WO2021255233A1

WO2021255233A1 - Motion device with body, platform and first and second foot

Info

Publication number: WO2021255233A1
Application number: PCT/EP2021/066574
Authority: WO
Inventors: Jens HELSTRUP
Original assignee: Helstrup Jens
Priority date: 2020-06-19
Filing date: 2021-06-18
Publication date: 2021-12-23

Abstract

Motion device (1), especially leisure sports device, for movement on ground in a direction of motion (M), comprising a body (2), a platform (3), an alignment mechanism, and two feet (5.1, 5.2). The platform (3) is able to rotate independently from the body (2) around a platform rotation axis (P) aligned essentially parallel to the direction of motion (M). The feet (5.1, 5.2) are each able to rotate independently from the body (2) around a respective foot rotation axis (F, S) aligned essentially parallel to the direction of motion (M). The alignment mechanism features transmission elements (7.1, 7.2) which couple the rotational motion or position of the feet (5.1, 5.1) around their respective foot rotation axis (F,S) with the rotational motion or position of the platform (3) around said platform rotation axis (P). The transmission elements (7.1, 7.2) transmit a coupling force from the feet (5.1, 5.2) to the platform (3) and vice versa by moving along transmission element paths arranged outside a plane perpendicular to the direction of motion (M).

Description

MOTION DEVICE WITH BODY, PLATFORM AND FIRST AND

SECOND FOOT

The invention relates to motion devices for movement on ground, in particular to leisure sports devices. And in particular to motion devices driven by gravity, for example for descending slopes. Such motion devices can for example be used for sports, leisure and fun in the area of gravity induced hill- or mountain descent for one, two or more people at a time.

Known motion devices of the kind as stated above, like skis or sleds, are for example used in mountain sports. The known motion devices generally require physical strength for example during their use (for example when steering them), during the preparation for their use and/or during their transport (from and to the location of their use and on the hill or mountain itself). The known motion devices also often involve a long and steep learning curve to master, and a high skill level is required to obtain carving sensations. Therefore, many people abstain from using them, or only get a limited experience due to the lack of skill and strength required to master their use.

For example, in alpine skiing, the motion device comprises of a pair of skis mounted on ski boots which are worn directly at the user's feet. Through this, the skis act as a direct extension of the user's feet and legs, and consequently have a big leverage effect and are highly sensitive to the overall balance and weight distribution induced by the user, which can go in all directions. In alpine skiing, there is therefore a significant strain on joints (particularly the knees), and due to the difficulty of maintaining balance and coordinating precise movements for two independently moving skis at the same time, skiing is difficult to learn and involves frequent falling and potential injuries. In order to obtain carving sensations in alpine skiing, a high skill level is required in order to maintain the skis in a rotated angle so that the side of the skis are engaging with the surface, while they are aligned essentially in parallel to the direction of motion, and where the user’s body weight is displaced towards the side of the turn in a fine balance in order to counter centrifugal forces, maintain balance and control the skis. This is a feat which requires excellent balance and technique, which is a skiing level that is difficult and lengthy to obtain, and is physically demanding. Furthermore, sports equipment (in the case of alpine skiing: at least two skis, two ski poles and two ski boots) is often bulky and difficult to transport and to store, adding to the nuisance. This leaves many people desisting from progressing, or even going to the hills or mountains in the first place.

Known motion devices alternative to skis are for example sleds or ski or runner supported devices as for example described in patent applications US4219207A, US5573257A, US6241265B1 or FR2813021A1. Such devices can typically be used with a learning curve less steep compared to skiing because the skis or runners are fixed to a structure and do not have to be controlled individually. Also, the user is typically sitting on the device, which reduces the effort of keeping the balance and coordinating motion at the same time. Ski poles also do not interfere and therefore do not complicate the use of such devices. However, devices like these are very limited in terms of movement and weight distribution and do not provide the carving sensation of alpine skiing due to these limitations, for example because the contact elements cannot be angled appropriately and/or because the user’s weight/center of gravity cannot be adequately and easily distributed to maintain the required balance and control to enable carving. For example, in the case of US4219207A, the seat (platform) remains parallel to the ground, thereby not displacing the weight/center of gravity of a user and not accounting for the centrifugal forces when turning, in a way required to carve. The centrifugal forces will in this case push the user’s body weight/center of gravity towards the outside of the device, which is the opposite direction of the direction of the sliding seat, making the use of this device both physically hard, unbalanced and counterintuitive. In the case of US5573257A, the sledge runners (contact bodies) remain flat on the ground, thereby not angling the contact bodies with the surface, which is a requirement for carving. This also increases the risk of the device flipping over when turning, as the outer edge of the contact bodies can get caught on the ground. Also, the footrest always remains in its initial flat position while the seat (platform) can tilt, leading to uncomfortable and ineffective twisting of the user’s body to induce steering. This again provides an ineffective displacement of weight/center of gravity of the user. Similarly, US6241265B1 is essentially a stiff structure which does not use carving but rather turning of the front contact elements around a vertically aligned axis to induce directional change (steering) instead of tilting the skis (contact bodies) required to carve. The lack of ability to incline and distribute the user’s weight/center of gravity also does not allow to obtain carving, for example because the centrifugal forces are not countered by the possibility of leaning into the turn. As for FR2813021A1, the user’s body is essentially locked into a fixed position and no handles are available, making it particularly challenging to displace the weight/center of gravity for the user, as the entire device needs to be tilted without any fixed point for the user to push or pull from. This is physically demanding as the device construct is large and heavy and only allows the user to move the arms and upper body to induce the weight displacement. Also, no brakes nor other means of steering are provided, giving this device a steep learning curve, and has limited steering and braking, making the device less safe, particularly when learning. The sheer size, weight and lack of foldability of this device is also particularly obstructive for easy transport and use. This is also the case with the other devices, which are all bulky and difficult to transport. Furthermore, these ski or runner supported devices are generally much bigger and heavier than ski equipment, making transport and storage difficult and a nuisance.

