Omnidirectional powertrain for motion simulation

Abstract

Omnidirectional drive unit for motion simulation. The invention relates to a drive unit based on the omnidirectional wheel concept (4). Several of these drive units used in conjunction allow a motion platform to be given the degrees of freedom Tx, Ty, and yaw. Each drive unit includes a connection interface (7) designed to be connected to a motion platform in general, and in particular to a chassis made of extruded aluminum profiles. Figure to be published with the abstract: Figure 3

Description

Title of the invention: Omnidirectional powertrain for motion simulation. Technical field of the invention

[0001] In general, the present invention relates to devices capable of simulating movement. These devices can subject a user to certain real or simulated, prolonged or transient accelerations, while keeping the user in a controlled and safe environment.

[0002] In particular, the present invention relates to motion simulators for land or air vehicles. State of the art

[0003] PC simulations of motor racing and aviation have encouraged the rise of dedicated peripherals and accessories such as force feedback steering wheels, joysticks, brake and accelerator pedals, rudder pedals, seats, etc.

[0004] In order to recreate the layout of a racing car or aircraft cockpit, chassis designed to ergonomically and adjustablely arrange these peripherals and accessories have become popular. The rigid structure of these chassis provides a stable seat for the pilot and allows them to withstand the forces exerted on the controls without deforming. These chassis are traditionally static.

[0005] Motion simulation solutions have been developed to transform these static chassis into dynamic chassis, in order to increase the realism of the experience by subjecting the user to movements generated by the simulation.

[0006] A type of motion simulator, relatively common among the general public, consists of an arrangement of four electric cylinders or linear actuators installed near the four vertices of a rectangular frame, each actuator having a certain vertical travel. By extending these actuators in a differentiated or uniform manner, it is possible to achieve three degrees of freedom: roll, pitch, and ascent.

[0007] This type of motion simulator can satisfactorily reproduce vertical accelerations due to road texture, vibrations, suspension work, chicane edges, etc. But their ability to simulate horizontal accelerations is not optimal.

[0008] Indeed, for these horizontal accelerations, this type of motion simulator uses the known technique of tilting along the roll and / or pitch axes, in order to exploit the ambiguity between gravity and inertial force. However, the roll and pitch rotation axes of this type of simulator are generally close to the ground and therefore far from the user's head. Each pitch or roll rotation The chassis movement is thus accompanied by an unwanted translational movement of the user's head. As a result, the user experiences incorrect transient effects in their inner ear, which detract from the realism of the simulation.

[0009] Another motion simulation technology based on the omnidirectional wheel is mentioned in FR2402922. This technology natively provides the degrees of freedom Tx (surge), Ty (sway), and yaw. One advantage of this motion simulation technology is that it avoids the incorrect transient effects discussed previously.

[0010] The omnidirectional wheel was initially described in 1919 in US1305535. The mecanum wheel is a type of omnidirectional wheel. The mecanum wheel was initially described in 1972 in US3876255A.

[0011] Document KR20230102129A mentions a two-stage motion simulator, one of the stages of which is based on the omnidirectional wheel.

[0012] In documents FR2402922 and KR20230102129A mentioned above, the part of the motion simulator providing the degrees of freedom Tx, Ty, and yaw is an integral part of the motion platform. It would be advantageous to have the ability to easily install or uninstall such a motion simulator. In particular, it would be advantageous for the motion simulator to be composed of several modules, each with a connection interface designed for connection to various types of motion platforms.

[0013] Improvement possibilities thus exist in the form of a modular motion simulator based on the omnidirectional wheel allowing a static chassis to be transformed into a dynamic chassis and giving it the degrees of freedom Tx, Ty and yaw.

[0014] More generally, a notable improvement would be a modular motion simulator that can be connected to and give to any motion platform the degrees of freedom Tx, Ty and yaw.

[0015] The applicant has designed, implemented, tested and improved the present invention through several iterations in order to overcome the shortcomings of the state of the art and establish new advantages. Presentation of the invention

[0016] The present invention consists of an omnidirectional drive unit for motion simulation, which can be easily connected to a motion platform via a connection interface. Several of these omnidirectional drive units operating together can give a motion platform the ability to move according to the degrees of freedom Tx, Ty, and yaw.

