WO2017068393A1

WO2017068393A1 - Bicycle simulator with adjustable geometry

Info

Publication number: WO2017068393A1
Application number: PCT/IB2015/058108
Authority: WO
Inventors: Giovanni MORTARA
Original assignee: Prodit Engineering S.P.A.
Priority date: 2015-10-21
Filing date: 2015-10-21
Publication date: 2017-04-27

Abstract

The simulator comprises an adjustable-geometry stationary bicycle (1) and a control system (110) for adjusting the geometry of the stationary bicycle (1). The stationary bicycle (1) comprises a frame (2), a saddle (14), a handlebar (12) and a pair of pedals (16). The frame (2) comprises a plurality of frame elements (22, 26, 30, 34, 38, 42, 46, 50) connected to each other by hinges (71, 72, 73, 74, 75, 76). The control system (110) comprises at least one linear actuator (24, 28, 32, 36, 40, 44, 48, 52) arranged to change the length of a respective frame element (22, 26, 30, 34, 38, 42, 46, 50) along a given direction and a processing unit (90) configured to control said at least one linear actuator (24, 28, 32, 36, 40, 44, 48, 52) to obtain the desired geometric configuration of the stationary bicycle.

Description

Bicycle simulator with adjustable geometry

Technical field The present invention relates in general to the bicycle field; in particular, the invention relates to a bicycle simulator that enables the geometry and dimensions of the components of the simulated bicycle to be adjusted in an automatic or automated manner in order to adapt them to the anthropometric characteristics and posture of a given cyclist when pedalling. Prior art

When buying a new bicycle, choosing the geometry of the frame and of the other components of the bicycle (for example handlebar, saddle and crank arms) is a fundamental aspect, since a wrongly sized bicycle can give rise to numerous problems. Furthermore, in order to optimize the amount of power that the cyclist can transfer to the bicycle, it is important that the geometry of the frame enables a good balance between comfort and performance.

Nowadays, the bicycle is adjusted manually to match the specific anthropometric charac- teristics of the cyclist, measuring the dimensions of the body segments (torso, arms, legs) and transferring said information to a specific frame size using the experience of persons skilled in the art. Further adjustments are then made to the frame while the cyclist is pedalling on the bicycle, which is appropriately seated on rollers or suspended at the rear wheel. The adjustments are mainly made to the saddle (front-rear inclination and longitudinal po- sition) and to the handlebar (height from ground, distance from saddle, inclination).

Disadvantageous^, due to practical difficulties, most adjustments can only be made when the cyclist is not on the bicycle or is not pedalling. Understandably, this limitation on the one hand requires the cyclist to stop pedalling and to get off the bicycle several times, and on the other adversely affects the quality of the adjustment.

There are several solutions in the prior art that address the problem in two different ways. US2007/0142177A1 proposes an apparatus for quantitatively assessing the ergonomic fit between a person and a bicycle by means of locating systems using markers. However, this document does not describe in detail a system that is able to adjust the dimensions of the frame during pedalling, but describes a system for locating and collecting statistical data of the markers positioned on body segments of the cyclist in order to assess and optimize a particular physiological target during pedalling.

In US7905817B2, on the other hand, a stationary bicycle is provided with actuators positioned between the frame and the saddle, between the frame and the handlebar and beneath the saddle in order to adjust the positions of the handlebar and of the saddle in two directions perpendicular to one another in an automated manner using a control system. However, this solution does not enable the inclination of the saddle, of the handlebar or of the elements that make up the frame to be adjusted in an automated manner. As a result, none of the above-mentioned documents is able to solve the problem of adjusting the positions and angles of the component parts of the bicycle in an automated and controlled manner.

Summary of the invention

It is an object of the present invention to provide a bicycle simulator that enables the geometry of the simulated bicycle to be adjusted in an automated manner, even during pedalling, in order to identify the sizes and geometry of the frame and of other components of the bicycle that are most suited to a particular cyclist.

