MECHANICAL WALKING AND RUNNING SIMULATOR

Description

[0001] The present invention relates to a mechanical walking and / or running simulator.

[0002] It also relates to a method of simulating walking or running by controlling such a simulator.

[0003] In the fields of footwear design and manufacturing, it is often necessary to carry out wear tests "on wear" of a pair of shoes by a human user.

[0004] Indeed, these tests make it possible to observe the wear of the shoes as they are used and to identify, for example, the areas of the shoes which are subject to the greatest mechanical stress, in particular due to the friction of the shoes against the ground and the deformation of the foot during walking or running, and which are thus likely to be most quickly degraded.

[0005] Thanks to these observations, it is then possible to select and design pairs of shoes with particular geometries or materials, which are more resistant to the wear and deterioration observed.

[0006] Several methods exist for carrying out such extended use tests.

[0007] For example, it is possible to have a pair of shoes to be tested worn by a real human user for a long period: this method makes it possible to obtain reliable results (the shoes having undergone real use and having actually been subjected to prolonged mechanical stress), but has the disadvantages of requiring a very long study period and a significant number of human testers available.

[0008] It is also known to use gait simulators, which allow the movement of one or more human feet to be simulated during a walking or running cycle: these simulators thus make it possible to subject a pair of shoes to mechanical forces similar to those it would undergo if worn by a real human user.

[0009] Thanks to these simulators, it is possible to subject shoes to a large number of walking cycles in a limited time, simulating in a few days the wear they would exhibit if they had been worn by a real user for several months.

[0010] For example, document CN205093682U describes a walking simulator that can reproduce the movement of a shoe during a walking cycle, by moving it using an articulated arm relative to a platform representing the ground. However, the movement followed by the shoe in this simulator is very rudimentary and can only very roughly imitate a human walking cycle. The wear suffered by the shoe at the end of the tests will therefore not be representative of the actual wear it would have suffered if it had been worn by a human user: the results obtained from this simulator are therefore unreliable and therefore difficult to use.

[0011] Document US 4130007 A also describes a walking simulator for simulating a walking cycle.

[0012] Furthermore, existing mechanical simulators do not allow the simulation of a fast walking or running cycle requiring the reproduction of rapid and high-amplitude movements: it is therefore, for example, impossible to faithfully reproduce using these simulators the wear and tear experienced by a pair of sports shoes, usually worn for running.

[0013] The present invention thus aims to resolve the aforementioned drawbacks, by proposing a walking simulator making it possible to faithfully reproduce a human walking cycle.

[0014] Another objective of the invention is to propose a walking simulator which makes it possible to reproduce several different walking cycles by varying the walking speed, the type of attack and placement of the foot or even the nature of the ground.

[0015] Yet another objective of the invention is to provide a walking simulator which makes it possible to reproduce a running or walking cycle at fast speed.

[0016] For this purpose, it offers a walking simulator, including: an articulated mechanical foot, a first movement system adapted to move said articulated mechanical foot in a movement combining a translational movement in a horizontal direction and a rotational movement around a transverse direction, orthogonal to said horizontal direction, a platform having an upper surface adapted to come into contact with the articulated mechanical foot, a second movement system, adapted to move said platform in translation in a vertical direction, orthogonal to the horizontal direction and to the transverse direction, the first movement system and the second movement system being designed to be driven independently or interpolated, so that the movement of the articulated mechanical foot relative to the platform is similar to that of a human foot relative to the ground during a walking or running cycle.

[0017] Such a walking simulator makes it possible to effectively reproduce a human walking movement, thanks to the joint control of the first movement system and the second movement system.

[0018] Indeed, the first movement system makes it possible to drive the articulated mechanical foot in a movement simulating the movement of a human leg during the phase of a walking cycle during which the foot is not in contact with the ground (“swing phase”): during the reproduction of this swing phase by the simulator, the articulated mechanical foot is not in contact with the upper surface of the platform.

[0019] During this oscillating phase, the articulated mechanical foot follows a movement obtained by the combination of a translational movement in the horizontal direction and a rotational movement around the transverse direction.