[0017] Each omnidirectional powertrain includes at least one omnidirectional wheel.

[0018] It is understood that the term omnidirectional wheel refers to all types of omnidirectional wheels, including the mecanum wheel.

[0019] In a broad sense, a motion platform refers to any physical platform on which a person can stand and which is capable of simulating movements, often synchronized with visual or auditory elements, to create an immersive experience. Structural rigidity is an important characteristic of a motion platform, due to the accelerations to which it will be subjected.

[0020] In particular, one of the objectives of the invention is to easily convert a static chassis composed of extruded aluminum profiles into a dynamic chassis having the degrees of freedom Tx, Ty and yaw thanks to several omnidirectional powertrains having a connection interface adapted to this type of chassis.

[0021] Extruded aluminum profiles having a plurality of grooves were initially described in US3143981. These profiles can be connected to each other in particular by means of sliding fasteners adapted to the grooves of these profiles, such as T-slot nuts.

[0022] Thus, each powertrain may include a connection interface configured for connection with a motion platform in general, or for this type of chassis made of extruded aluminum profiles in particular.

[0023] To this end, an object of the invention is a powertrain comprising, an engine; a mechanical reduction means functionally connected to said engine; a mechanical power transmission means having an input and an output, said input being functionally connected to said mechanical reduction means; an omnidirectional wheel functionally connected to said output of said mechanical power transmission means, said omnidirectional wheel being in contact with the ground or a base; a support frame rigidly connecting the non-moving parts of said engine, said mechanical reduction means and said mechanical power transmission means, creating a complete connection between said non-moving parts; said powertrain being characterized in that said powertrain is configured for use in motion simulation to move a user from a motion platform relative to the ground or relative to a base, whereby said powertrain further comprises a connection interface configured for connection with a motion platform, said connection interface being connected to said support frame of said powertrain.

[0024] Another object of the invention is a powertrain comprising, an engine having an engine casing; a gearbox having a gearbox casing, said gearbox being functionally connected to said engine, said gearbox casing and said engine casing being in complete connection, forming a rigid engine-gearbox assembly; a drive shaft having one of its ends functionally connected to said gearbox; an omnidirectional wheel functionally connected to said drive shaft, said omnidirectional wheel being in contact with the ground or a base; at least one bearing housing having a mounting base, said bearing housing(s) being functionally connected to said drive shaft, in a pivot connection;a support frame rigidly connecting said engine-gearbox assembly and said mounting plates of said bearing(s), creating a complete connection between said support frame, said engine-gearbox assembly and said mounting plates of said bearing(s); said powertrain being characterized in that, said powertrain is configured for use in motion simulation to move a user from a motion platform relative to the ground or relative to a base, whereby said powertrain further comprises a connection interface configured for connection with a motion platform, said connection interface being connected to said support frame of said powertrain.

[0025] In one embodiment, said connection interface is configured to be connected to a movement platform having a chassis made of extruded metal profiles, said extruded metal profiles having a plurality of grooves.

[0026] In another embodiment, said connection interface is configured to be connected to a movement platform having a chassis made of tubular metal elements.

[0027] In another embodiment, said connection interface is configured to be connected to a movement platform consisting of at least a partial replica of a vehicle.

[0028] In another embodiment, said connection interface is configured to be connected to a movement platform consisting of a seat.

[0029] In another embodiment, said connection interface is connected to the powertrain in a removably manner to said support frame of said group.

[0030] In another embodiment, said connection interface comprises several perforations arranged in a square or rectangular pattern, one of the center distances of said perforation pattern having a length of 4 cm, or a multiple of 4 cm.

[0031] In another embodiment, said support frame further includes, an attachment point for a stabilizer bar; a stabilizer bar functionally connected to said attachment point, said stabilizer bar being configured to be connected to another powertrain.

[0032] In another embodiment, said connection interface further includes, an attachment point for a stabilizer bar; a stabilizer bar functionally connected to said attachment point, said stabilizer bar being configured to be connected to another powertrain. Description of the figures

[0033] Other features and advantages of the invention will become apparent from the detailed description of the following non-limiting examples, for the understanding of which reference should be made to the accompanying drawings, among which:

[0034] [Fig-1] is a perspective view of a complete omnidirectional powertrain with its connection interface.