This and other objects and advantages are achieved, according to an aspect of the invention, by a bicycle simulator comprising a stationary bicycle and a control system that is able to adjust the geometry of the stationary bicycle, wherein the stationary bicycle includes a frame, a saddle, a handlebar and a pair of pedals, wherein said frame includes a plurality of frame elements joined together by means of hinges and wherein the control system includes at least one linear actuator arranged to vary the length of a respective frame element in a given direction and a processing unit configured to control said linear actuator to. implement the desired geometric configuration of the stationary bicycle, as specified in independent claim 1.

By virtue of such a configuration, the bicycle simulator allows to vary continuously the geometry and the position of the components of the bicycle (for example frame, handlebar, saddle, etc.) during pedalling, without requiring the cyclist to get off the simulator or interrupt the activity.

The control system is able to receive position information for each linear actuator and therefore impart commands to adjust the position in the 2D space of the hinges, by having the linear actuators shorten or lengthen the elements. In this way, adjusting the position of the hinges and the lengths of the elements varies the overall geometry of the component parts of the bicycle, ensuring a better fit of the frame, saddle, handlebar and pedals to the physical characteristics and the posture of the cyclist.

Preferred embodiments of the invention are specified in the dependent claims.

In an embodiment of the invention, the bicycle simulator includes at least one frame element comprising two segments that are movable reciprocally in a given direction, wherein at least one linear actuator is positioned in series with or in parallel to the two segments.

Preferably, the control system further comprises adjusting means for adjusting the vertical position and the longitudinal position of the saddle or of the handlebar, wherein said adjusting means comprise a first and a second linear actuator controllable by the processing unit to adjust the vertical position and the longitudinal position of the saddle or of the handlebar, respectively.

In another embodiment of the invention, the control system further includes adjusting means for adjusting the inclination of the saddle or of the handlebar.

Preferably, the control system is also configured to vary the position of the hinges sequentially, moving one hinge at a time, whereby moving a hinge lengthens and rotates the frame elements connected thereto, but does not move any other hinges.

In an embodiment of the invention the axes of the hinges are incident on the vertical plane of the stationary bicycle.

Preferably, the hinges are idle hinges and if possible the axes of same are substantially perpendicular to a sagittal vertical plane of the stationary bicycle and are movable in said plane. Preferably, the stationary bicycle further includes a bottom bracket shell in which two crank arms connected rotatingly to the pedals are hinged, in such a manner that said crank arms are connected to a brake able to adjust the torque required to move said crank arms, to enable pedalling to be assessed also when the cyclist is applying variable forces. Moreover, the control system preferably also comprises length adjusting means for adjusting the length of the crank arms, with the advantage of enabling adjustment of the lever arm that determines the torque exerted on the hinge about which the crank arms rotate.

According to a first embodiment, the control system is arranged to automatically actuate the linear actuators using the position data of the actuators and the anthropometric and postural characteristics of a given cyclist during pedalling.

According to a second embodiment, the control system is arranged to control the linear actuators in response to a command by which the user identifies the hinge to be moved in a given direction and/or the frame element to be adjusted in length.

Moreover, the control system is preferably arranged to adjust the position of the hinges sequentially, moving one hinge at a time, in such a manner that moving a hinge lengthens and rotates the elements connected thereto, without moving any other hinges, thereby mak- ing it possible to simplify the control and to monitor one parameter at a time to determine the posture of the cyclist on the bicycle. According to another embodiment, each hinge moves in two predefined absolute directions (for example vertical and horizontal direction in relation to the plane on which the bicycle rests) or along the axes of the elements to which the hinge is connected. According to an embodiment, the control system is also able to calculate the size of the frame most suited to the specific cyclist, using information collected from sensors.

Brief description of the drawings The functional and structural characteristics of some preferred embodiments of an adjustable-geometry bicycle simulator according to the invention will be described below. Reference is made to the attached drawings, in which:

Figure 1 shows schematically a bicycle simulator according to an embodiment of the invention, and

Figure 2 is a block diagram of an example of a control system for a bicycle simulator according to the invention.

