Abstract
This invention relates to a three degree of freedom motion generator for moving a payload above the surface, the motion generator comprising a rotatable platform arranged for rotation on a circular guide above the surface, at least three linear guides extending ray-wise above the surface from a centre, each linear guide having a linear guide carriage moveable thereon, a peripheral guide carriage pivotally mounted on each linear guide carriage about the periphery of the rotatable platform, and a plurality of actuators, whereby at least one actuator may be operated to exert a force between a peripheral guide carriage on the circular guide and the rotatable platform. Other aspects include a motion system, and vehicle driving simulators including such a motion generator.
Claims
1. A motion generator for moving a payload in three degrees of freedom above the surface, the motion generator comprising a rotatable platform arranged for rotation on a circular guide above the surface, at least three linear guides extending ray-wise above the surface from a centre, each linear guide having a linear guide carriage moveable thereon, a peripheral guide carriage mounted for rotation on each linear guide carriage about the periphery of the rotatable platform, and a plurality of actuators, whereby at least one actuator may be operated to exert a force between a peripheral guide carriage and the rotatable platform to rotate the platform and in which the rotatable platform may also be translated above the surface by the operation of at least one actuator.
2. The motion generator according to claim 1, in which the rotatable platform may be simultaneously rotated and translated.
3. The motion generator according to claim 1, in which the linear guides are mounted on the surface.
4. The motion generator according to claim 1, in which the circular guide is on the rotatable platform.
5. The motion generator according to claim 1, in which the linear guide carriages can be driven to move on the linear guides by actuators.
6. The motion generator according to claim 1, in which either: at least one of the actuators comprises a linear motor; or all the actuators comprise a linear motor.
7. (canceled)
8. The motion generator according to claim 1, in which one of the peripheral guide carriages and the rotatable platform includes at least one linear motor coil which interacts with a corresponding linear motor magnet way on the other of the peripheral guide carriages and the rotatable platform to rotate the platform.
9. The motion generator according to claim 1, in which: the peripheral guide carriage comprises the linear motor coil(s) and the rotatable platform comprises the corresponding linear motor magnet way, and one or more of: the, or each, linear motor magnet way is curved, or the, or each, linear motor coil is curved.
10. (canceled)
11. (canceled)
12. The motion generator according to claim 1, in which: at least one actuator comprises a belt drive, and one or more of: the said at least one actuator is operable to rotate the rotatable platform, or the belt-drive is an omega belt drive.
13. (canceled)
14. (canceled)
15. The motion generator according to claim 1, in which at least one actuator comprises a gear which can drive a corresponding toothed rim on the platform to rotate the platform.
16. The motion generator according to claim 1, in which movement of two adjacent linear guide carriages along their respective linear guides towards the centre moves the rotatable platform above the surface away from the centre.
17. The motion generator according to claim 1, in which movement of two adjacent linear guide carriages along their respective linear guides away from the centre moves the rotatable platform above the surface towards the centre.
18. The motion generator according to claim 1, in which the rotatable platform can rotate by up to, or more than, 360 degrees.
19. The motion generator according to claim 1, in which the payload is a vehicle chassis or cockpit or model thereof.
20. A motion system comprising: a motion generator according to claim 1, and a control system arranged to control operation of the motion generator.
21. A combination comprising: a first motion generator according to claim 1 as a primary motion generator/motion system, and a secondary motion generator on the rotatable platform of the first motion generator.
22. A combination according to claim 21, in in which the secondary motion generator is a 3, 4, 5 or 6 degrees of freedom motion generator.
23. A vehicle driving simulator comprising: a motion generator according to claim 1, and at least one environment simulation means selected from visual projection or display means, and audio means.
24. A vehicle driving simulator according to claim 23, in which the projection or display means extends completely around the rotatable platform.
25. A vehicle driving simulator according to claim 23, in which the projection and or display means is mounted about the rotatable platform, preferably for movement linked to the platform.
26. A method of producing a motion generator according to claim 1, the method comprising: providing a rotatable platform arranged for rotation on a circular guide above the surface, arranging at least three linear guides to extend ray-wise above the surface from a common point, providing each linear guide with a linear guide carriage moveable thereon, a peripheral guide carriage pivotally mounted on each linear guide carriage about the periphery of the platform, and a plurality of actuators, whereby, in use, each actuator may be operated to exert a force between a peripheral guide carriage on the circular guide and the rotatable platform.