[0020] By controlling the second movement system in a coordinated manner with the control of the first movement system, driving the platform in a translational movement in the vertical direction, it is possible to simulate the phase of the walking cycle during which the foot is in contact with the ground (“support phase”): during this support phase, the articulated mechanical foot is in contact with the upper surface of the platform.

[0021] Bringing the platform into contact with the articulated mechanical foot makes it possible to modify the movement imposed on the latter by the first movement system, the second movement system also driving the articulated mechanical foot in a translational movement in the vertical direction.

[0022] The coordinated control of the first movement system and the second movement system therefore makes it possible to drive the articulated mechanical foot in a movement comprising at least three independent degrees of freedom and thus to reproduce the complex movement of a human foot during a walking cycle.

[0023] It should be noted that the movement simulating the gait cycle is the movement of the articulated mechanical foot relative to the platform.

[0024] The quality of the simulation of the walking cycle using the walking simulator according to the invention thus depends on the joint control of the first movement system and the second movement system: in order to ensure that the movement of the articulated mechanical foot properly reproduces the movement of a foot during a walking or running cycle, it is possible to base the parameterization of the first movement system and the second movement system on a set of experimental data making it possible to describe the kinematics of the movement of a human foot during walking or running as well as its dynamic parameters.

[0025] This dataset may, for example, be obtained from observations of the walking or running cycle of real human subjects and include data on position, speed, acceleration, forces, pressure, etc.

[0026] The parameterization of the first movement system and the second movement system can thus be carried out in such a way that the movement of the articulated mechanical foot is described by the same set of experimental data: in other words, if one were to carry out, during a walking cycle thus simulated by the walking simulator, the same measurements as those having been carried out during a real walking cycle, all of these measured data would then be identical to all of the experimental data having been used to parameterize the first movement system and the second movement system.

[0027] According to one possibility, the articulated mechanical foot is adapted so that it can be "fitted" with a shoe to be tested: after several walking cycles, it is thus possible to observe the state of wear of this shoe, for example the loss of material at the level of its sole or its lateral deformations, this state of wear then being representative of the state of wear resulting from prolonged use of this shoe by a real human user.

[0028] According to the invention, the first movement system comprises an intermediate part having: a first end fixed to the articulated mechanical foot and a second end fixed to a carriage, movable in the horizontal direction, by means of a pivot connection in the transverse direction.

[0029] This intermediate piece thus simulates the role of a human tibia and this carriage that of the end of a human femur, the pivot connection connecting the intermediate piece to the carriage then simulating the articulation of a human knee.

[0030] The carriage is movable in the horizontal direction, for example along guides arranged in this same horizontal direction, and the position of the carriage therefore reproduces the position of a human knee during the walking cycle.

[0031] However, in a real walking cycle the movement of the knee does not follow a pure rectilinear translational movement: it is thus the movement of the carriage relative to the platform (itself being movable in the vertical direction) which reproduces the movement of a human knee.

[0032] According to the invention, the first movement system comprises a connecting rod / crank system designed to move the carriage in the horizontal direction, the crank being movable in rotation around the transverse direction.

[0033] This characteristic, in addition to presenting advantages in terms of simplicity of realization, presents a great robustness and makes it possible to impose on the trolley movements of large amplitude and at high speed, inaccessible to other walking simulators of the state of the art without significant risk of degradation. In particular, it is thus possible to simulate, thanks to the walking simulator according to the invention, running or fast walking cycles, inaccessible to walking simulators of the state of the art.

[0034] The position of the carriage in the horizontal direction is then determined by the rotational movement of the crank.

[0035] According to the invention, the first movement system comprises: a geared motor designed to drive the intermediate part in a rotational movement about the transverse direction, and a motor designed to drive the crank in a rotational movement about the transverse direction, this motor and this geared motor can be controlled independently of each other. The control of these two motors thus makes it possible to control the position of the carriage according to the horizontal direction and the inclination of the intermediate part in relation to the vertical direction, that is to say to simulate the position of the knee and that of the tibia during the walking cycle.

[0036] The motor driving the connecting rod / crank system can advantageously be of the “brushless” type and have an adjustable fixed rotation speed.

[0037] According to one possibility, the crank includes one or more balancing masses to attenuate the mechanical vibrations induced by its movement.