In order to obtain a true carving sensation in hill- or mountain descent, adequate displacement of weight/the center of gravity of the user is essential, as is the angling of the contact bodies for snow carving and disadvantages of the known motion devices

(including alpine skiing), such as a steep learning curve, limited mechanical flexibility, e.g., to angle contact bodies and/or displace weight/center of gravity, intense physical effort (during use and/or transport), safety issues such as limited of steering and braking ability (during use and/or transport) and/or low transportability and/or storage practicability need to be solved or reduced in order to overcome a lot of the barriers hindering people from enjoying this type of activity.

This invention aims to remove at least partially at least one of the disadvantages described above. In other words, this invention for example solves at least partially at least one of the issues of the above-mentioned devices regarding limitation of movement, limitation of weight distribution, reduced ease of use, lack of steering and braking ability, problematic transportability/storage, lack of an alpine carving sensation and/or steep learning curve.

The inventive motion device, especially leisure sports device, for movement on ground in a direction of motion, comprises a body, a platform, an alignment mechanism, a first foot and a second foot. The body is mechanically connected to the platform, and the platform is able to rotate independently from the body around a platform rotation axis aligned essentially parallel to the direction of motion. Furthermore, the body is mechanically connected to the first foot, and the first foot is able to rotate independently from the body around a first foot rotation axis aligned essentially parallel to the direction of motion. Furthermore, the body is mechanically connected to the second foot, and the second foot is able to rotate independently from the body around a second foot rotation axis aligned essentially parallel to the direction of motion. The first foot is designed for a coupling in a rigid manner to a first contact body for being by way of the first contact body in mechanical contact with the ground during the movement of the motion device on the ground. And the second foot is designed for a coupling in a rigid manner to a second contact body, for being by way of the second contact body in mechanical contact with the ground during the movement of the motion device on the ground. The alignment mechanism features a first transmission element which couples the rotational motion or position of the first foot around said first foot rotation axis with the rotational motion or position of the platform around said platform rotation axis, and the alignment mechanism features a second transmission element which couples the rotational motion or position of the second foot around said second foot rotation axis with the rotational motion or position of the platform around said platform rotation axis. The first transmission element transmits a coupling force from the first foot to the platform and vice versa by moving along a first transmission element path arranged outside a plane perpendicular to the direction of motion. And the second transmission element transmits a coupling force from the second foot to the platform and vice versa by moving along a second transmission element path arranged outside a plane perpendicular to the direction of motion.

The description of the inventive motion device above and the according explanations below refer to a motion device in a configuration ready for use. This means the described motion device is a drive configuration. The motion device is constructed for movement on the ground in the movement direction, i.e. in direction of motion. In its drive configuration, the first foot and the second foot of the motion device are coupled to the first contact body and the second contact body respectively. The coupling of the contact body to the foot can be a releasable coupling.

The first contact body and the second contact body are not comprised by the inventive motion device. The first contact body and the second contact body can vary in design and/or function, can be exchanged and can be provided by different producers. A contact body can for example comprise or be a gliding element (like a ski), an elongated arrangement of rollers or wheels (like a rollerski) or an elongated chain- or belt-like device (like a grassski).

The body of the motion device is mechanically connected to the platform, and the platform is able to rotate around a platform rotation axis which is aligned essentially parallel to the direction of motion, while the body is able to keep or change its rotational position with respect to said platform rotation axis independently from the rotational motion or position of the platform with respect to said platform rotation axis. The same applies in analog manner to the first foot and the second foot.