Detailed description Before describing the embodiments of the invention in detail, it should be noted that application of the invention is not limited to the structural details and to the configuration of the components set out in the following description or illustrated in the drawings. Other embodiments of the invention are conceivable and the invention may be implemented or put into practice in different ways. Furthermore, the phrases and terms used herein are for de- scriptive purposes and should not be understood to be limiting.

With reference first to Figure 1 , a bicycle simulator according to a preferred embodiment of the present invention includes a stationary bicycle, generally indicated 1, which comprises a plurality of elements connected to each other by a plurality of hinges positioned on at least one of the portions of said elements, so as to simulate the components (which are already known) of a bicycle, namely a frame 2, a fork 10, a handlebar 12, a saddle 14, a seat post 15 and a pair of pedals 16. Said elements may be provided with a plurality of lin- ear actuators operable to vary the length of the element, and consequently the distance between the hinges. Furthermore, these elements may include at least two segments, whereby at least one linear actuator is connected- to the two segments to control the reciprocal movement thereof in a given direction.

In the embodiment shown in Figure 1 , the linear actuators are positioned in series with the two segments forming the elements that make up the components of the bicycle, in such a manner that two portions of the segments (for example the end portions of the segments) are connected to the linear actuator and other two portions are connected to the hinges.

On the other hand, in another embodiment (not shown) the linear actuators are positioned in parallel with the two segments forming the elements, for example so that one of the two segments can partially penetrate the other segment to form a telescopic element moved by the actuator.

In an embodiment of the invention, the frame 2 includes a plurality of elements connected to each other by a plurality of hinges. For example, an element 22 simulating the corresponding seat tube of a bicycle is connected by a hinge 71 to another element 26 simulating the corresponding top tube of a bicycle and to another element 50 simulating the corre- sponding seat stay of a bicycle. A portion, opposite to the hinge 71, of the element 22 simulating the corresponding seat tube of a bicycle is connected by another hinge 74 to an element 46 simulating the corresponding chain stay of a bicycle, to another element 34 simulating the corresponding oblique tube of a bicycle and to another auxiliary element 42, this latter not usually being present on a bicycle. A portion, opposite to the hinge 74, of the element 46 simulating the corresponding chain stay of a bicycle is connected by a hinge 75 to the element 50 simulating the corresponding seat stay of a bicycle. Preferably, said hinge 75 is connected to a support 81 that enables the hinge to move only in a given direction, preferably parallel to the plane on which the bicycle rests. The element 34 simulating the corresponding oblique tube of a bicycle, at the end opposite to the hinge 74, is preferably connected by a hinge 73 to an element 38 simulating the corresponding fork 10 of a bicycle and to another element 30 simulating the corresponding head tube of a bicycle.

The element 38 simulating the corresponding fork 10 of a bicycle is connected, at the end opposite to the hinge 73, to the auxiliary element 42 by a hinge 76, which is connected to a support 80 that enables the hinge to move only in a given direction, preferably parallel to the plane on which the bicycle rests.

The opposite end of the element 30 simulating the corresponding head tube of a bicycle is connected by a hinge 72 to the element 26 simulating the corresponding top tube of a bicy- cle.

At least one of the elements 22, 26, 30, 34, 38, 42, 46, 50 forming the corresponding frame 2 of a bicycle is split into two segments, respectively indicated with 22a and 22b, 26a and 26b, 30a and 30b, 34a and 34b, 38a and 38b, 42a and 42b, 46a and 46b, 50a and 50b.

At least one of the elements 22, 26, 30, 34, 38, 42, 46, 50 forming the corresponding frame 2 of a bicycle can be adjusted in length using linear actuators indicated respectively with 24, 28, 32, 36, 40, 44, 48, 52. Preferably, as in the embodiment shown in Figure 1, all the elements 22, 26, 30, 34, 38, 42, 46, 50 forming the corresponding frame 2 of a bicycle are split into two segments and are provided with respective linear actuators in order to provide the widest possible adjustment range. Preferably, said linear actuators are connected to the hinge-free portions of the segments 22a and 22b, 26a and 26b, 30a and 30b, 34a and 34b, 38a and 38b, 42a and 42b, 46a and 46b, 50a and 50b forming the elements of the frame.