[0038] Advantageously, the connecting rod is fixed to the crank at an adjustable distance from the latter's axis of rotation.

[0039] In this way, it is possible to modify the movement of the carriage in the horizontal direction, without modifying the characteristics of the rotational movement of the crank around the transverse direction.

[0040] In one embodiment, the articulated mechanical foot comprises a central body fixed to the first end of the intermediate part by means of a mechanical connection allowing a rotational movement, around the transverse direction, of said central body relative to said first end, so as to simulate the articulation of an ankle of a human foot.

[0041] According to one characteristic, the articulated mechanical foot comprises a front part fixed to the central body by means of a mechanical connection allowing a rotational movement, around the transverse direction, of said front part relative to said central body, so as to simulate the metatarsophalangeal joints of a human foot.

[0042] This structure of the articulated mechanical foot, based on an anatomical model of a real human foot and featuring two additional joints, makes it possible to simulate a walking or running cycle even more faithfully, taking into account the deformations undergone by a human foot during this cycle, particularly during the support phase.

[0043] Thanks to these joints, the articulated mechanical foot is deformed when it comes into contact with the platform and is rotated relative to the intermediate part.

[0044] For example, it is conceivable that the mechanical connections connecting the central body to the front part of the articulated mechanical foot and to the first end of the intermediate part are pivot connections in the transverse direction.

[0045] The movement of the articulated mechanical foot thus comprises five degrees of freedom (translation of the carriage, rotation of the intermediate part, translation of the platform, rotation of the central body and rotation of the front part): it is thanks to this high number of degrees of freedom that the simulator according to the invention allows a better reproduction of a walking cycle.

[0046] It is possible to control the relative movements of the central body, the front part and the intermediate part using an interpolated control system, in order to further refine the simulation of the gait cycle and make it as close as possible to a real gait cycle.

[0047] In one embodiment, the second drive system is configured to independently drive: the position of the platform in the vertical direction, and the pressure exerted by the platform on the articulated mechanical foot when the articulated mechanical foot is in contact with the upper surface of the platform.

[0048] According to one possibility, the second drive system comprises: a rack and pinion system for controlling the position of the platform in the vertical direction, and a pneumatic cylinder for controlling the pressure exerted by the platform on the articulated mechanical foot when the articulated mechanical foot is in contact with the upper surface of the platform.

[0049] This dual control of the vertical position of the platform and the pressure it exerts on the articulated mechanical foot makes it possible to simulate both the position of the ground in relation to the foot and the force with which the foot comes into contact with the ground during the walking cycle.

[0050] The simulation of the intensity of this force is essential because it determines the wear of the shoe at the level of the contact zone between it and the ground, but also the violence of the deformations generally undergone by the shoe: the combination of the control of the rack system and the pneumatic cylinder therefore makes it possible to faithfully simulate the mechanical effects of the impact of the shoe against the ground during the support phase of the walking cycle.

[0051] According to one embodiment, the second movement system is configured to move the platform in translation in the vertical direction, orthogonal to the horizontal direction and to the transverse direction, and in rotation around a supination / pronation steering axis, the supination / pronation steering axis being orthogonal to the transverse direction.

[0052] According to these provisions, the walking simulator makes it possible to alternately simulate a posture of supination or pronation of the foot in contact with the ground during the walking cycle.

[0053] According to one embodiment, a length of the intermediate piece is adjustable. According to these arrangements, the length of the tibia can be adapted to the thickness of the sole of the shoe tested, without modifying the trajectory of the platform.

[0054] According to one characteristic, the platform and / or the articulated mechanical foot include measuring instruments for measuring the mechanical forces exerted by the articulated mechanical foot on the platform.

[0055] It is also possible to place measuring instruments in the shoe to be tested.

[0056] Alternatively, the upper surface of the platform has a removable and changeable covering, so as to simulate walking on surfaces of different types.

[0057] For example, it is possible to vary the hardness of the ground or its grip.

[0058] The invention also relates to a method for simulating walking using a walking simulator as previously described, said method comprising at least the following steps: obtaining a set of experimental data making it possible to describe the kinematics and dynamics of the movement of a human foot during walking or running, and controlling the first movement system and the second movement system, so that the kinematics of the movement of the articulated mechanical foot relative to the platform is also described by said set of experimental data.