An axis being aligned essentially parallel to the direction of motion is an axis which features an inclination with respect to the direction of motion of 30 degrees or less. In particular, being aligned essentially parallel to the direction of motion means an axis which features an inclination with respect to the direction of motion of 15 degrees or less. Especially, this inclination with respect to the direction of motion is 5 degrees or less. The platform is in direct mechanical contact with a body of a user of this motion device and responds to mechanical interaction with this body of the user. The motion device can be steered by the user through interaction with the platform, which can easily be engaged by shifting the user's body weight. The motion device is spatially arranged between the user and the ground. By way of this, the motion device is separating the user from the ground.

The platform allows a good positioning of the user relative to the ground, facing in direction of motion. It also allows good control of the motion device due to good positioning of the user (good perception, good overview, comfortable position). The platform linked to the alignment mechanism ensures that weight shifts of the user's body are transmitted to the first and second foot intuitively, the same way that weight shifts induce directional and centrifugal changes when riding a bicycle or running. This allows for a highly intuitive interaction with the device and a flat learning curve. The majority of the user weight is also both concentrated over and transmitted through the platform, including when exposed to centrifugal forces, ensuring effective transmission of force, while allowing the user to focus on the ride itself.

The coupled rotation of the platform and the first foot and the second foot ensures intuitive induction of a force allowing a user to steer the motion device. It also allows to distribute weight adequately relative to the first foot and the second foot. And it allows to align a user body weight essentially parallel to a centrifugal axis in curves.

Besides a weight shift of the user, which induces a steering, i.e. a change of motion direction, a rotation of the first foot and the second foot around their respective axis (and in consequence an analogue rotation of the first and second contact bodies fixed to the first and second foot) also induces directional change (steering) as a direct extension of user weight displacement. The combination of the weight shift of the user and the rotation of the first and second foot amplifies the steering input and also increases surface grip for the first and the second contact body. This allows a short turn radius and increases an ability to resist centrifugal force away from the direction of movement (spin-out or skidding) and avoids risk of the device flipping over, compared to non-angled contact bodies or elements. This is a way to obtain a true carving feeling and is an intuitive way of steering and easy to learn, the learning curve for using such a motion device is therefore flat.

The platform controls both feet (i.e. the first foot and the second foot) and consequently both contact bodies (i.e. the first and the second contact body) once they are coupled to the feet for using the motion device. Compared to alpine skiing, the difficulty of use of the inventive motion device is low, as only the platform movement has to be controlled instead of a permanent control of independently moving skis (and ski poles). The inventive motion device is therefore easy to use and also reduces physical strain. It is also safe since the user can concentrate on the control of a single element (the platform) instead of for example two independent skis and two independent ski poles. The platform is optionally designed as a sitting platform. A sitting position reduces physical strain, particularly on joints, during the use of the motion device.

The platform is optionally designed free of coupling or attaching elements for the user. When the user is not firmly attached to the platform and the motion device in general, forces transmitted from the motion device to the user in case of heavy strain and/or an accident are limited. The use of this motion device is therefore safe. Compared to alpine skiing for example, where a ski fixed to a user's foot features a big leverage and consequently can break the foot or leg of the user, the inventive motion device is safer if the user is not firmly attached to the motion device.

The first foot is designed to be coupled, especially releasably coupled, in a rigid manner to a first contact body. The same applies to the second foot and a second contact body. The first foot and the second foot are indirectly connected to the ground during the movement of the motion device on the ground by way of the first contact body and the second contact body. The first foot can mechanically interact with the ground through the first contact body. The second foot can mechanically interact with the ground through the second contact body. The alignment mechanism comprises a first transmission element. This first transmission element couples the first foot and the platform with respect to their respective rotational motion around their respective rotation axis. In other words, the rotational position and movement of the first foot is linked to the rotational position and movement of the platform by way of the first transmission element. The same applies for the second transmission element with respect to the second foot and the platform.

The first transmission element for example is or comprises a wire, cable, a rope, a chain, a belt and/or fluid (especially hydraulic fluid). The same applies for the second transmission element.

The first transmission element and the second transmission element optionally are two distinct physical elements.