Preferably, all the aforementioned hinges, which along with the aforementioned elements simulate the frame 2 of a bicycle, are idle hinges.

In a preferred embodiment, the hinges 75 and 76, which connect the frame 2 to the sup- ports 80 and 81 used to bear the load of same, are adjustable in directions parallel to the plane on which the bicycle rests, preferably separately using predetermined positions along a front-to-rear direction of movement, as indicated by arrows F. The specific configuration of the hinges and of the elements extendable by means of linear actuators make it possible to freely and finely change the geometry of the frame, even while the cyclist is pedalling.

For example, the linear actuator 48 enables the distance between the rear wheel 51 and the bottom bracket shell 82 to be adjusted, or the linear actuator 40 enables the length and inclination of the fork 10 to be adjusted, and the linear actuator 24 enables the inclination and height-from-ground of the saddle to be adjusted by lengthening or shortening the element 22 simulating the corresponding seat tube of a bicycle. In an embodiment of the invention, the corresponding components of a bicycle that are not usually considered to be part of the frame are also simulated: the handlebar 12, the saddle 14, the seat post 15, a saddle frame 58 and the pedals 16. The position and orientation of such components can also be varied using elements of adjustable length and/or hinges, as shown in Figure 1.

For example, the corresponding handlebar 12 of a bicycle is simulated in Figure 1 by a bar 13, an upper stem element 64 and a lower stem element 60.

Preferably, the lower stem element 60 is connected by a hinge 72 to the element 26 simu- lating the corresponding top tube and to the element 30 simulating the head tube. The upper stem element 64 is connected by a hinge 77 to the end of the lower stem element 60 opposite to the hinge 72. The bar 13 is connected by a hinge 78 to the upper stem element 64 at the end opposite to the hinge 77. Preferably, the stem elements 60 and 64 are each split into two segments, respectively indicated with 60a, 60b and 64a, 64b. Preferably, the length of the stem elements 60 and 64 can be adjusted by means of a respective linear actuator 62 and 66.

Preferably, said linear actuators 62 and 66 are connected to the hinge-free portions of the segments 60a and 60b, 64a and 64b forming the elements of the handlebar 12.

The vertical position of the handlebar cam thus be adjusted by means of the linear actuator 62, while the longitudinal position can be adjusted by means of the linear actuator 66. The two hinges 77 and 78 linking, the first one, the two stem elements 60 and 64 to each other and, the second one, the bar 13 to the upper stem element 64 can be manually locked in defined angular positions or be controlled by means of respective rotary actuators (not shown). In an embodiment of the invention, the element 54 simulating the corresponding seat post 15 of a bicycle is connected by the hinge 71 to the element 26 simulating the corresponding top tube, to the element 22 simulating the corresponding seat tube of a bicycle and to the element 50 simulating the seat stay. Preferably, at the end opposite to the hinge 71 the element 54 simulating the corresponding seat post 15 of a bicycle is connected to the cor- responding saddle frame 58 by a hinge 79.

Preferably, the element 54 simulating the corresponding seat post 15 of a bicycle is split into two segments 54a and 54b. Preferably, the length of the element 54 simulating the corresponding seat post 15 of a bicycle can be adjusted by means of a linear actuator 56.

Preferably, said linear actuator 56 is connected to the hinge-free portions of the segments 54a and 54b forming the element 54 simulating the corresponding seat post 15.

In an embodiment of the invention, the element 58 simulating the corresponding frame of the saddle of a bicycle is split into two segments 58a and 58b. Preferably, the length of the element 58 simulating the corresponding saddle frame of a bicycle can be adjusted by means of a linear actuator 59.

