a space to a ski's upper surface distant from the base or embedded within the ski, said plate being shiftable in the longitudinal axis of the ski and prevented from shifting perpendicularly to the longitudinal axis of the ski.
Depending on the position of the skier's balance point, the action force gets distributed via the front ski binding to the front base plate 60, 50 and in via the rear ski binding to the rear base plate 60', 50' and creates relative mechanical stresses in each measuring prongs 6.1, 6.2, 7.1, 7.2 of each base plate 60, 60'; 50, 50'.
The assembly 20 of two base plates 50, 50'; 60, 60' of the invention allows for precise measurements of the loads in each ski in the area of the front ski binding and the rear ski binding, said loads resulting from the skier's force exerted on each ski depending on the position of his balance point. Precise data on the skier's forward-backward tilt and the magnitude of the force exerted on the edge of each ski can be obtained by measuring the mechanical stresses in the measuring prongs 6.1, 6.2, 7.1, 7.2 of each base plate 50, 50'; 60, 60'. The data on the position of the skier's forward-backward balance point can be obtained on the basis of the difference between the sum of the values of the mechanical stresses measured by each sensor 11 in the front base plate 60, 50 and the sum of the values of the mechanical stresses measured by each sensor 11 in the rear base plate 60', 50'. The data on the force, with which the skier acts on each edge of each ski can be obtained on the basis of the difference between the sum of the values of the mechanical stresses present on one side of the ski 2 in the base plate 60, 50 and the base plate 60', 50', measured by each sensor 11, and the sum of the values of the mechanical stresses present on the other side of the ski 2 in the base plate 60, 50 and the base plate 60', 50', measured by each sensor 11.
In the event of the assembly 20 of two base plates 60, 60'; 50, 50', the microcontroller 15, which is arranged in the central stiff portion 3 of each base plate 60, 60'; 50, 50' and inter alia including a processing unit, signal amplification electronic components, a battery with a power supply control, can be arranged in a housing portion 21. The housing portion 21 is arranged on the upper side of the ski in its central portion at a distance between the front 60, 50 and rear base plates 60', 50'. The microcontroller 15 receives the measured values of each sensors 11 and transmits them to a device that runs an application for the evaluation of the received signals.
As the base plate is arranged on each of both skis, the base plate 50, 60 of the invention or the assembly 20 of the base plates 60, 60'; 50, 50' of the invention make it possible to obtain very detailed data on the loads of both skis in a certain moment of skiing.
Understandably, the assembly 20 of the base plates 60, 60'; 50, 50' can comprise two base plates which differ in the number of measuring spots and are arranged in series or inversely with respect to each other.

Claims

A base plate (50, 60) moulded at a space to a ski's (2) upper surface distant from the base in its central portion or embedded within the ski (2), said plate being shiftable in the longitudinal axis of the ski, prevented from shifting perpendicularly to the longitudinal axis of the ski and configured to receive a front and/or rear ski binding, wherein the base plate comprises
a central stiff portion (3) with fastening holes for fastening a front and/or rear ski binding,
a first fastening portion (4) moulded to one end of the central stiff portion (3),
a second fastening portion (5) moulded to another end of the central stiff portion (3), characterized in that
the first fastening portion (4) is configured as a measuring portion comprising
a transversal groove (13) arranged on the upper ski-distant surface and extending along the central stiff portion (3),
two measuring prongs (6.1, 6.2) spaced apart by a separating groove (8),
two sensors (11) for the measurement of mechanical stress arranged on the ski proximal bottom surface of each measuring prong (6.1, 6.2) in the area of the transversal groove (13),
the second fastening portion (5) is configured as a measuring portion comprising a transversal groove (13) arranged on the upper ski-distant surface and extending along the central stiff portion (3),
at least one measuring prong (7),
at least one sensor (11) for the measurement of mechanical stress arranged on the ski proximal bottom surface of the measuring prong (7) in the area of the transversal groove (13),
wherein each transversal groove (13) functions as a weakening spot of mechanical stresses.
Base plate according to claim 1, characterized in that the second fastening portion (5) comprises two measuring prongs (7.1, 7.2) distanced by a separating groove (8), and two sensors (11) for the measurement of mechanical stress arranged on the ski proximal bottom surface of each measuring prong (7.1, 7.2) in the area of the transversal groove (13).
Base plate according to any preceding claim, characterized in that the transversal groove (13) extends along the entire width of the front (4) and rear fastening portions (5).
Base plate according to any preceding claim, characterized in that the separating groove (8) extends longitudinally along the base plate (50) over the entire portion of the first (4) and second fastening portions (5).
Base plate according to any preceding claim, characterized in that the sensor (11) is arranged in a seat (12) located in the area below the transversal groove (13).
Base plate according to any preceding claim, characterized in that the central stiff portion (3) has a seat (14), in which a microcontroller (15) for measuring mechanical stress is arranged.
An assembly (20) of base plates (50, 60), characterized by comprising two base plates (50, 50', 60, 60') according to any of preceding claims.
Assembly (20) according to claim 7, characterized by comprising a housing portion (21), in which the microcontroller (15) is arranged.
Ski (2) comprising at least one base plate (50, 60) according to any of preceding claim 1 to 6.
Ski (2) comprising two base plates (50, 60) according to any of preceding claim 1 to 8.