GB2607124A

GB2607124A - Pneumatic actuator for shock absorbing suspension retraction

Info

Publication number: GB2607124A
Application number: GB2115886.0A
Authority: GB
Inventors: Richard Barwick Stephen; Robert Walter Humphreys Owen
Original assignee: Prodrive Advanced Technologies Ltd
Current assignee: Prodrive Advanced Technologies Ltd
Priority date: 2021-05-28
Filing date: 2021-11-04
Publication date: 2022-11-30
Anticipated expiration: 2041-11-04
Also published as: GB2607129A; GB2607125B; GB2607127A; GB2607126B; GB2607127B; GB2607125A; GB2607129B; GB2607126A; GB2607128A; GB2607128B; GB2607124B

Abstract

A suspension system for a wheeled vehicle is provided. The suspension system utilises one or more suspension modules. Each module comprises a pair of parallel control arms 10, 20 which are coupled at one end to the body of the vehicle and at the other end to a raft 90; a dampener 30 coupled to at least one of the control arms 10, 20; a pair of spring actuators (120, 130, Figure 3); one or more sensors for sensing one or more vehicle parameters; and a controller configured to control the suspension modules in response to signals from the sensors. A corresponding method of using such suspension modules is also disclosed.

Description

Pneumatic actuator for shock absorbing suspension retraction

Background

Vehicles, including wheeled vehicles, are typically suspended to absorb shock encountered while traversing uneven terrain. Wheeled vehicles usually include one suspension assembly per wheel so that each wheel may absorb shock independently. In many cases each such suspension assembly comprises both a spring portion and a damping portion. The spring portion may consist of a mechanical spring, such as a wound helical spring, or it may comprise a pressurized volume of gas. Gas is often used because it is light weight. Unlike typical simple mechanical springs, gas springs have non-linear spring rates. Compound mechanical springs may also have non-linear rates. A single gas spring has a spring rate that becomes highly exponential at compression ratios greater than about sixty percent. As a practical matter that can mean that a shock absorber including a gas spring can becomes very stiff just past the middle of its compressive stroke. Such excess stiffness over an extended length of the stroke is often undesirable (e.g., harsh riding vehicle).

In performing the dampening function, the damping mechanism of a shock absorber also creates resistance of the shock absorber to movement (e.g., compression and/or rebound). Unlike the spring which resists based on compressive displacement, fluid dampers usually have resistance to movement that varies with displacement rate (i.e., velocity). That may be disadvantageous because low velocity (i.e., low frequency) high amplitude shocks may compress the spring while the damper offers little resistance. In such cases the shock absorber may compress beyond a desired point because the damper did not contribute to shock compression resistance.

What is needed is a shock absorber dampener that offers resistance to movement as a function of axial displacement. What is needed is a suspension dampener that is relatively compliant at low axial displacement and progressively more resistant to movement at higher displacements. What is needed is a suspension (e.g., shock absorber, fork) having a gas spring with good low displacement resistance and more compliance at greater compression ratios. What is needed is a shock absorber having a gas spring and a dampener that can be tuned together to yield optimized shock absorber force/travel/velocity characteristics.

EP3114019A1 discloses a terrain-tracking or vehicle suspension system.

Summary

The present invention in its various aspects is as set out in the appended claims.

Disclosed is a suspension system for a wheeled vehicle. Specifically, a suspension system which utilises suspension modules to have wheels that are both hight adjustable and retractable, using a plurality of actuators coupled to the suspension module. Said actuators coupled to one of a hydraulic, pneumatic or electronic system to actuate the actuators. The actuators are preferably spring actuators which will allow the actuators to provide compliance to the suspension which will allow the suspension to remove in a manner to deflect impacts, reducing the effects of such impacts on the vehicle.

The system further comprising sensors to allow the wheels to adjust automatically to adapt to the conditions of the surface the vehicle is travelling on, such as responding to slopes, raised areas, breaks or ditches in the path surface. The system can also use the sensor information to identify obstacles in the vehicles path such as debris. And after identifying such obstacles the system will actuate the suspension modules to automatically avoid obstacles, or if it cannot be avoided the system with adjust the position of the module so as to reduce the impact when the obstacle is hit.

