Motion generator

Abstract

The present invention relates to a motion generator including an end effector for movement relative to a surface, the end effector being moved by at least six actuation mechanisms, each actuation mechanism including an elongated tension member connected at one end to the end effector so that the end effector is suspended above the surface by the tension member and connected at its other end to an associated rocker of the same actuation mechanism so that the rocker is pivotally mounted about an axis fixed relative to the surface and so that actuation of the rocker moves the associated tension member and end effector. The present invention also relates to motion systems and simulators including such motion generators, and methods of operation and manufacture.

Description

Technical Field

[0001] The present invention relates to the field of motion systems. In particular, although not exclusive, the present invention relates to motion generators, and motion systems including such motion generators, and methods of using motion generators and motion systems.

Background Art

[0002] A motion generator is a device that can apply force and / or moment, movement, and acceleration to a payload in one or more degrees of freedom directions. The payload can be, for example, a human experiencing a simulated experience in a motion simulator based on a motion generator. A motion generator is used in a motion system including a control system.

[0003] Motion systems are used in various applications, including motion simulation (e.g., flight simulators and driving simulators), robotics, 3D printing, vibration, and earthquake simulation. The most common type of motion system currently used in motion simulation is the Stewart platform (or "hexapod"). This is a type of parallel robot having six actuators (usually hydraulic rams), which are paired and attached to three configurations on the base plate of the platform and intersect at three attachment points on the top plate. A payload, such as a device or a human user, is usually placed on the top plate in the form of a cockpit, a driver area, or a model vehicle, and is moved in six degrees of freedom, where a freely suspended object can move, i.e., three linear motions x, y, z (lateral, longitudinal, vertical) and three rotational motions (pitch, roll, and yaw) are possible.

[0004] A motion simulator is a mechanism that includes a motion system capable of creating the effects or sensations as if an occupant is riding in a moving vehicle. Motion simulators are specifically used to train drivers and pilots in the form of driving simulators and flight simulators respectively. They are also used industrially in the manufacture, design, and testing of vehicles themselves. Specialized motion simulators used in driving and flight simulators usually synchronize a visual display provided, for example, by a projection system and associated screen and audio signals with the movement of the carriage (or chassis) occupied by the driver or pilot to provide a better sense of the effect of movement. Motion simulators are also used in leisure or game applications (such as arcade video driving games). The emergence of virtual reality (VR) head-mounted displays (HMDs) has made aspects of immersive simulation in current motion systems less expensive and can provide virtual reality utilization in active games where one or more players control a driving, riding, flying, or first-person game experience, as well as in leisure applications such as passive amusement parks or arcade driving, riding first-person, or flying rides.

[0005] The type of hexapod commonly used in motion simulations where humans are participants usually has a relatively low bandwidth up to about 20 Hz. That is, it can create oscillatory movements and vibrations with a certain amplitude, and the frequency is up to 20 times per second. Beyond that, as the frequency increases, the amplitude of the movement decreases. This is sufficient to reproduce the movement of most vehicle suspensions, but it does not transmit the frequency components related to vibrations from automobile engines, tire vibrations, road noise, and the sharp edges of the curbs on the racetrack. The low bandwidth also means that the signal is delayed, that is, the driver cannot respond very quickly.

[0006] Current motion systems, especially those for high-performance applications such as military and commercial flight guidance and training utilization, are typically very large, heavy, complex, and extremely expensive. Their complexity requires extensive programming and maintenance, further expanding the user's costs. Dedicated driving simulator motion systems have been developed by McLaren / MTS Williams / ABD, Ansible, etc., but these tend to be mechanically very complex and thus extremely expensive, featuring precisely machined custom components and, in many cases, expensive linear motors. These dedicated driving simulator motion systems are more responsive than hexapods when moving in one direction but are still limited in other directions. The use of ball screws in such systems is disadvantageous in that while they are excellent at establishing position, they impede force transmission and can only achieve a lower bandwidth, making the experience for human users unnatural.