Description
BRIEF DESCRIPTION OF THE FIGURES
[0019] Motion generators, motion systems and vehicle driving simulators in accordance with the invention will now be described, by way of example only, with reference to the accompanying drawings, FIGS. 1 to 24, in which:
[0020] FIG. 1 is a perspective view from above on one side of a motion generator in accordance with the invention;
[0021] FIG. 2 is a detail view showing a portion of the motion generator of FIG. 1;
[0022] FIG. 3 is a vertical cross-sectional view of another portion of the motion generator of FIG. 1;
[0023] FIG. 4 is a schematic perspective view of the motion generator in accordance with the invention in a nominal or normal condition;
[0024] FIG. 5 is a schematic perspective view of the motion generator of FIG. 4 in a surge rearward configuration condition;
[0025] FIG. 6 is a schematic perspective view of the motion generator of FIG. 4 in a surge forward condition;
[0026] FIG. 7 is a schematic perspective view of the motion generator of FIG. 4 in a sway rightward condition;
[0027] FIG. 8 is a schematic perspective view of the motion generator of FIG. 4 in a sway leftward condition;
[0028] FIG. 9 is a schematic perspective view of the motion generator of FIG. 4 in a yaw anticlockwise (as viewed from above) condition;
[0029] FIG. 10 is a schematic perspective view from above of the motion generator of FIG. 4 in a yaw clockwise condition;
[0030] FIG. 11 is a schematic perspective view of the motion generator of FIG. 4 in an extreme yaw condition;
[0031] FIG. 12 is a schematic perspective view of the motion generator of FIG. 4 in a combined surge rearward and sway rightward condition;
[0032] FIG. 13 is a schematic perspective view of the motion generator of FIG. 4 in a combined surge rearward and yaw anticlockwise condition;
[0033] FIG. 14 is a schematic perspective view of a motion generator in accordance with a different embodiment of the invention;
[0034] FIG. 15 is a detailed view of a detailed view of a portion of the motion generator of FIG. 14;
[0035] FIG. 16 is a plan view of the motion generator of FIG. 14 in accordance with the invention;
[0036] FIG. 17 is a perspective view from above and one side of another motion generator in accordance with the invention;
[0037] FIG. 18 is a perspective view from below and one side of the motion generator of FIG. 17;
[0038] FIG. 19 is a plan view of the motion generator of FIG. 17 in a surge forward condition;
[0039] FIG. 20 is a plan view of the motion generator of FIG. 17 in a sway right condition;
[0040] FIG. 21 is a plan view of the motion generator of FIG. 17 with the chassis in a sway right, and yaw right condition;
[0041] FIG. 22 is a plan view of the motion generator of FIG. 17 with the chassis in a sway left, and extreme yaw condition;
[0042] FIG. 23 is a schematic view of a co system for use with a motion generator in accordance with the invention; and
[0043] FIG. 24 is a schematic view of a vehicle driving simulator in accordance with the invention.
DETAILED DESCRIPTION OF VARIOUS EMBODIMENTS
[0044] Motion Generator
[0045] FIGS. 1-3 show a motion generator 10 in accordance with the invention. The motion generator 10 comprises a rotatable circular platform 12 which is arranged to rotate above a surface 13 (identified in FIG. 3). The motion generator 10 further comprises three actuator assemblies, 2, and 3, which extend ray-wise from a centre. The actuator assemblies 1, 2, 3, each comprises a linear guide actuator in the form of a linear motor 101, 201, and 301 respectively. Furthermore, the actuator assemblies 1, 2, 3 each comprise a linear guide carriage 102, 202, and 302 which are driven by the linear motor 101, 201, and 301 respectively on associated linear guides 103, 203, and 303 which extend ray-wise from the centre. It will be appreciated by the skilled addressee that in the context of the present invention, the “centre” does not refer to an exact central point, and the linear guides may be offset from a central point. Therefore, the term “centre” is used in a more general sense than for example the term “point”. A peripheral guide carriage (104, 204, and 304) is mounted on the associated one of the linear guide carriages 102, 202, and 302. The peripheral guide carriages 104, 204, and 304 are pivotally mounted on the respective linear guide carriages 102, 202; and 302 and support the periphery of the rotatable platform 12. As shown in more detail in FIG. 3, peripheral guide carriage 103 supports the periphery of rotatable platform 12. Guide rails 14 and 16 are disposed around the periphery of upper and lower surfaces of the rotatable platform 12. The circular guide rails 14, 16 are arranged to travel within peripheral guide carriage trucks 18, 20 respectively. As shown in FIG. 3, the peripheral guide carriage 103 is mounted for pivotal movement by spherical beating 22 on the linear carriage truck 102 which is, in turn, mounted for sliding movement on the linear guide 103 and driven by linear motor 101. The peripheral guide carriage also supports a curved circular linear coil 24. A correspondingly shaped circular linear motor magnet way 26 is arranged around the periphery of the rotatable platform 12.