More specifically, the disclosed suspension system will comprise a plurality suspension module. Each module comprising a pair of parallel control arms rotatably coupled to a wheel hub, via a knuckle and pintle. The knuckle and pintle allow the control arms to pivot vertically and horizontally relative to the wheel hub, providing the ability to change the suspension profile, and the ability to retract the wheel hub, respectively. Each module than uses a pair of actuators to move the control arms, in particular first actuator controls vertical movements, while the second controls horizontal movements. The module will also comprise a dampener to provide shock absorption to the module. In the preferred embodiment of the invention the module comprises a dampener unit that act as the first actuator. In this case the dampener in in the form of a resilient member, such as an air spring, which can provide shock absorption while also expanding and contracting to actuate the control arms. Additionally, the second actuator can also comprise an air spring to again provide improved shock absorption.

The dampener unit and second actuator can be controlled using a hydraulic, pneumatic or electrical system. Of these options a pneumatic or electronic system is preferable over the hydraulic system, as the hydraulic system will require a reservoir within the vehicle, adding additional, unnecessary weight. These systems provide the benefit that the resilient members in the dampener and actuator, herein referred to as a spring, may have multiple set points. This is achieved by changing the spring constant of the air-spring to provide a certain amount of compliance/dampening in the actuators regardless of their current length. Allowing the system to provide improved shock absorption regardless of whether the actuators are expanded or contracted. The system can use the data received from the previously mentioned sensors to either predict or react to impacts, for example if the system is traveling over rough terrain the actuators can be adjusted to provide more compliance to improve shock absorption. The improved compliance will also allow the system to move faster over rough terrain without risk of increased damage.

In the preferred embodiment the suspension's control arms are designed so that the upper control arm has an aperture in the centre so that the dampener can pass through the aperture and connect directly to the lower control arms, between the ends of the lower control arm. By doing the weight of the dampener is more evenly distributed over the suspension. Additionally, this geometry reduces the force needed to actuate the dampener and the control arms.

In all embodiments, the purpose of the invention is to have an adaptable suspension system, that is utilising the received data, and/or user inputs, to adjust the suspension based on the terrain the vehicle is one. The suspension utilising actuators, comprising resilient members, to not only actuate the suspension system, but to also provide different amounts of compliance so as to provide improve comfort by deflecting impacts to the suspension. The actuators utilising hydraulic, pneumatic or electronic systems to adjust the compliance to multiple set points, independent of the actuators length.

The system may also comprise wheel hubs with onboard motors. These motors may be electrical or hydraulic. The system can adjust the speed of the wheel motors automatically to assist the adjustable suspension to further reduce the effects of impacts on the vehicle. For example, by reducing and/or limiting speed when traveling over rough terrain, and adjust the speed of the wheel while traveling over an obstacle to reduce impact or help maintain steering.

Figures Figure 1: depicts examples of the types of roads surfaces the suspension system would need to be able to adapt to.

Figure 1A: depicts the profiles of the road surfaces depicted in Figure 1.

Figure 2: depicts the pieces required to build the preferred embodiment of the suspension module.

Figure 3: depicts examples of control arms and actuators that can be used in embodiments of the invention.

Figure 4: depicts the control arms and dampener used in the preferred embodiment of the invention, wherein the dampener is acting as the first actuator, and with free standing using stays to support the dampener.

Figure 5: depicts a complete pair of suspension modules, of the preferred embodiment, as they would appear on a vehicle Figure 6: depicts the parts of the preferred embodiment that are used in the height adjusting 15 mechanism.

Figure 7: depicts the mechanism used to adjust the height of the suspension module Figure 8: depicts an example vehicle using the mechanism of figure 7, to adjust the profile of the vehicle.

Figure 9: depicts a vehicle adjusting a single wheel using the mechanism from figure 7, to match the profile of the road surface.

Figure 10: depicts an example vehicle adjusting all the wheels on one side of the vehicle, using the mechanism from Figure 7.

Figure 11: depicts the mechanism used to retract the suspension module.

Figure 12: depicts a complete pair of suspension modules, of the preferred embodiment, with the wheels both (i) expanded and 00 retracted.

Figure 13: depicts a complete set of suspension modules retracting (i) two wheels, (ii) all wheels.