[0007] The applicant's prior patent publications WO2020 / 007506 and EP3591641 form part of the technical background of the present invention.

[0008] An object of the present invention is to provide an improved motion generator, and an improved motion system and simulator incorporating such a motion generator. One object of the present invention is to provide a motion generator capable of moving an end effector in six degrees of freedom and having a low manufacturing cost. Another object of the present invention is to provide a motion generator suitable for leisure or gaming utilization.

Summary of the Invention

[0009] According to one aspect of the present invention, there is provided a motion generator as claimed in claim 1. The advantage of such a motion generator is that the manufacturing cost is low. A further advantage of such a motion generator is that it is relatively simple to manufacture, or is particularly compact, for example, and is thus suitable for applications in leisure or games. The motion generator of the present invention still has a relatively high bandwidth. The motion generator may be back-drivable.

[0010] Further features of the motion generator according to the present invention are apparent from claim 2 to 17 alone or in combination.

[0011] According to another aspect of the present invention, there is provided a motion system, which includes a motion generator according to the present invention and a control system.

[0012] Another aspect of the present invention provides a simulator including a motion generator according to the present invention or a motion system according to the present invention and environmental simulation means.

[0013] A further aspect of the present invention provides a motion simulator for games or leisure applications including a motion generator according to the present invention. Preferably, the motion generator includes an end effector with a weight of less than 200 kg, less than 100 kg, or less than 50 kg and a motion generator control system, as is common in game applications.

[0014] The present invention also provides a method of using a motion generator or a motion system, for example, as described in one of claims 21 to 23.

[0015] The present invention also provides a method of manufacturing a motion generator or a motion system, as described in claims 24 to 25.

[0016] Here, the motion generator, motion system, and driving simulator of the present invention, as well as their operations and manufacturing, will be described by way of example only with reference to the attached FIGS. 1 to 11.

Brief Explanation of the Drawings

[0017]

Figure 1

Figure 1A

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Figure 11

[0018] Motion generator The motion generator 10 according to the present invention is shown in FIG. 1. The motion generator 10 has a surface 12, for example, attached to the floor of a building where the motion generator is placed.

[0019] The motion generator 10 has an end effector in the form of a platform 14 for supporting a payload, here including a user 16. The platform 14 is here, for example, a replica of a racing car cockpit suitable for gaming or leisure use. The platform 14 is suspended from six elongate tension members T1 - 6 included in six actuating mechanisms (not fully shown). One end of each of the elongate tension members T1 - 6 in the actuating mechanism is connected to the platform 14, and the other end is respectively connected to the ends of the associated rockers R1 - 6 in the actuating mechanism. As shown in FIG. 1A, the rockers R1 - 6 are pivotally mounted on the surface 12 and are free to pivot or oscillate in a counterclockwise or clockwise direction under the control of an actuator (usually a motor (not shown)) about an axis A indicated by straight lines A1, A2, A3, A4, A5 or A6 as shown by the curved arrows. Examples of the actuator and the complete actuating mechanism will be described in detail below. In the embodiment shown, the rockers R1 - 6 are mounted on the surface 12. These rockers are preferably attached to or included in a frame that supports the motion generator.

[0020] How to use the motion generator The motion generator 10 can be operated, for example, as shown in FIG. 11, usually under the command of a control system, by operating the operating mechanism of the generator. As a result, the suspended end effector 14 is moved in six degrees of freedom by the rocking motion of the six tension members in the six operating mechanisms.

[0021] The motion generator 10 shown in FIG. 2 shows the end effector 14 in the yaw left state. In this state, the displacement state of the rocker is as follows.

[0022] [Table 1] FIG. 3 shows the motion generator with the end effector in the pre-surge state. In this state, the displacement state of the rocker is as follows.

[0023] [Table 2]

[0024] Although the above two conditions are described, it is preferable that the suspended end effector 14 can be moved to other states including right swing, up swing, down swing, surge back, and any combination of such states by the rocking motion of the six tension members in the six operating mechanisms.