[0046] In use under the control of a control system (for example as described above in relation to FIG. 23) the linear motor including coil 24 and magnet way 26 imparts a tangential force on the rotatable platform 12 in a chosen direction of rotation. Whilst only peripheral guide carriage 104 has been described in detail above, the other actuator assemblies 2, and 3; linear motors 201, and 301; linear guide carriages 202, 302; and peripheral guide carriages 204, 304 are similarly arranged so that the linear motors provided by peripheral guide carriages 104, 204; and 304 together can be operated together to rotate the platform 12 into different rotational positions about a vertical axis with great precision. The platform 12 may rotate about the vertical axis through up to or more than 360°. In order to facilitate rotation through more than 360°; special electrical connections may be used. For example, one or more slip rings might be used to maintain electrical continuity between the actuators and a control system. Additionally, or alternatively, the linear guide carriages 102, 202, and 302 can be moved by the corresponding linear motors 101, 201, and 301 along the corresponding linear guides 103, 203, and 303, to translate the rotatable platform 12 in to different horizontal positions along a plane parallel with the surface 13. The motion generator 10 described above demonstrates good levels of excursion which is useful; for example; in vehicle driving simulation. For example, platform 12 may move 2 metres in any horizontal direction from the centre.
[0047] The movement of the linear guide carriages and peripheral guide carriages of the motion generator in accordance with the invention are described in more detail below.
[0048] Motion Generator
[0049] A motion generator 400 in accordance with another embodiment of the invention is shown in FIGS. 14,15, and 16. In this embodiment, the curved linear motors of the FIG. 1-13 embodiment are replaced by an omega belt drives which engage a peripheral toothed belt arranged around a rotatable platform. Suitable omega belt drives are produced, for example, by Bosch Rexroth AG, and may be more economical than linear motors. In more detail, motion generator 400 comprises a rotatable platform 412 which supports a chassis 430. The rotatable platform 412 is supported for rotation about a vertical axis above surface 413 by peripheral guide carriages 41 PGC, 42PGG, 43PGC and 44PGC on associated linear guide carriages 41 LGC, 42LGC, 43LGC and 44LGC which are arranged to move along associated linear guide rails 41 LG, 42LG, 43LG and 44LG driven by linear motors (not shown). The peripheral guide carriages 41 PGC, 42PGG, 43PGC and 44PGC support omega belt drives 41 BD, 42BD, 43BD, and 44BD which engage a toothed belt 414 disposed around the periphery of the rotatable platform 412 and can be driven to rotate the platform 412 in either direction. The omega belt drives 41 BD, 42BD, 43BD, and 44BD and toothed belt 414 are shown in more detail in FIG. 15. The actuators (the omega belt drives, and the linear motors) are operated under the control of a control system (for example as described in relation to FIG. 23). The rotatable platform 412 can be rotated with great precision through many orientations including extreme yaw angles (i.e. 360° or greater). Furthermore, the rotatable platform 412 can be displaced horizontally (translated) above surface 413 by coordinated operation of adjacent linear guide carriages 41 LGC, 42LGC, 43LGC, and 44LGC to push the rotatable platform. For example, FIG. 16 shows the motion generator 400 in a combined sway left and 100-degree left yaw condition. This embodiment also features good excursion levels for a motion generator of its size. Specifically, the moving part (i.e. platform 412) may have a diameter of 3 metres, but it may move by in excess of 1 metre in any horizontal direction. It will be appreciated that the peripheral toothed belt 414 may be replaced by a flat belt which is driven by suitable drives.