Preferably, said linear actuator 59 is connected to the hinge-free portions of the segments 58a and 58b forming the element 58 simulating the corresponding saddle frame of a bicycle.

This configuration makes it possible to adjust the vertical position and the longitudinal position of the saddle 14 using the linear actuator 56 and the linear actuator 59, respectively, while the inclination of the saddle 14 can be adjusted using the hinge 79, which can be locked manually in defined angular positions or be controlled by means of a rotary actuator (not shown).

Preferably, the element 22 simulating the corresponding seat tube of a bicycle and the ele- ment 54 simulating the corresponding seat post 15 of a bicycle need also to be connected to each other by means enabling the two aforementioned elements to be locked at a given angle to each other.

In an embodiment of the invention, the stationary bicycle includes a bottom bracket shell 82 that contains the hinge 74 shared by the elements simulating the corresponding chain stays 46, seat tube 22, oblique tube 34 and auxiliary element 42.

Preferably, the crank arms 68 are hinged to the bottom bracket shell 82 such that a transmission system connects said crank arms to a brake 86 (for example a mechanical, elec- tromechanical or magnetic brake) that is able to adjust the torque required to move the crank arms 68.

According to an embodiment, the bottom bracket shell 82 can be moved in a given direction by means of a linear actuator 84.

According to another embodiment, the length of the crank arms 68 can be adjusted using passive length-adjusting means (for example a screw or a turnbuckle) or active length- adjusting means (for example a mechanical or electromechanical or hydraulic linear actuator) 69.

Figure 2 shows an embodiment of a control system 110 for the variable-geometry bicycle simulator.

Preferably, this control system includes:

a central processing unit 90 arranged to process, in a known manner, data representative of a current position of the linear actuators in order to generate movement commands to be sent to said linear actuators to obtain the desired geometric configuration of the stationary bicycle, as better described below;

an interactive display 92 (preferably a touchscreen or pushbutton panel) connected to the central processing unit 90 and arranged to show the geometric configuration of the stationary bicycle;

an auxiliary keyboard 94 connected to the central processing unit 90 and arranged to provide said central processing unit 90 with auxiliary movement data for the linear actuators;

a control module 96 connected to the central processing unit 90 and arranged to control the movement of the linear actuators in order to obtain the desired geometric con- figuration of the stationary bicycle;

analogue sensors 98 arranged to detect the current position of the linear actuators;

A/D converters 100 arranged to convert the signals coming from the analogue sensors 98 to generate digital signals to be sent to the central processing unit 90 for subsequent processing.

Advantageously, alternatively or in addition to the analogue sensors 98 and to the A/D converters 100, there are digital sensors (not shown in the drawings) that are also arranged to acquire the current position of the linear actuators, and a digital interface arranged to receive the digital signals from the digital sensors and to forward them to the central process- ing unit 90 for subsequent processing.

In a first embodiment, the central processing unit 90 receives the position data from the analogue sensors 98 and calculates, in a known manner and on the basis of said position data and of the anthropometric and postural data of a given cyclist during pedalling, the desired geometric configuration of the stationary bicycle. On the basis of this desired configuration, it then generates movement commands that, via the control module 96, are ap- plied to the linear actuators in order to actuate the same and obtain the related movement.

In a second embodiment, a user may enter, using the auxiliary keyboard 92, the auxiliary movement data representing specific desired positions for the linear actuators, so that the central processing unit 90 generates movement commands calculated on the basis of these movement data received.

The central processing unit 90 can then calculate the desired geometric configuration of the stationary bicycle either solely on the basis of the position data and the anthropometric and postural measurements of a given cyclist during pedalling, or solely on the basis of the auxiliary movement data, or on the basis of the positional data, the anthropometric and postural measurements of a given cyclist during pedalling and the auxiliary movement data.

Furthermore, the control system 1 10 is also able to adjust the braking action of the brake 86 in the bottom bracket shell 82, so as to adjust the torque required to move the pedals at a given angular speed.