[0025] Operating mechanism Figures 4 and 5 show one type of operating mechanism used in the motion generator of the present invention. The motion generator 10 shown in FIG. 4 includes six operating mechanisms as generally described in connection with FIGS. 1-3, and the same elements are numbered the same. One of the operating mechanisms is shown in detail in FIG. 5. The elements of the operating mechanism (e.g., X) are given the numbers of the operating mechanisms (i.e., X1, X2, X3, X4, X5, or X6) in the following description of the different types of operating mechanisms. The motion generator is provided with six such operating mechanisms. In this form of operating mechanism, as shown in detail in FIG. 5, the rocker R is associated with an electric motor M having a toothed capstan C (not shown). The elongated toothed belt B has one end connected to a spring S that maintains the tension of the belt. The other end of the toothed belt B is connected to an elongated tension member TM that successively suspends the end effector 14. The motion generator is provided with six such operating mechanisms. Under the command from the control system, the operation of the motor M causes the "free ends" (i.e., the non-pivotally attached ends) of the associated rockers R1-6 to be displaced clockwise or counterclockwise through the movement of the associated toothed belt B. Thereby, the tension member T connected to the rocker that causes the movement of the end effector moves, in connection with FIGS. 2 and 3, in response to the displacement of the effector by the rockers R1-6, for example, to the yaw or surge forward configuration described above.

[0026] Operating mechanism Figure 6 shows another type of operating mechanism used in the motion generator of the present invention. The motion generator 10 shown in Figure 4 is as generally described in connection with Figures 1-3 again, and the same elements are numbered the same. In this type of operating mechanism, a rocker R pivotally attached is associated with a motor RM connected to a shaft (not shown). The free end of the rocker R is successively connected to a tension member that suspends the end effector 14. By direct connection with the rocker, under the command from the control system, the operation of the motor RM causes the associated shaft to move, and the associated rockers R1-6 are displaced clockwise or counterclockwise.

[0027] Operating mechanism Figures 7 and 8 show further operating mechanisms used in the motion generator of the present invention. The motion generator 10 shown in Figure 7 is as generally described in connection with Figures 1-3 again, and the same elements are numbered the same. Figure 8 shows one operating mechanism in detail. In this form and the operating mechanism shown in detail in Figure 8, a rocker R pivotally attached to an axle A is associated with a motor M having a toothed capstan C (not shown) on a shaft. An elongated toothed belt TB has both ends connected to the rocker R at around the midpoint of the rocker and engages with the capstan C. Alternatively, the toothed belt TB is continuous and preferably fixed to the rocker R at one point. Other connection points are also envisioned. A connection point towards the free end of the rocker may be preferred. An idler pulley P is biased by a spring S to maintain the tension of the belt B. The free end of the rocker R is successively connected to an elongated tension member TM that suspends the end effector 14. Six such operating mechanisms are provided for the motion generator. When the electric motor M operates under the command from the control system, the movement of the associated toothed belt B causes the associated rockers R1-6 to be displaced clockwise or counterclockwise. Thereby, the tension member moves, for example, following the displacement of the effector by the rockers R1-6, causing the movement of the end effector 14 into the yaw or surge forward configurations described above in connection with Figures 2 and 3.

[0028] In the above, several different types of operating mechanisms have been described as examples. The motion generator according to the present invention can include six operating mechanisms of the same type, or, for example, the operating mechanisms of the type described above can be mixed. The motion generation according to the present invention may, perhaps for reasons of redundancy, include more than six such operating mechanisms.