The first transmission element and the second transmission element optionally are parts of one single physical element. For example, one single wire connecting the first foot with the body and with the second foot can be interpreted as featuring a first transmission element which is coupling the first foot and the body (being the part of the wire between the body and the fist foot), and as featuring a second transmission element which is coupling the second foot and the body (being the part of the wire between the body and the second foot). The first transmission element transmits the coupling force from the first foot to the platform and vice versa by moving along a first transmission element path. This first transmission element path is arranged outside a plane perpendicular to the direction of motion. This means that the first transmission element path does not lie in its entire length perpendicular to the direction of motion. In other words, the first transmission element path at least partially exits a plane perpendicular to the direction of motion of the motion device. At least a part of the first transmission element path features a spatial configuration which is angled with respect to a plane perpendicular to the direction of motion. The same applies for the second transmission element path. In case of hydraulics or pneumatics i.e. when the transmission element is a fluid, force is transmitted by pressure but also by a small movement of the fluid. The first and/or second transmission element path is therefore also defined as the path along which the fluid is moving. For example, a tube filled with said transmission element fluid defines the transmission element path by a spatial arrangement of an inside of the tube. The arrangement of the transmission element path outside the plane perpendicular to the direction of motion allows a wide variation of different constructions of the motion device.

The arrangement of the transmission element path outside the plane perpendicular to the direction of motion ensures the transmission of an alignment force independently of the relative positioning of the feet and contact bodies relative to the platform. In other words, it allows the feet to move independently of the platform (but with their rotation coupled to the platforms rotation) without losing the coupling, i.e. a force transmission between the respective rotational movements. This allows to maintain the force transmission independently of the weight/center of gravity displacement and the relative position of the feet and the body, ensuring effective force transmission and that the geometry of the motion device is not affected by the force transmission. This way, the geometry of the motion device is independent from the force transmission, so that weight (resp. center of gravity) displacement and steering can be induced adequately, and optionally in different constructional configurations of the motion device (for example with single or dual suspension, independently moving legs or other constructional configurations), while the force transmission remains essentially unaffected and effective.

The arrangement of the transmission element path outside the plane perpendicular to the direction of motion allows to easily include gearing of the coupling between the platform and the feet respectively, or applying asymmetrical movement so that force and steering can be applied variably and with different ratios, further enhancing the ease of use, steering and efficiency. It can also be a weight saving mechanism since a wider choice of designs allows for a more lightweight construction with the same robustness in comparison with known designs like parallelograms. This design enables a flexible geometry which allows for movements and force transmission not otherwise possible with known mechanisms such as parallelograms. Therefore, the arrangement of the transmission element path outside the plane perpendicular to the direction of motion allows for example for good weight displacement, leading to the desired carving sensation, and/or it allows that different technical features or options can easily be included in the motion device.

In contrast to known devices with transmission element paths perpendicular to the direction of motion, like for example parallelograms, the arrangement outside the plane perpendicular to the direction of motion allows to easily include a folding or collapsible mechanism for folding or collapsing the motion device when not in use for easy storage and/or transport. It also allows to easily include a suspension mechanism for enhanced performance and/or enhanced comfort and ease of use of the motion device.

The combination of the coupling of the rotation of the platform and the first and the second foot with the transmission element path outside the plane perpendicular to the direction of motion allows for a lightweight, flexible geometry of the device where the feet and contact bodies can move independently from the body of the device while maintaining the force transmission and relative rotational position with the platform, which allows for adequate weight/gravity distribution and steering, thereby enabling intuitive carving. In other words, by removing variables that the user has to control and making the required movements an integrated part of the mechanical device, true carving sensations can be created with little effort. This is possible by having a single axis around which a user's body weight can easily be displaced in its entirety, i.e., a platform which can rotate in its full length, and by having independent feet/contact bodies which are distanced from the main body and are also rotating, users can simply and intuitively induce the adequate weight/centre of gravity displacement and steering to obtain true carving sensations without a steep learning curve. Therefore, the entire action of carving is reduced down to a simple motion of the user leaning to a side, thereby flattening the learning curve and limiting the physical effort and strain significantly.

The combination of the coupling and the transmission element path as described above replaces the need for secondary steering mechanisms and ensures an ergonomic, comfortable and safe use of the device with little effort. The force transmission outside a plane perpendicular to the direction of motion ensures the independent movement of the feet/contact bodies. For the motion device described above, the use of a direct parallelogram construct as in the state of the art is not possible or very complicated. The combination of the geometric design and the use of force transmission outside a plane perpendicular to the direction of motion solves or reduces at least partially at least one of the mentioned problems with other known motion devices. It also reduces the overall weight of the mechanism compared to other known devices.

Optionally the motion device comprises the first contact body and the second contact body. In particular, the first and second contact body feature a contact surface with the ground with a shape elongated in direction of motion.

A contact body can for example comprise or be a gliding element (like a ski), an elongated arrangement of rollers or wheels (like a rollerski) or an elongated chain- or belt-like device (like a grassski).

The coupling of the contact body to the respective foot can be non-releasable.