[0050] Motion Generator
[0051] In a further embodiment of a motion generator in accordance with the invention, the omega belt drive actuators described in relation to the motion generator described in FIG. 14-17 are replaced by rotary actuators, each rotary actuator driving a gear which engages a toothed rim arranged around the periphery of the platform. This embodiment has similar advantages to the FIG. 14-17 embodiment.
[0052] Combination of Motion Generators
[0053] A combination comprising a primary motion generator 600 (which is a motion generator in accordance with the invention) in series with a further motion generator, to form a combination is shown in FIGS. 17-22. The motion generator 600, which is mounted on surface 60, comprises a rotatable platform 602 has four actuator assemblies 604, 606, 608, and 610 which each extend outwardly at right angles from an adjacent actuator assembly from a centre 6. Each actuator assembly comprises a linear guide 604LG, 606LG, 608LG, and 610LG respectively; a driveable linear guide carriage 604GC, 606GC, 608GC, and 610GC respectively arranged for movement along the associated linear guide; and a linear motor 604LM, 606LM, 608LM, and 610LM respectively. The platform is arranged for rotation about a vertical axis being supported by the rollers on the upper surface of linear motors 604LM, 606LM, 608LM, and 610LM which engage with rails 612, 614 of a circular track at the base of the platform. As with other motion generators the invention, the platform 602 may rotate about the vertical axis through more than 360°. For example, one or more slip rings might be used to maintain electrical continuity between the actuators and a control system. A circular magnet way 615 is also arranged at the base of the platform 602 between rails 612,614. A chassis 616 is supported above the platform 602 on straits 618,619, 620 (obscured) 621, 622, and 623. The struts are provided by another motion generator 630 (which is not shown or described in detail) which is mounted on the platform 602 of motion generator 600, as a secondary motion generator) and which provides 6 degrees of freedom movement for the chassis 616.
[0054] In use, the platform 602 is rotated with great precision about a vertical axis through operation of some or all of the linear motors 604LM, 606LM, 608LM, and 61 OLM respectively under the control of a control system (for example as described in relation to FIG. 23) interacting with the magnet way 615. The platform can also be moved in X and Y directions, again with great precision, from the neutral or nominal condition shown in FIG. 17 or 18 by movement of the linear guide carriages 604GC, 606GC, 608GC, and 610GC along their respective linear guides. For example, FIG. 19 shows the platform 602 in a surge forward condition. FIG. 20 shows the platform 602 in a sway right condition.
[0055] The motion generator 600 described above demonstrates good levels of excursion which is useful, for example, in vehicle driving simulation. For example, platform 602 may move 2 metres in any, horizontal direction from the centre. Furthermore, the secondary motion platform provides additional motion. It will be noted that only a limited number of conditions is described above. It will be appreciated by the skilled addressee that the primary 600 and secondary motion generators 630 may be operated independently or in combination to move chassis 616 into many more conditions such as those described above and below and including, but not exclusively surge rearward, sway right, heave down, roll left side down, pitch nose up and yaw nose right. For example, FIG. 21 shows the platform 602 in a combined surge right and yaw right condition. Furthermore, it will also be appreciated by the skilled addressee that the primary 600 and secondary 630 motion generators may be operated to move the chassis 616 into multiple combinations of such conditions.