[0059] According to the invention, the method also comprises the following independent steps: controlling the rotational movement of the crank around the transverse direction, controlling the rotational movement of the intermediate part relative to the carriage around the transverse direction, controlling the position of the platform in the vertical direction, and controlling the pressure exerted by the platform on the articulated mechanical foot when the articulated mechanical foot is in contact with the upper surface of the platform.

[0060] Other characteristics and advantages of the present invention will appear on reading the detailed description below, of several non-limiting examples of implementation, made with reference to the appended figures in which: [ Fig.1 ] is a view of a walking simulator according to the invention, [ Fig.2 ] is a detailed view of the articulated mechanical foot, [ Fig.3 ] is a schematic view of the initial configuration of a walking cycle, [ Fig.4 ] is a schematic view of the stance phase of a gait cycle, [ Fig.5 ] is a schematic view of the stance phase of a gait cycle, [ Fig.6 ] is a schematic view of the stance phase of a gait cycle, [ Fig.7 ] is a schematic view of the stance phase of a gait cycle, [ Fig.8 ] is a schematic view of the swing phase of a gait cycle, [ Fig.9 ] is a schematic view of the swing phase of a gait cycle, [ Fig.10 ] is a schematic view of a platform according to an embodiment of the simulator making it possible to simulate supination during a gait cycle, [ Fig.11 ] is a schematic view of a platform according to an embodiment of the simulator for simulating pronation during a gait cycle, [ Fig.12 ] is a schematic view of one embodiment of an adjustable tibia

[0061] There figure 1 represents a walking simulator 1 according to the invention, during the support phase.

[0062] This walking simulator 1 comprises an articulated mechanical foot 2 connected to a first end 31 of an intermediate part 3 by a pivot connection 21: the articulated mechanical foot 2 can therefore describe a rotational movement relative to the intermediate part 3 around a transverse direction (not shown).

[0063] The articulated mechanical foot 2 is also fitted with a shoe 20, the walking simulator 1 of which makes it possible to simulate the wear during a walking or running cycle.

[0064] The intermediate part 3 is furthermore fixed, at its second end 32 to a carriage 4 by means of a pivot connection 33: the intermediate part 3 can therefore describe, under the action of a geared motor 34, a rotational movement relative to the carriage 4 around the transverse direction.

[0065] This carriage 4 is movable in the horizontal direction 41, along guides 42 having a longitudinal direction parallel to the horizontal direction 41, under the action of a connecting rod / crank system comprising a connecting rod 5 and a crank 6.

[0066] The connecting rod 5 is connected respectively to the carriage 4 and to the crank 6 by the pivot links 51 and 52 in the transverse direction.

[0067] The crank 6 can describe, under the action of a motor 62 (not shown), a rotational movement around the axis 61, collinear with the transverse direction.

[0068] This rotational movement of the crank 6 mechanically causes a translational movement of the carriage 4 in the horizontal direction.

[0069] The crank 6 also includes a balancing mass 63 making it possible to limit the intensity of the internal vibrations caused by the movement of the crank 6, the connecting rod 5, the carriage 4, and the intermediate part 3.

[0070] The walking simulator 1 also comprises a platform 7 having an upper surface 71 in contact with the shoe 20.

[0071] This platform 7 is movable in translation in a vertical direction 72 along guides 73, under the action of a rack system 74 and a pneumatic cylinder 75.

[0072] There figure 2 represents the detailed structure of the articulated mechanical foot 2.

[0073] This articulated mechanical foot 2 comprises a central body 22 and a front part 23, the central body being respectively connected to the intermediate part 3 by a pivot connection 21 and to the front part by a pivot connection 24.

[0074] The two pivot links 21 and 24 allow relative rotational movements around the transverse direction of the intermediate part 3, the central body 22 and the front part 23.

[0075] It will be noted that, in other embodiments not shown, the pivot link 21 and the pivot link 24 can be replaced by mechanical links allowing relative movements of the intermediate part 3, the central body 22 and the front part 23 comprising more degrees of freedom: such links making the articulated mechanical foot 2 closer to the anatomy of a real human foot, they make it possible to simulate a walking or running cycle closer to a real walking or running cycle.