As an option, the first transmission element and the second transmission element are flexible elements transmitting force only in pulling direction, and especially are cables. The cables ensure efficient force transmission independently of the relative position of the device parts such as the platform/footrest, aligning element and feet. Such flexible elements are robust, cheap and reliable. Such a mechanical transmission allows for a light, weather resistant, cost-effective and reliable construction which is practically maintenance free and simple to repair if broken. Functional (spare) parts are commonly available in the market, ensuring no supply delays and overall low costs. Alternatively, the first transmission element and the second transmission element are flexible elements transmitting force both in pulling and pushing direction.

Optionally, the platform comprises a footrest for the driver. This footrest is fixed to the platform in a manner to ensure the same rotational alignment as the platform (with respect to the platform rotation axis). The footrest can be connected to the platform in a retractable and expandable manner.

The footrest allows a good and relaxing positioning of the user, saving the user energy and reducing physical strain (the user can drive longer than without footrest). In other words, the footrest provides ergonomically good body positions for the user and alleviates the effort of maintaining the feet off the ground, which is not normally the case with other seated hill descent devices.

The footrest provides high safety because the feet of the user are supported by the footrest, therefore minimizing a risk of entanglement of the feet of the user with the motion device and/or the ground. The rotation of the footrest in alignment with the platform allows for the user to intuitively tilt the full user body weight in the desired angle relative to the motion device, so that the weight displacement is effective and consistent across the full length of the motion device as well as the user body. Had the footrest not been rotating with the platform, the user would have had to uncomfortably twist his body, i.e. the user's torso relative to the feet, inducing both discomfort, as well as a less effective distribution of the overall weight. This leads to less grip and poorer steering as well as user fatigue and possible injury with extended use. In other words, the platform is connected to a footrest, which rotates in alignment with the platform, thereby ensuring that the full body of the user is equally displaced in its full length. This connection between the footrest and the platform also avoids twisting of the user’s body and ensures a comfortable riding position and that the feet are not in the way or risk getting injured.

The extendable/collapsible feature of the footrest allows for compact storage and transport of the device, and a compact overall design of the device, requiring a shorter motion device body length and less material/weight.

The connection of the footrest with the motion device is for example adjustable in distance. This allows for adapting the motion device for different user body sizes.

Alternatively, the platform can be built free of a footrest or free of an extendable/collapsible footrest mechanism.

Optionally, the motion device comprises a collapsing mechanism. The collapsing mechanism allows to reduce a size of the motion device by collapsing the motion device from a drive configuration into a smaller sized inert configuration.

The collapsing mechanism for example reduces the spatial extent of the motion device in the plane perpendicular to the direction of motion. In other words, by compacting the body orthogonal to the direction of motion, i.e. approaching the first foot and the second foot to the platform. The collapsing mechanism is especially a folding mechanism. Due to this collapsing mechanism, the motion device can be collapsed to the small sized inert configuration. This allows for a good transportability and storability of the motion device. By providing a collapsing or foldable design, the device can be easily carried, transported and stored. Transport is also safer when the motion device is compact due to less options to collide with the motion device. The inert configuration allows for easily transporting multiple motion devices on a journey to the place of use and enables users to bring the motion device with them on lifts and other transport devices otherwise not possible. The compact size in the inert configuration also reduces the space needed for long term storage and enables users to carry the device farther and higher than not collapsed devices, thereby extending the territory and options for using the motion device.

Alternatively, the device can be built free of a collapsing mechanism.

Optionally, the collapsing mechanism comprises a first leg for the first foot and a second leg for the second foot, the first leg and the second leg comprising the mechanical connection between the body and the first foot and the second foot respectively. In particular, the first leg and the second leg each comprise a parallelogram mechanism to ensure the same alignment of the first foot rotation axis and of the second foot rotation axis relative to the platform rotation axis in the drive configuration as well as in the inert configuration. The parallelogram mechanism of the legs can be nested, i.e., having one of the structural elements of the parallelogram placed within the other, so that the mechanism is shielded by the outer part, both of which comprise a structural element of the parallelogram. This uses less space and minimizes risk of injury and protects the mechanism from the elements, thereby reducing wear. Legs with parallelogram mechanisms are robust, cheap and reliable. The parallelogram mechanism ensures that the spatial position of the first and second foot rotation axis remains the same with respect to the platform rotation axis independently of the position of the legs. This allows easy combination of a suspension and/or the collapsing mechanism with the motion device, without impacting the steering abilities or other geometry relevant during use of the motion device.

Alternatively, the platform can be built free of legs or free of a parallelogram mechanism in legs.

Optionally, the legs comprise a housing enveloping the parallelogram mechanism. The housing of the leg shields an access to inner elements of the leg. In other words, the housing provides protection for parallelogram mechanism from external factors (for example snow, stones, mud). The motion device is therefore less prone to failure and/or damage due to external factors, especially during use. The housing protects the user's extremities from parallelogram mechanism, making the use of the motion device safe. The housing can for example feature a round or oval cross section.