Various aspects and embodiments of an adjustable-geometry bicycle simulator according to the invention have been described. Advantageously, such a simulator enables fine and real-time adjustment of the geometry of any bicycle (road bicycle, track bicycle, BMX, mountain bike, city bike, etc.) by controlling the parameters required to achieve the best result for efficient pedalling by a specific cyclist.

It is intended that any embodiment may be combined with any other embodiment. Fur- thermore, the invention is not limited to the embodiments described, but may also vary within the scope defined by the attached claims.

Claims

1. Bicycle simulator, comprising an adjustable-geometry stationary bicycle (1) and a control system (1 10) for adjusting the geometry of the stationary bicycle (1),

wherein the stationary bicycle (1) comprises a frame (2), a saddle (14), a handlebar (12) and a pair of pedals (16),

wherein the frame (2) comprises a plurality of frame elements (22, 26, 30, 34, 38, 42, 46, 50) connected to each other by hinges (71, 72, 73, 74, 75, 76), and

wherein the control system (110) comprises at least one linear actuator (24, 28, 32, 36, 40, 44, 48, 52) able to change the length of a respective frame element (22, 26, 30, 34, 38, 42, 46, 50) along a given direction and a central processing unit (90) configured to control said at least one linear actuator (24, 28, 32, 36, 40, 44, 48, 52) to obtain the desired geometric configuration of the stationary bicycle.

2. Bicycle simulator according to claim 1 , wherein said respective frame element (22, 26, 30, 34, 38, 42, 46, 50) comprises two segments (22a and 22b, 26a and 26b, 30a and 30b, 34a and 34b, 38a and 38b, 42a and 42b, 46a and 46b, 50a and 50b) that are movable reciprocally along a given direction and wherein said at least one linear actuator (24, 28, 32, 36, 40, 44, 48, 52) is placed in series or in parallel with the two segments (22a and 22b, 26a and 26b, 30a and 30b, 34a and 34b, 38a and 38b, 42a and 42b, 46a and 46b, 50a and 50b).

3. Bicycle simulator according to claim 1 or claim 2, wherein the control system (1 10) further comprises adjusting means (56, 59) for adjusting the vertical position and the longi- tudinal position of the saddle (14), said adjusting means (56, 59) comprising a first and a second linear actuator (56, 59) controllable by the processing unit (90) to adjust the vertical position and the longitudinal position of the saddle (14), respectively.

4. Bicycle simulator according to any of the preceding claims, wherein the control system (1 10) further comprises adjusting means (79) for adjusting the inclination of the saddle (14).

5. Bicycle simulator according to any of the preceding claims, wherein the control system (110) further comprises adjusting means (62, 66) for adjusting the vertical position and the longitudinal position of the handlebar (12), said adjusting means (62, 66) comprising a first and a second linear actuator (62, 66) controllable by the central processing unit (90) for adjusting the vertical position and the longitudinal position of the handlebar (12), respectively.

6. Bicycle simulator according to any of the preceding claims, wherein the control system (110) further comprises adjusting means (77, 78) for adjusting the inclination of the handlebar (12).

7. Bicycle simulator according to any of the preceding claims, wherein the control system (1 10) is also configured to change the position of the hinges (71, 72, 73, 74, 75, 76) sequentially, by moving one hinge at a time, the movement of each hinge causing length changes and rotations of the frame elements (22, 26, 30, 34, 38, 42, 46, 50) connected thereto, but not movements of other hinges.

8. Bicycle simulator according to any of the preceding claims, wherein the axes of the hinges (71, 72, 73, 74, 75, 76) are substantially perpendicular to a sagittal vertical plane of the stationary bicycle (1) and are movable in said plane.

9. Bicycle simulator according to any of the preceding claims, wherein the hinges (71, 72, 73, 74, 75, 76) are idle hinges.