[0035] [Fig.2] is a front view of an omnidirectional powertrain.

[0036] [Fig.3] is a perspective view illustrating the typical installation of four groups omnidirectional powertrains on a motion platform consisting of a chassis made of extruded aluminum profiles.

[0037] [Fig.4] is a perspective view detailing the attachment of an omnidirectional powertrain to an aluminum profile.

[0038] [Fig.5] is a perspective view of a removable connection interface.

[0039] [Fig.6] is a front view of two connected omnidirectional powertrains between them by a stabilizer bar. The attachment points of this stabilizer bar are located on the support frames.

[0040] [Fig.7] is a front view of powertrains installed on a replica vehicle. Detailed description of the invention

[0041] The mecanum wheel (4) is selected as the omnidirectional wheel type. Four drive groups based on the mecanum wheel are to be provided to make a motion platform (P) dynamic and give it the degrees of freedom Tx, Ty and yaw.

[0042] Two types of drive units are used: those for the right side of the movement platform will have a mecanum wheel (4) having a certain topology, while for the left part will have a mecanum wheel (4) having a "mirror" topology.

[0043] The algorithm for obtaining omnidirectional movement using four mecanum wheels is known in the prior art.

[0044] The first design decision that a person skilled in the art must make is the determination of the necessary motor power based on fundamental parameters such as the total mass to be moved and the desired maximum acceleration, this maximum acceleration depending on the type of vehicle to be simulated.

[0045] Another design decision will be the size of the mecanum wheels (4) to be selected, which will depend on the mass to be moved and the desired maximum speed.

[0046] In a powertrain, the engine output shaft (1) is connected to the gearbox (2). The gearbox and engine housings are joined by connecting elements (not shown) to form an engine-gearbox assembly.

[0047] The transmission shaft (3) is supported by two bearings (3R) and is connected on one side to the output of the gearbox (2), and on the other side to the mecanum wheel (4).

[0048] The support frame (6) allows the non-moving parts of the powertrain to be joined together, in particular in this embodiment, the gearbox casing (2) which is in complete connection with the engine casing (1), as well as the bearing mounting bases (3R).

[0049] The connection interface (7) can be an integral part of the support frame (6), or be removably connected to it. A removable connection interface (7) has been selected in this embodiment, facilitating installation on the movement platform (P).

[0050] Thanks to their respective connection interface (7), each of the four powertrain groups is connected to the movement platform (P), which here is a chassis made of extruded aluminum profiles, using suitable fixing elements.

[0051] The powertrains are positioned so that the points of contact between the mecanum wheels (4) and the ground (5) or a base (5) form a rectangle or a square.

[0052] Each motor is powered by a cable (not shown). In this embodiment, the cables of the four powertrains are combined into a cable bundle.

[0053] Data transmission to the motors (1) is also achieved via cable in this embodiment. A computer system is used to generate instructions for each motor, based on simulation data and user actions. Various sensors can be connected to the computer system.

[0054] [Fig. 6] represents the optional implementation of a stabilizer bar (9) connecting two powertrains, in order to mitigate the stresses that may be exerted on a movement platform (P). The stabilizer bar is here attached between attachment points (8) located on the support frame (6).

[0055] [Fig. 3] represents the typical implementation of four omnidirectional drive units on a motion platform (P) made of a chassis of extruded aluminum profiles. It should be noted that the connection interface (7) here includes a perforation pattern corresponding to the standard generally used for this type of chassis, the grooves of which are vertically spaced 4 cm apart to facilitate the installation of fasteners.

[0056] [Fig. 7] represents the mounting of powertrains on a movement platform (P) consisting of at least a partial replica of a vehicle. Here, this vehicle replica consists of a tubular chassis, the connection interface (7) being adapted for optimal grip.

[0057] In other embodiments, alternative mechanical reduction means (2) may be considered such as: gears, a planetary type gearbox, etc.

[0058] It will also be possible to use alternative mechanical power transmission means (3) including for example belts and pulleys, chains, cardan-type joints, etc. in order to transmit the mechanical power of each motor to the corresponding mecanum wheel.