The housing can feature an encapsulated and self-supporting design (nested parallelogram legs) which allows for containing the moving parts completely within the structure of the leg, therefore shielding the mechanics completely from external elements such as snow, dirt, stones and other mechanical risks as well as from user extremities, thereby minimizing wear and potential injuries.

Alternatively, the legs can be built free of a housing. Optionally, the motion device comprises a suspension for damping a force essentially perpendicular to the direction of motion. The suspension is arranged between the first foot and the platform and between the second foot and the platform.

In particular, the suspension is mechanically coupled to the collapsing mechanism. The suspension allows a good and comfortable experience for the user and increases safety through dampening of physical impact and by increasing stability, control and steerability of the device. It allows the user to save energy, resulting in a less exhausting experience. The user can consequently use the motion device longer than without suspension. The suspension provides high safety and good control of the motion device because feet respectively contact bodies can follow a contour of the ground. In other words, the suspension enables the user to have more control of the motion device, increases the overall safety and comfort and extends the period of use due to less physical impact on the user.

When the suspension is placed in the collapsing mechanism, it directly absorbs an impact from the contact bodies before it reaches the platform, maintaining the platform in the same state as before the impact.

In case that the suspension is coupled to the collapsing mechanism, the suspension can therefore make use of the same movement structures as the collapsing mechanism and damp the movement along the movement path of the collapsing mechanism. In other words, the damping results in a reversible and temporary collapsing movement of the collapsing mechanism (to an extend depending on the force to be damped). The suspension is not necessarily coupled to the collapsing mechanism, e.g., it could be part of the seating platform or the leg structure. Alternatively, the motion device can be built free of a suspension.

Optionally, the motion device comprises a brake operated manually by the driver. In particular, the brake is arranged at the first foot and/or at the second foot. For example, the brake does mechanically interact with the ground when operated.

The brake is for example operated by a pedal, lever and/or handle to be manipulated by the user with his hand and/or foot. In one embodiment of the brake, the mechanical interaction of the brake with the ground can be due to friction force and/or by deformation of the ground. Or the manual operation by the driver can activate a brake which works free of contact with the ground, such as a disc brake (for example when a contact body is different from a sliding element). The brake can therefore interact with a moving part of at least one contact body, for example a disc brake being connected to a roller on a roller ski or a belt of a grassski. The brake allows to directly control the speed of the motion device. The motion device features an increased safety due to an additional braking capability. The availability of a user operated brake enables to slow down the motion device independently from and in addition to braking actions obtainable from weight displacement. This allows the user to directly control the speed of the motion device by using the brake as well as to induce steering by using the brake, collectively increasing the safety and operability of the device, especially on regulated slopes.

Alternatively, the motion device can be built free of a brake. Optionally, the motion device comprises a handle fixed to the body. In particular, the handle comprises an actuator for operating the brake of the motion device.

The handle enhances the drivers control of the motion device. Handles that are fixed to the body and that are therefore independent from the feet and platform rotation position respectively and therefore allow the user to more easily displace the body weight by grabbing a fix-point (the handle) from which the body weight can be displaced relative to the platform by either a push or a pull of the handle. In other words, shifting the user's body weight can be facilitated by a simple push or pull against one of the handles. The handle i.e. the hand operated brake enables a highly intuitive operation of the brake mechanism which does not interfere with the body weight displacement of the user.

Optionally, the handles are self-opening/retracting in extent of the collapsing mechanism.

For example, the handles are folding out to their operational position in the drive configuration by means of a separate actuator driven by the collapsing mechanism during the transition from the inert to the drive configuration. In other words, the handles fold out automatically as part of an opening movement of the motion device.

This reduces effort and time required to open/close the motion device. By operating multiple device elements - like expanding the handle and expanding the collapsing mechanism - in a single operation minimizes the time required between the inert and the drive configuration, complexity and the number of actions the user has to take before using the device. This adds to the ease of use of the motion device. Alternatively, the motion device can be built free of a handle or free of a self opening/retracting mechanism.

Optionally, the motion device comprises a motorized drive.

The motorized drive makes the use of the motion device independent of a gravity and/or a slope, so that the device can be used on flat or inclined surfaces in all directions. This increases the use options beyond descent and other dependencies such as lifts. Specifically, the motorized drive can be engaged and disengaged, increasing the autonomous range of the motion device.

The motion device can be built free of a motorized drive. Optionally, the motion device comprises a gearing of the coupling between the platform and the feet.