[0029] Motion system The motion system of the present invention includes a motion generator according to the present invention and an associated motion generator control system. FIG. 11 shows a control system suitable for use in controlling the operation of a motion generator according to the present invention. The control system 701 shown in FIG. 11 may receive input from a user. In connection with FIG. 11, the motion generator of the motion system is referred to as 702, but the control system 701 can be utilized for other motion generators, motion systems, and motion simulators such as the generator 10 and the motion simulators 20, 30 described herein. The control system 701 includes a motion controller 704 that executes a computer program, preferably in a deterministic or real-time manner, and receives a motion demand input 705 from a demand generator such as a simulation environment 703 or a set point generator 706. The motion controller calculates the required position, acceleration, and / or force 707 to be generated by each actuator 709 in order to generate the required motion profile 705. The control system 701 also includes a servo drive 708 that provides a precisely controlled current 710 to drive the actuator 709. During operation, the motion controller transmits the required position or force 707 to each servo drive 708. The actuator 709 has a motion measuring device 711 such as an encoder that provides motion feedback 712 to the motion controller, optionally via the servo drive. The motion controller compares the required motion profile 705 with the measured one 712 and updates the actuator demand 707 accordingly. FIG. 11 also shows a control system with a simulation environment 703 that includes the physics of a simulated vehicle and a driving simulation in which its environment such as a racecourse or an urban road is calculated. In this embodiment, the control system 701 receives a motion demand from the simulation environment 703 that represents the movement of the virtual vehicle.The computer program determines the movement of the vehicle in the virtual world 714 and then applies a motion cuing algorithm 713 (MCA, also known as a washout filter) to convert the simulated vehicle movement into something that can be represented by the motion generator 701. These calculated movements are then provided to the control system as motion demands 705. The MCA 713 can be part of the simulation environment 703 or the control system 701, or separated into both. The simulation environment 703 can receive input signals 715 from a control device 716 such as a steering, throttle, or brake input, which are used by a human user, i.e., an operator such as a driver, passenger, or pilot, to control the virtual vehicle in the simulation environment. The operator can be a passenger in the motion generator 702. These inputs 715 can be returned to the simulation environment either via the control system or directly. The simulation environment can also generate an output for a visual display 717 for the driver, passenger, or other user or operator. The simulation environment may also require additional data 718 from the control system related to, for example, the position of the motion generator or the input signals of the control device.

[0030] Motion Simulator Motion simulators 20 and 30 according to the present invention are shown in FIGS. 9 and 10. The motion simulator 20 includes a motion system 21 (including a control system 20CS) according to the present invention (e.g., as described above) and at least one environment simulation means.

[0031] In the motion simulator 20 of FIG. 9, the environment simulation means includes a projection system 20PS and a screen 22. Separate environment simulation means in the form of an audio system may also be provided.

[0032] In the motion simulator 30 of FIG. 10, the environment simulation means is in the form of a virtual reality headset 32 worn by the user 16. FIG. 10 also shows user input devices, here joysticks 34, 35, that can be used to provide input to the associated motion generator control system 30CS.

[0033] Method of manufacturing a motion generator The method of manufacturing a motion generator according to the present invention can be compromised, providing an end effector and at least six actuating mechanisms, each actuating mechanism including an elongated tension member connected to the end effector at one of its ends, whereby the end effector is suspended above the surface by the tension member, and the other end is connected to an associated rocker of the same actuating mechanism, whereby the rocker is mounted so as to be pivotable about an axis fixed relative to the surface, and when the rocker operates, the associated tension member and the end effector move, and the method may further include connecting a control system to the motion generator to manufacture a motion simulator.

Claims

1. A motion generator including a platform for supporting a payload, wherein the platform is movable relative to a surface, wherein the platform is movable by at least six actuating mechanisms, each actuating mechanism having a first end and a second end, the first end being an elongated tension member connected to the platform, and a rocker associated with the elongated tension member, whereby the platform is suspended above the surface by the elongated tension member, the second end being connected to the rocker associated with the elongated tension member, whereby the rocker is pivotable about an axis fixed relative to the surface, the rocker having a non-pivotable attachment end displaceable by pivoting of the rocker about the axis, and when the rocker operates and the non-pivotable attachment end of the rocker is displaced, the elongated tension member associated with the rocker and the platform are moved, a motion generator.

2. The motion generator according to claim 1, wherein each elongated tension member is connected at a point along the length of the rocker associated with the elongated tension member.

3. The motion generator according to claim 2, wherein the point is directed towards the non-pivotable attachment end of the rocker.