[0056] Control System
[0057] FIG. 2.3 shows a control system 701 for use in controlling operation of a motion generator in accordance with the invention. In relation to FIG. 23, the motion generator is referred to as 702, but the control system 701 is applicable to the other motion generators, motion systems, and motion simulators described herein. The control system 701 comprises a motion controller 704 which executes a computer program, preferably in a deterministic or real time manner, and which takes motion demand inputs 705 from a demand generator such as a simulation environment 703 or a set point generator 706. The motion controller computes the positions, accelerations and/or forces 707 required to be produced at each actuator 709 to in order to generate the demanded motion profile 705. The control system 701 also comprises servo drives 708 which provide precisely controlled electrical currents 710 to drive the actuators 709. In operation, the motion controller sends to each servo drive 708 a demanded position or force 707. The actuator 709 has a motion measurement device 711, such as an encoder, which provides motion feedback 712 to the motion controller, optionally via the servo drive. The motion controller compares the demanded motion profile 705 to the one measured 712 and updates the actuator demand 707 accordingly. FIG. 23 also shows the control system with a simulation environment 703, such as a driving simulation in which the physics of a simulated vehicle and its environment, such as a racetrack or city roads, are computed. In this embodiment the control system 701 receives motion demands from the simulation environment 703, which represent the motion of a virtual vehicle. The computer program determines the motion of the vehicle in a virtual world 714, then applies a motion cueing algorithm 713 {MCA, also known as washout filters) to transform the simulated vehicle motions into those that can be represented by the motion generator. These calculated motions are then provided to the control system as motion demands 705. The MCA 713 could be part of the simulation environment 703 or the control system 701 or separate to both. The simulation environment 703 may receive inputs signals 715 from control devices 718 such as steering, throttle or brake inputs, which an operator, i.e. a human user such as a driver, passenger or pilot uses to control the virtual vehicle in the simulation environment. The operator would likely, be a passenger on the motion generator 702. These inputs 715 may be passed back to the simulation environment via the control system or directly. The simulation environment is also likely to produce an output on 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, such as relating to the position of the motion generator, or control device inputs signals.
[0058] Method of Operating a Motion Generator/Motion System
[0059] The motion generators described above can be combined with a control system (for example, as described in relation to FIG. 23) to produce a motion system. The motion generators can be controlled by the control system to move into the conditions shown by way of example in FIGS. 4-11. In the motion system arrangement shown in FIGS. 4 to 11, a motor racing vehicle chassis 30 is mounted on the rotatable platform 12 of a motion generator 10 in accordance with the invention The motion generator may be any motion generator in accordance with the invention, or all or part of a combination of motion generators in accordance with the invention.
[0060] Nominal
[0061] In FIG. 4, the motion generator platform 12 is shown in a nominal or neutral condition with the chassis pointing in direction X. The movement of each linear guide carriage 102, 202, 302 and associated peripheral guide carriage, 104, 204, 304, and the orientation of the rotatable platform 12 in this condition is as follows:
TABLE-US-00001 Peripheral guide carriage with Linear guide respect to Platform Actuator carriage (top down view) Platform 1 102- Neutral 104 - Neutral Neutral 2 202 - Neutral 204 - Neutral Neutral 3 302 - Neutral 304 - Neutral Neutral
[0062] Surge Rearward
[0063] In FIG. 5, the motion generator platform is shown in a surge rearward condition. The movement of each linear guide carriage 102, 202, 302 and associated peripheral guide carriage, 104, 204, 304, and the orientation of the rotatable platform 12 in this condition is as follows:
TABLE-US-00002 Peripheral guide carriage with Linear guide respect to Platform Actuator carriage (top down view) Platform 1 102- Outward 104 - clockwise Neutral 2 202 - Outward 204 - Anticlockwise Neutral 3 302 - Inward 304 - Neutral Neutral
[0064] Surge Forward
[0065] In FIG. 6, the motion generator platform is shown in a surge forward condition. The movement of each linear guide carriage 102, 202, 302 and associated peripheral guide carriage, 104, 204, 304, and the orientation of the rotatable platform 12 in this condition is as follows:
TABLE-US-00003 Peripheral guide carriage with Linear guide respect to Platform Actuator carriage (top down view) Platform 1 102- Inward 104 - Anticlockwise Neutral 2 202 - Inward 204 - Anticlockwise Neutral 3 302 - Outward 304 - Neutral Neutral
[0066] Sway Rightward