[0059] In another embodiment, omnidirectional wheels of the holonomic type may be used. Three drive units, each having a connecting interface, then make it possible to obtain the desired degrees of freedom; the control algorithm will be different from that used for the control of four mecanum wheels.

[0060] We may also consider embodiments where the movement platform (P) will consist solely of a seat.

[0061] A connection interface may also have a configuration to facilitate screwing fasteners into a movement platform (P) having a base made of a material such as wood.

[0062] Other possibilities for applications of the invention are contemplated, such as, by way of non-limiting examples: dynamic seats for cinema, use in parks, etc.

Claims

Demands

1. Powertrain comprising, - an engine (1), - a mechanical reduction means (2) functionally connected to said motor (1), - a mechanical power transmission means (3) having an input and an output, said input being functionally connected to said mechanical reduction means (2), - an omnidirectional wheel (4) functionally connected to said output of said mechanical power transmission means (3), said omnidirectional wheel (4) being in contact with the ground (5) or a base (5), - a support frame (6) rigidly connecting the non-moving parts of said motor (1), said mechanical reduction means (2) and said mechanical power transmission means (3), creating a complete link between said non-moving parts, said powertrain being characterized in that said powertrain is configured for use in motion simulation to move a user from a motion platform (P) relative to the ground (5) or relative to a base (5), whereby said powertrain further comprises a connection interface (7) configured for connection with a motion platform (P), said connection interface (7) being connected to said support frame (6) of said powertrain.

2. Powertrain comprising: - an engine (1) having an engine casing, - a gearbox (2) having a gearbox casing, said gearbox being functionally connected to said engine, said gearbox casing and said engine casing being fully connected, forming a rigid engine-gearbox assembly, - a drive shaft (3) having one of its ends functionally connected to said gearbox (2), - an omnidirectional wheel (4) functionally connected to said drive shaft (3), said omnidirectional wheel (4) being in contact with the ground (5) or a base (5), - at least one bearing housing (3R) having a mounting flange, said bearing housing(s) (3R) being functionally connected to said transmission shaft (3) by pivot joint, - a support frame (6) rigidly connecting said engine-gearbox assembly and said mounting flange(s) of said bearing housing(s) (3R), creating a complete connection between said support frame (6), said engine-gearbox assembly and said mounting flange(s) of said bearing housing(s) (3R), said powertrain being characterized in that said powertrain is configured for use in motion simulation to move a user from a motion platform (P) relative to the ground (5) or relative to a base (5), whereby said powertrain further comprises a connection interface (7) configured for connection with a motion platform (P),said connection interface (7) being connected to said support frame (6) of said powertrain.

3. Powertrain according to claim 2, wherein said connection interface (7) is configured to be connected to a movement platform (P) having a chassis made of extruded metal profiles, said extruded metal profiles having a plurality of grooves.

4. Powertrain according to claim 2, wherein said connection interface (7) is configured to be connected to a movement platform (P) having a chassis made of tubular metal elements.

5. Powertrain according to claim 2, wherein said connection interface (7) is configured to be connected to a motion platform (P) consisting of at least a partial replica of a vehicle.

6. Powertrain according to claim 2, wherein said connection interface (7) is configured to be connected to a movement platform (P) consisting of a seat.

7. Powertrain according to claim 2, wherein said connection interface (7) is removably connected to said support frame (6) of said powertrain.

8. Powertrain according to claim 2, wherein said connection interface (7) comprises several perforations arranged in a square or rectangular pattern, one of the center-to-center distances of said perforation pattern having a length of 4 cm, or a multiple of 4 P1T1

9. Cili. Powertrain according to claim 2, wherein said support frame (6) further comprises - an attachment point (8) for a stabilizer bar, - a stabilizer bar (9) functionally connected to said attachment point (8), said stabilizer bar (9) being configured to be connected to another powertrain.

10. Powertrain according to claim 2, wherein said connection interface (7) further comprises, - an attachment point (8) for a stabilizer bar, - a stabilizer bar (9) functionally connected to said attachment point (8), said stabilizer bar being configured to be connected to another powertrain.

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