[0076] For example, pivot link 21 and pivot link 24 can be replaced by ball-and-socket type links.

[0077] The different elements of the walking simulator 1 thus each represent an element of the anatomy of a human foot and leg, and their relative movements make it possible to simulate a complete walking or running cycle.

[0078] In particular, the articulated mechanical foot 2 represents a human foot, the pivot connection 33 represents a knee, the intermediate piece 3 represents a tibia, the pivot connection 21 represents the articulation of an ankle, the pivot connection 24 represents the metatarsophalangeal articulation of a foot, and the platform 7 represents a ground, on which the foot is brought to rest.

[0079] The simulation of a walking or running cycle can thus be controlled by the coordinated control of the motor 62, the geared motor 34, the rack system 74 and the pneumatic cylinder 75.

[0080] The control of these four elements, associated with the two passive articulations represented by the pivot links 21 and 24, makes it possible to faithfully reproduce a human walking or running cycle: the movement of the articulated mechanical foot 2 (or of the shoe 20) relative to the platform 7 presents kinematics identical to the movement of a human foot relative to the ground during a walking or running cycle.

[0081] It should be noted that although this rack system 74 and this pneumatic cylinder 75 both serve to move the platform 7 in the vertical direction 72, they each have a distinct role: the rack system 74 makes it possible to control the position of the platform 7 in the vertical direction 72, thus simulating the position of the ground relative to the foot, and the pneumatic cylinder 75 makes it possible to control the pressure exerted by the platform 7 on the shoe 20 when they are in contact with each other, thus simulating the impact force of the foot against the ground during the support phase.

[0082] THE figures 3 à 9 The following illustrate the different successive phases of an example walking cycle simulated using the walking simulator 1.

[0083] As previously described, the transition from one of these phases to the next is carried out by controlling the following four parameters: the angle α, identifying the position of the pivot connection 52 relative to the horizontal direction 41 and characterizing the rotational movement of the crank 6 around the transverse direction, the angle β, characterizing the inclination of the intermediate part 3 relative to the vertical direction 72, the height H of the platform 7, and the pressure P of the pneumatic cylinder 75.

[0084] The numerical values presented below for these four parameters are given here only as a non-limiting example.

[0085] There figure 3 represents the initial position of the gait cycle.

[0086] On this figure 3 , α = 0°, β = -10°, H = 40 mm, and P = 0 mbar.

[0087] In this initial position, the articulated mechanical foot 2 is not in contact with the upper surface 71 of the platform 7 and therefore follows a movement resulting from the combination of a translation in the horizontal direction 41 (displacement of the carriage 4) and rotation around the transverse direction (rotation of the intermediate part 3 relative to the carriage 4).

[0088] There figure 4 represents the start of the stance phase.

[0089] On this figure 4 , α = 45°, β = -2°, H = 110 mm, and P = 1500 mbar.

[0090] Here, the articulated mechanical foot 2 is in “flat” contact with the upper surface 71 of the platform 7: the central body 22 and the front part 23 are simultaneously supported on the upper surface 71.

[0091] THE figures 5 à 7 following also illustrate the support phase, during which the articulated mechanical foot 2 is in contact with the platform 7.

[0092] On these different figures: α = 90°, β = 13°, H = 150 mm, and P = 1500 mbar ( figure 5 ), α = 135°, β = 37°, H = 170 mm, and P = 1500 mbar ( figure 6 ), α = 180°, β = 60°, H = 180 mm, and P = 1500 mbar ( figure 7 ),

[0093] During this support phase, the articulated mechanical foot 2 remains in contact with the platform 7 and the measurements of the angles α and β increase: this reflects the displacement of the tibia (intermediate piece 3) and the knee (pivot connection 33) relative to a foot (articulated mechanical foot 2) stationary on the ground (platform 7).

[0094] It will be noted that this movement, associated with the elevation of the platform 7, has the consequence of deforming the articulated mechanical foot 2 and causing it to rotate relative to the intermediate part 3.

[0095] In addition, this movement modifies the contact between the articulated mechanical foot 2 and the platform 7.