10. Bicycle simulator according to any of the preceding claims, wherein the frame elements (22, 26, 30, 34, 38, 42, 46, 50) comprise:

a first element (22) simulating the corresponding seat tube of a bicycle,

a second element (26) simulating the corresponding top tube of a bicycle, a third element (50) simulating the corresponding seat stay of a bicycle,

- a fourth element (46) simulating the corresponding chain stay of a bicycle,

a fifth element (34) simulating the corresponding oblique tube of a bicycle, a sixth element (38) simulating the corresponding fork (10) of a bicycle, a seventh element (30) simulating the corresponding head tube of a bicycle, and wherein said hinges (71, 72, 73, 74, 75, 76) include:

a first hinge (71) connecting said first element (22) to the second element (26) and to the third element (50),

- a second hinge (75) connecting said third element (50) to said fourth element (46) on the opposite side with respect to said first hinge (71),

a third hinge (74) connecting said first element (22) to said fourth element (46) and to said fifth element (34) on the opposite side with respect to said first hinge (71) and to said second hinge (75),

- a fourth hinge (73) connecting said fifth element (34) to said sixth element (38) and to said seventh element (30) on the opposite side with respect to said third hinge (74), a fifth hinge (72) connecting said seventh element (30) to said second element (26), on the opposite side with respect to said fourth hinge (73) and to said first hinge (71).

1 1. Bicycle simulator according to claim 10, comprising a first support (80) and a second support (81) for supporting the frame (2) of the bicycle, wherein said first support (80) is connected to said sixth element (38) by means of a sixth hinge (76) in such a manner that said sixth hinge (76) is constrained to move along a front-to-rear movement direction, and wherein said second support (81 ) is connected to said second hinge (75) in such a manner that said second hinge (75) is constrained to move along a front-to-rear movement direction.

12. Bicycle simulator according to any of the preceding claims, wherein the stationary bicycle (1) further comprises a bottom bracket shell (82) where two crank arms (68), ro- tatably connected to the pedals (16), are hinged in such a manner that said crank arms are connected to a brake (86) arranged to adjust the torque required to drive said crank arms (68).

13. Bicycle simulator according to claim 12, wherein the control system (1 10) further comprises length adjusting means (69) for adjusting the length of the crank arms (68).

14. Bicycle simulator according to any of the preceding claims, wherein the control system (1 10) further comprises:

a central processing unit (90) arranged to process data representative of a current position of the linear actuators (24, 28, 32, 36, 40, 44, 48, 52) in order to generate movement commands to be sent to said linear actuators (24, 28, 32, 36, 40, 44, 48, 52) to obtain the desired geometric configuration of the stationary bicycle,

an interactive display (92) connected to the central processing unit (90) and arranged to show the geometric configuration of the stationary bicycle,

an auxiliary keyboard (94) connected to the central processing unit (90) and arranged to provide said central processing unit (90) with auxiliary movement data for the linear actuators (24, 28, 32, 36, 40, 44, 48, 52),

a control module (96) connected to the central processing unit (90) and arranged to control the movement of the linear actuators (24, 28, 32, 36, 40, 44, 48, 52) in order to obtain the desired geometric configuration of the stationary bicycle,

analogue sensors (98) arranged to detect the current position of the linear actuators (24, 28, 32, 36, 40, 44, 48, 52), and

A/D converters (100) arranged to convert the signals coming from the analogue sensors (98) to generate digital signals to be sent to the central processing unit (90) for establishing the desired geometric configuration of the stationary bicycle.

15. Bicycle simulator according to claim 14, wherein the control system (1 10) is arranged to operate the linear actuators (24, 28, 32, 36, 40, 44, 48, 52) on the basis of a command by means of which the user defines which hinge (71, 72, 73, 74, 75, 76) to move along given directions and/or which frame element (22, 26, 30, 34, 38, 42, 46, 50) to lengthen or shorten.

16. Bicycle simulator according to claim 14 or claim 15, wherein the control system (1 10) is configured to calculate the most appropriate size of the frame (2) for a specific cyclist on the basis of the data collected by the analogue sensors (98).