[0067] In FIG. 7, the motion generator platform is shown in a sway rightward condition. The movement of each linear guide carriage 102, 202, 302 and associated peripheral guide carriage, 104, 204, 304, and the orientation of the rotatable platform 12 in this condition is as follows:
TABLE-US-00004 Peripheral guide carriage with Linear guide respect to Platform Actuator carriage (top down view) Platform 1 102- Inward 104 -clockwise Neutral 2 202 - Outward 204 -clockwise Neutral 3 302 - Inward 304 - Anticlockwise Neutral
[0068] Sway Leftward
[0069] In FIG. 8, the motion generator platform is shown in a sway leftward condition. The movement of each linear guide carriage 102, 202, 302 and associated peripheral guide carriage, 104, 204, 304, and the orientation of the rotatable platform 12 in this condition is as follows:
TABLE-US-00005 Peripheral guide carriage with Linear guide respect to Platform Actuator carriage (top down view) Wheel 1 102- Outward 104 -Anticlockwise Neutral 2 202 - Inward 204 -Anticlockwise Neutral 3 302 - Inward 304 - clockwise Neutral
[0070] Yaw Anticlockwise
[0071] In FIG. 9, the motion generator platform is shown in a yaw anticlockwise (or to the left—either as viewed from above) condition. The movement of each linear guide carriage 102, 202, 302 and associated peripheral guide carriage, 104, 204, 304, and the orientation of the rotatable platform 12 in this condition is as follows:
TABLE-US-00006 Peripheral guide carriage with Platform Linear guide respect to Platform (as viewed Actuator carriage (top down view) from above) 1 102- Neutral 104 -Neutral Anticlockwise 2 202 - Neutral 204 -Neutral Anticlockwise 3 302 - Neutral 304 - Neutral Anticlockwise
[0072] Yaw Clockwise
[0073] In FIG. 10, the motion generator platform is shown in a yaw clockwise (or to the right—either as viewed from above) condition. The movement of each linear guide carriage 102, 202, 302 and associated peripheral guide carriage, 104, 204, 304, and the orientation of the rotatable platform 12 in this condition is as follows:
TABLE-US-00007 Peripheral guide carriage with Platform Linear guide respect to Platform (as viewed Actuator carriage (top down view) from above) 1 102- Neutral 104 -Neutral Clockwise 2 202 - Neutral 204 -Neutral Clockwise 3 302 - Neutral 304 - Neutral Clockwise
[0074] Extreme Yaw
[0075] In FIG. 11, the motion generator platform 12 is shown in a more extreme yaw clockwise or anticlockwise (as viewed from above) condition compared with the conditions shown in FIG. 9 or 10. As noted above the motion generator platform 12 of motion can be rotated through more than 360 degrees of rotation to move the payload of the motion generator—the chassis 30—into different orientations. The precise control of the rotation of the platform, the high levels of yaw for the payload, and its displacement in X and Y directions are advantageous features of the invention.
[0076] Vehicle Driving Simulator
[0077] A vehicle driving simulator 50 in accordance with the invention is shown in FIG. 24. The driving simulator 50 comprises a motion system 52 including a motion generator 53 in accordance with the invention (for example, as described above in relation to FIGS. 1 to 11, or in relation to FIGS. 17 to 22) which is mounted on a surface 54 in front of a projection system 56. The motion generator 53 is under the control of a control system 57. Images of a driving environment can be displayed to a user in chassis 58. An audio system 59 provides sound to the user replicating the sounds of a driving environment. Wrap around projection systems extending for 360 degrees around the periphery of the motion system 52 are also contemplated for a more immersive experience taking advantage of the extreme yaw performance of the motion system 52 of the invention resulting from the design of the motion generator 53. The projection and or display means may be mounted about the rotatable platform, preferably for movement linked to the platform. The motion generator 53 of the driving simulator 50 is operated under the command of a control system 57, generally as described above. It will be appreciated by the skilled addressee that the motion system 52 used in the vehicle driving simulator 50 is especially compact in the vertical direction. This better replicates the height of a vehicle being simulated, in comparison with other motion systems requiring ramps/bridges for a user to enter/exit the driving simulator. A user may enter the simulator through a building surface aperture between two of the linear guides.
[0078] Method of Producing a Motion Generator
[0079] Motion generators, motion systems, and vehicle driving simulators in accordance with the invention can be produced by conventional methods of construction and manufacture. Frequently off-the-shelf components may be used in their production.
[0080] Whilst the invention has been described in particular in relation to the use of motion generators in vehicle motion simulation applications, the skilled addressee will appreciate that the motion generators and motion systems of the invention will find other applications such as flying vehicle simulation and in particular simulating rotorcraft. The skilled addressee will also appreciate that numerous modifications and alterations can be made to the above embodiments, which are given by way of example only, without departing from the scope or spirit of the invention.