A gearing allows that an angular speed of the rotational motion of the feet differs from an angular speed of the rotational motion of the platform. In other words, the coupling between the rotation of the feet and the rotation of the platform around their respective axes results in a proportional angular displacement (instead of the same angular displacement) when a gearing different from 1 is chosen.

For example, the gearing can be realized by using cables inducing rotational motion of round elements through tangentially applied forces, with the round elements featuring different diameters. The gearing allows to apply asymmetrical movement so that force and steering can be applied variably and with different ratios, further enhancing the ease of use, steering and efficiency of the motion device.

Alternatively, the motion device can be built free of a gearing of the coupling between the platform and the feet.

The subject matter of the invention will be explained in more detail in the following text with reference to an exemplary embodiment which is schematically illustrated in the attached drawings, in which:

Figure 1 shows a perspective view of a motion device in drive configuration, Figure 2 shows a side view of the motion device in drive configuration, Figure 3 shows a side view of the motion device in inert configuration, Figure 4 shows a rear view of the motion device in drive configuration, Figure 5 shows a rear view of the motion device in inert configuration, Figure 6 shows a rear view of the motion device in drive configuration in a tilted state.

All figures 1 to 6 show the same embodiment of the inventive motion device. For better understanding, not all reference numbers are shown in all figures due to space limitations.

Figure 1 shows a perspective view of the motion device (1) in drive configuration. A platform (3) is rotatably connected to a body (2) which comprises a first leg (12.1) and a second leg (12.2). The first leg (12.1) ends in a first foot (5.1), and the second led (12.2) ends in a second foot (5.2). Coupled to these feet (5.1, 5.2) are contact bodies (6.1, 6.2) in form of skis. A direction of motion (M) is shown as a solid arrow.

The platform (3) comprises a seat and is connected to a retractable footrest (10). The footrest (10) is fixed to the platform (3) in such a way that the footrest (10) tilt together with the platform (3) around a platform rotation axis (P). The body (2) does not tilt together with the platform (3) and the footrest (10) around the platform rotation axis (P). The platform rotation axis (P) is parallel to the direction of motion (M).

The first foot (5.1) is able to rotate around the first foot rotation axis (F), which is parallel to the direction of motion (M). And the second foot (5.2) is able to rotate around the second foot rotation axis (S), which is parallel to the direction of motion (M). The rotation of the feet (5.1, 5.2) around their axes (F, S) is coupled to the rotation of the platform (3) around its axis (P) via an alignment mechanism which is best understood by looking at its easiest recognizable components: the first transmission element (7.1) and the second transmission element (7.2). Both transmission elements (7.1, 7.2) feature two cables each (a cable for each direction of transmission movement). Both transmission elements (7.1, 7.2) ensure that a rotation of the platform (3) induces a rotation of the feet (5.1, 5.2) and vice versa.

The feet (5.1, 5.2) feature brakes (14.1, 14.2) which work like known ski brakes: if activated, the brakes (14.1, 14.2) interact with the ground by creating friction and thus a braking force. The brakes (14.1, 14.2) are activated by brake levers (16.1, 16.2) which are mounted on handles (15.1, 15.2). The handles (15.1, 15.2) are fixed to the legs (12.1, 12.2) and thus to the body (2) and therefore are independent from the rotation of the platform (3). The body (2) features a collapsing mechanism (11) which allows to fold the legs (12.1 , 12.2) towards the platform (3), reducing a size of the whole motion device (1) for easy transport and stowage. The collapsing mechanism (11) is used by a suspension (13) which damps motions by allowing the motion device (1) to temporarily collapse to a limited extent.

Figures 2 and 3 show a side view of the motion device (1). In figure 2, the drive configuration is shown where collapsing mechanism (11) is extended. In figure 3, the collapsing mechanism (11) is collapsed, and the motion device (1) is in its inert configuration. In both configurations and in between, the feet (5.1, 5.2) and therefore also the contact bodies (6.1, 6.2) stay parallel to the platform (3). In other words, the feet rotation axes (F, S) are always kept parallel to the platform rotation axis (P) in his embodiment of the motion device (1).

Figures 4 and 5 show a rear view of the motion device (1): in drive configuration in figure 4, and in inert configuration in figure 5. In figure 4, the brakes (14.1, 14.2) are shown in activated position (braking), whereas in figure 5, the brakes (14.1, 14.2) are shown in an inactivated position (not braking, like in figures 1 to 4).

Figure 6 shows the same rear view of the motion device (1) in drive configuration as in figure 4, but in a tilted state. This means that the platform (3), the footrest (10) and the feet (5.1, 5.2) with the contact bodies (6.1, 6.2) are tilted, i.e. rotated around their respective axes (P, F, S), while the body (2) including its legs (12.1, 12.2) and the handles (15.1, 15.2) are not tilted relative to the ground.