[0096] Indeed, on the figure 5 , the central body 22 and the front part 23 are simultaneously supported on the upper surface 71, while on the figures 6 And 7 , only the front part 23 is still in contact: this reflects the elevation of the heel and the transfer of support to the front of the foot (central part 23).

[0097] During the entirety of this support phase, the pressure P of the pneumatic cylinder 75 has a high value, reproducing the intensity of the contact force between the foot (articulated mechanical foot 2) and the ground (platform 7) during this support phase.

[0098] THE figures 8 And 9 The following illustrate the swing phase of the walking cycle, during which the articulated mechanical foot 2 is no longer in contact with the platform 7.

[0099] In these figures: α = 225°, β = 60°, H = 40 mm, and P = 0 mbar ( figure 8 ), α = 315°, β = -6°, H = 40 mm, and P = 0 mbar ( figure 9 ).

[0100] During this oscillating phase, the measurement of the angle α continues to increase while that of the angle β decreases: this reflects a movement of the knee (pivot connection 33) and the tibia (intermediate piece 3) with a view to repositioning in the initial configuration represented by the figure 3 and the beginning of a new walking cycle.

[0101] The value of the pressure P remains zero because there is no contact between the foot (articulated mechanical foot 2) and the ground (platform 7).

[0102] The coordinated control of the parameters α, β, H and P (respectively thanks to the motor 62, the geared motor 34, the rack system 74 and the pneumatic cylinder 75) therefore makes it possible to precisely simulate a human walking cycle.

[0103] Furthermore, by varying the values of these parameters relative to each other, it is possible to modify the simulated gait cycle and thus test the wear of shoes under different conditions.

[0104] For example, by increasing the speed of variation of the angle α, it is possible to simulate a faster walking cycle.

[0105] Similarly, by increasing the value of pressure P, it is possible to simulate a gait cycle with a greater ground impact force.

[0106] Finally, it is possible to adjust the distance D between the pivot connection 52 relative to the axis 61 around which the crank 6 is rotating: reducing the distance D causes the amplitude of the movement of the carriage 4 to decrease in the horizontal direction 41 and thus makes it possible to simulate a walking cycle with a shorter stride.

[0107] According to an embodiment illustrated in figures 10 And11 , the platform 7 of the walking simulator is connected to a support 26, the support 26 being actuated in translation in the vertical direction 72 along the guides 73, under the action of the rack system 74 and the pneumatic cylinder 75; the connection between the platform 7 and the support 26 is a supination / pronation control axis 25, said supination / pronation control axis 25 having a direction transverse to a vertical plane of the support 26, and transverse to the axes of the pivot connections 33, 21, and 24 illustrated in the figures 1 And 2; the platform 7 is rotatable about the supination / pronation steering axis 25, and actuated in rotation about this axis by a supination / pronation steering motor, between two extreme angular positions on either side of a median position corresponding to the horizontal position of the platform 7. The platform 7 is thus both driven by the translational movement of the support 26, under the action of the rack system 74 and the pneumatic cylinder 75, and in rotation about the supination / pronation steering axis 25, so as to simulate a gait according to an alternation of supination and pronation postures. Thus, for example, the simulation of a supination posture can be obtained with an inclination of the platform 7 of + 20° above the horizontal median position towards one side of the machine, transversely to the direction of the simulated walking, as shown in dotted lines on the figure 10 , and, alternatively, the simulation of a pronation posture can be obtained with an inclination of the platform 7 of -20° below the horizontal median position towards the opposite side of the machine, transversely to the direction of simulated walking, as shown in dotted lines on the figure 11 .

[0108] Furthermore, and in a complementary manner, the intermediate piece 3 may have an adjustable length, as illustrated in the figure 12 ; for this, for example, the intermediate part 3 may comprise an adjustment part 33 at its second end 32, said adjustment part being configured to allow the second end 32 to be moved in or out more or less from the intermediate part 3.