4. The motion generator according to claim 3, wherein each rocker is pivotably attached to a rotary joint or bearing.

5. The motion generator according to any one of claims 1 to 4, wherein at least one actuating mechanism includes a motor drivably connected to the rocker.

6. The motion generator according to claim 5, wherein the motor is an electric motor, a torque motor or a geared motor.

7. The motion generator according to claim 6, wherein all of the actuating mechanisms include an electric motor, a torque motor, or a geared motor drivably connected to the rocker.

8. The motor of one actuating mechanism is connected to the rocker of the actuating mechanism by a shaft that is drivably connected to the rocker at the position of the shaft, whereby, in use, the rocker pivots by rotation of the shaft, the motion generator according to claim 7.

9. The motion generator according to claim 8, wherein the shaft is concentric with the axis about which the rocker pivots.

10. The motion generator according to any one of claims 1 to 7, wherein at least one actuating mechanism includes a belt connected to the rocker at a point along the length of the rocker, and the belt is maintained in a tensioned state.

11. The motion generator according to claim 10, wherein all of the actuating mechanisms include a belt connected to the rocker at a point along the length of the rocker, and the belt is maintained in a tensioned state.

12. The motion generator according to claim 11, wherein the point is directed towards the non-pivoting attachment end of the rocker.

13. The motion generator according to claim 12, wherein the belt is connected to the rocker at the end of the rocker.

14. The motion generator according to any one of claims 10 to 13, wherein the belt is actuated by a capstan or pulley actuated by a related motor or other drive device, and tension is maintained by a spring or other elastic member attached to the other end.

15. The motion generator according to any one of claims 1 to 7 or claims 10 to 13, wherein at least one actuating mechanism includes an elongated belt whose both ends are connected to the rocker and is actuated by a capstan or pulley or is actuated by a motor and tension is optionally maintained by an idler pulley connected to a spring or other elastic member.

16. The motion generator according to claim 15, wherein all of the actuating mechanisms include such an elongated belt, and the elongated belt is maintained in a tensioned state.

17. The motion generator according to any one of claims 1 to 16, wherein the surface is a floor or a support of the motion generator.

18. A motion system comprising the motion generator according to any one of claims 1 to 17 and a motion generator control system.

19. A motion simulator comprising the motion generator according to any one of claims 1 to 17 and at least one environment simulation means.

20. The motion system according to claim 18, A motion simulator comprising at least one environment simulation means.

21. A motion simulator for gaming or leisure use, comprising a motion generator according to any one of claims 1 to 17 and a motion generator control system, and including a platform having a weight of less than 200 kg, less than 100 kg or less than 50 kg.

22. A method of operating a motion generator according to any one of claims 1 to 17, or a motion simulator including the motion generator, the method comprising operating a part or a plurality of the actuating mechanisms to move the platform with up to six degrees of freedom.

23. The method according to claim 22, wherein the operation is performed by a motion generator control system connected to the motion generator or within the motion system.

24. The method according to claim 23, wherein the motion generator control system is operated by a user.

25. A method of manufacturing a motion generator, wherein the method comprises Providing a platform for supporting a payload and a component including at least six actuating mechanisms, each actuating mechanism having a first end and a second end, the first end being an elongate tension member connected to the platform, and a locker associated with the elongate tension member, whereby the platform is suspended above the surface by the elongate tension member, the second end being connected to the locker associated with the elongate tension member, whereby the locker is pivotable about an axis fixed relative to the surface, the locker having a non-pivotable attachment end displaceable by pivoting of the locker about the axis, and when the locker operates and the non-pivotable attachment end is displaced, the elongate tension member associated with the locker and the suspended platform are moved, assembling the foregoing components to manufacture a motion generator according to any one of claims 1 to 17, a method of manufacturing a motion generator.

26. A method of manufacturing a motion system, the method including manufacturing a motion generator according to claim 25 and connecting a control system to the motion generator.

27. The motion generator according to claim 1, wherein the position of the axis of the locker in each actuating mechanism is lower than the position of the platform.

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