Claims

PATENT CLAIMS:

1. Motion device (1), especially leisure sports device, for movement on ground in a direction of motion (M), comprising a body (2), a platform (3), an alignment mechanism, a first foot (5.1) and a second foot (5.2), wherein the body (2) is mechanically connected to the platform (3), and the platform (3) is able to rotate independently from the body (2) around a platform rotation axis (P) aligned essentially parallel to the direction of motion (M), wherein the body (2) is mechanically connected to the first foot (5.1), and the first foot (5.1) is able to rotate independently from the body (2) around a first foot rotation axis (F) aligned essentially parallel to the direction of motion (M), wherein the body (2) is mechanically connected to the second foot (5.2), and the second foot (5.2) is able to rotate independently from the body (2) around a second foot rotation axis (S) aligned essentially parallel to the direction of motion (M), wherein the first foot (5.1) is designed for a coupling in a rigid manner to a first contact body (6.1), for being by way of the first contact body (6.1) in mechanical contact with the ground during the movement of the motion device (1) on the ground, - wherein the second foot (5.2) is designed for a coupling in a rigid manner to a second contact body (6.2), for being by way of the second contact body (6.2) in mechanical contact with the ground during the movement of the motion device (1) on the ground, wherein the alignment mechanism features a first transmission element (7.1) which couples the rotational motion or position of the first foot (5.1) around said first foot rotation axis (F) with the rotational motion or position of the platform (3) around said platform rotation axis (P), and the alignment mechanism features a second transmission element (7.2) which couples the rotational motion or position of the second foot (5.2) around said second foot rotation axis (S) with the rotational motion or position of the platform (3) around said platform rotation axis (P), wherein the first transmission element (7.1) transmits a coupling force from the first foot (5.1) to the platform (3) and vice versa by moving along a first transmission element path arranged outside a plane perpendicular to the direction of motion (M), and the second transmission element (7.2) transmits a coupling force from the second foot (5.2) to the platform (3) and vice versa by moving along a second transmission element path arranged outside a plane perpendicular to the direction of motion (M).

2. Motion device (1) according to claim 1, wherein the first transmission element (7.1) and the second transmission element (7.2) are flexible elements transmitting force only in pulling direction, and especially are cables. 3. Motion device (1) according to claim 1 or 2, wherein the platform (3) comprises a footrest (10) for the driver, the footrest (10) fixed to the platform (3) in a manner to ensure the same rotational alignment as the platform (3), the footrest

(10) especially being connected to the platform (3) in a retractable and expandable manner.

4. Motion device (1) according to one of the preceding claims, wherein the motion device (1) comprises a collapsing mechanism (11), the collapsing mechanism

(11) allowing to reduce a size of the motion device (1) by collapsing the motion device (1) from a drive configuration into a smaller sized inert configuration.

5. Motion device (1) according to claim 4, wherein the collapsing mechanism (11) comprises a first leg (12.1) for the first foot (5.1) and a second leg (12.2) for the second foot (5.2), the first leg (12.1) and the second leg (12.2) comprising the mechanical connection between the body (2) and the first foot (5.1) and the second foot (5.2) respectively, and in particular the first leg (12.1) and the second leg (12.2) each comprise a parallelogram mechanism to ensure the same alignment of the first foot rotation axis (F) and of the second foot rotation axis (S) relative to the platform rotation axis (P) in the drive configuration as well as in the inert configuration.

6. Motion device (1) according to claim 5, wherein the legs (12.1,12.2) comprise a housing enveloping the parallelogram mechanism. 7. Motion device ( 1 ) according to one of the preceding claims, wherein the motion device (1) comprises a brake (14.1,14.2) operated manually by the driver, the brake (14.1,14.2) being arranged at the first foot (5.1) and/or at the second foot (5.2), in particular to mechanically interact with the ground or with a moving part of at least one contact body (6.1,6.2) when operated.

8. Motion device (1) according to one of the preceding claims, wherein the motion device (1) comprises a suspension (13) for damping a force essentially perpendicular to the direction of motion (M), arranged between the first foot (5.1) and the platform (3) and between the second foot (5.2) and the platform (3), the suspension (13) in particular being mechanically coupled to the collapsing mechanism (11).

9. Motion device (1) according to one of the preceding claims, wherein the motion device (1) comprises a handle (15.1,15.2) fixed to the body (2), the handle (15.1,15.2) in particular comprising an actuator (16.1,16.2) for operating the brake (14.1,14.2) of the motion device (1).

10. Motion device (1 ) according to one of the preceding claims, wherein the motion device (1) comprises a gearing of the coupling between the platform (3) and the first and second foot (5.1,5.2).