Claims

1. A walking simulator (1), including: - an articulated mechanical foot (2), - a first displacement system adapted to move said articulated mechanical foot (2) in a movement combining a translational movement in a horizontal direction (41) and a rotational movement about a transverse direction, orthogonal to said horizontal direction (41), - a platform (7) having an upper surface (71) adapted to come into contact with the articulated mechanical foot (2), - a second displacement system, adapted to move said platform (7) in translation in a vertical direction (72), orthogonal to the horizontal direction (41) and to the transverse direction, the first displacement system and the second displacement system being designed to be controlled in an independent or interpolated manner, so that the movement of the articulated mechanical foot (2) relative to the platform (7) is similar to that of a human foot relative to the ground during a walking or running cycle, wherein the first displacement system includes an intermediate part (3) having: - a first end (31) fastened to the articulated mechanical foot (2) and - a second end (32) fastened to a carriage (4), movable in the horizontal direction (41), via a pivot connection (33) in the transverse direction, wherein the first displacement system includes a connecting rod / crank system (5, 6) designed to move the carriage (4) in the horizontal direction (41), the crank (6) being movable in rotation about the transverse direction, wherein the first displacement system includes: - a gear motor (34) designed to drive the intermediate part (3) in a rotational movement about the transverse direction, and - a motor (62) designed to drive the crank (6) in a rotational movement about the transverse direction, this motor (62) and this gear motor (34) being able to be controlled independently of each other.

2. The walking simulator (1) according to claim 1, wherein the crank (6) includes one or several balance weights (63) making it possible to attenuate the mechanical vibrations induced by the movement thereof.

3. The walking simulator (1) according to claim 2, wherein the connecting rod (5) is fastened to the crank at an adjustable distance (D) from the axis (61) of rotation of the latter.

4. The walking simulator (1) according to any one of the preceding claims, wherein the articulated mechanical foot (2) includes a central body (22) fastened to the first end (31) of the intermediate part (3) via a mechanical connection (21) allowing a rotational movement, about the transverse direction, of said central body (22) relative to said first end (31), so as to simulate the ankle joint of a human foot.

5. The walking simulator (1) according to the preceding claim, wherein the articulated mechanical foot (2) includes a front portion (23) fastened to the central body (22) via a mechanical connection (24) allowing a rotational movement, about the transverse direction, of said front portion (23) relative to said central body (22), so as to simulate the metatarsophalangeal joints of a human foot.

6. The walking simulator (1) according to any one of the preceding claims, wherein the second drive system is designed to independently control: - the position of the platform (7) in the vertical direction (72), and - the pressure exerted by the platform (7) on the articulated mechanical foot (2) when the articulated mechanical foot (2) is in contact with the upper surface (71) of the platform (7).

7. The walking simulator (1) according to the preceding claim, wherein the second drive system includes: - a rack and pinion system (74) making it possible to control the position of the platform (7) in the vertical direction (72), and - a pneumatic cylinder (75) making it possible to control the pressure exerted by the platform (7) on the articulated mechanical foot (2) when the articulated mechanical foot (2) is in contact with the upper surface (71) of the platform (7).

8. The walking simulator (1) according to any one of the preceding claims, wherein the second drive system is configured to move the platform (7) in rotation about a supination / pronation control axis (25), the supination / pronation control axis (25) being orthogonal to the transverse direction,9. The walking simulator (1) according to any one of the preceding claims, wherein the platform (7) and / or the articulated mechanical foot (2) include measuring instruments making it possible to measure the mechanical forces exerted by the articulated mechanical foot (2) on the platform (7).

10. The walking simulator (1) according to any one of the preceding claims, wherein the upper surface (71) of the platform (7) has a removable and changeable coating, so as to simulate walking on different types of surfaces.

11. A method for simulating walking by means of a walking simulator (1) according to any one of the preceding claims, said method including at least the following steps: - obtaining a set of experimental data making it possible to describe the kinematics of the movement of a human foot during walking or running, and - controlling the first displacement system and the second displacement system, such that the kinematics of the movement of the articulated mechanical foot (2) relative to the platform (7) is also described by said set of experimental data, wherein the walking simulator (1) is according to claims 1 to 10, said method including the following independent steps: - controlling the rotational movement of the crank (6) about the transverse direction, - controlling the rotational movement of the intermediate part (3) relative to the carriage (4) about the transverse direction, - controlling the position of the platform (7) in the vertical direction (72), and - controlling the pressure exerted by the platform (7) on the articulated mechanical foot (2) when the articulated mechanical foot (2) is in contact with the upper surface (71) of the platform (7).