Figure 14: depicts an example vehicle using the wheel retraction mechanism from figure 11.

Figure 15: depict example suspension systems with different numbers of suspension 30 modules.

Figure 16: depicts a suspension module according to the invention, coupled to a mounting support frame, which can then be mounted to a vehicle.

Figure 17: depicts how a pair of suspension modules can be mounted to a vehicle using the support frame from figure 16.

Summary of Parts

In this application, the detail description defines several embodiments for an adjustable suspension module suitable for a wheeled vehicle. Below is a list detailing the common parts and components used to form these different embodiments: Wheel hub 70: a wheel hub comprising at least an outboard side configured to be coupled to a wheel 71, and an inboard side configured to be coupled to the rest of the suspension module by means of a knuckle 80, as described below. The wheel hub 70 containing the means to rotate the wheel 71 around the wheel's rotational axis in the desired direction of travel. The means of rotation may be driven by an external motor, either contained within the vehicle or within the suspension module, these external motors may be in the form of a centralized motor connected to all the vehicles wheel hubs, or a plurality of motors, wherein each of the plurality of motors drives an individual wheel, a pair of wheels or a select group of wheels. However, it is preferable for the wheel hub 70 to be driven by an internal motor contained within the wheel hub itself For the use of an internal motor would allow a greater level of control over each individual suspension module, allowing each wheel to be driven at different speeds, possible also in different directions, to improve the vehicles stability when traversing difficult surfaces, and to allow the suspension module to more easily correct the vehicles steering by means of changing the speed of individual wheels. Further the use of smaller internal motors will help reduce the vehicle's overall weight and more evenly distribute the vehicle's weight between the plurality of wheels attached to the vehicle, this can also help to improve the vehicles steering. Note that regardless of the position of the motor, the wheel hub 70 may utilize an electric, pneumatic or hydraulic motor for drive the wheel, of these options the electric motor would be the most preferable, as it will require fewer parts for easier maintenance, and does not require a fluid reservoir that would increase the weight of the vehicle.

Knuckle 80: the knuckle comprises a plate that is couples to the inboard side of the wheel hub, usually by being bolted to the inboard side of the wheel hub 70. The knuckle further comprises a steering arm 81 that extends from the inboard side of the knuckle 80. Wherein the knuckle 80 can be used to steer the wheel hub 70, and in turn the wheel 71, by turning the knuckle via pushing or pulling said steering arm 81. It is noted that the end of this steering arm, that is connected to the knuckle 80, is preferable off centre, as this will mean the force applied to the knuckle via the steering arm will similarly be off centre, which may help to increase the amount of rotational being transferred to the knuckle, thereby reducing the amount of force needed to steer the wheel. Further, the inboard side of the knuckle may include a port for receiving a pintle 60, or other component, to couple the knuckle to the rest of the suspension module. In the envisioned embodiments, said port in in the form of a hole/slot within the inboard surface of the knuckle, with a ring attached to the top and bottom of said slot, wherein the component can be placed within the slot and a rigid member, such as a rotatable shaft or bolt, can be passed through the ring and the component within the slot to couple the knuckle and component together. It is noted that the member used to couple the knuckle and component should be rotatable, so that the knuckle and said component can rotate independently, so that the movements of the component does not affect the knuckle, and therefore does not affect the steering/facing of the wheel hub 70, likewise the knuckle 80 and wheel hub 70 rotations would not affect the position and/or rotation of the coupled component. In the depicted embodiment the component coupled to the knuckle 80 is the pintle 60, in the depicted examples the pintle comprises two removable end portions 61,62 connected by a shaft, to couple to the pintle 60 to the knuckle 80 one end portion is removed, so that the shaft of the pintle can be passed through the rings, the removed end portion is the replaced to couple the pintle 60 to the knuckle 80.

Pintle 60: the pintle comprises two end portions 61,62 connected by a shaft or member. Wherein each end portion 61,62 comprises a pair of pegs, positioned on opposite sides of the end portions 61,62, wherein the longitudinal axis of the pegs is perpendicular the longitudinal axis of the shaft. It is preferable that these pegs be round, or have the ability to rotate around their longitudinal axis, as said pegs will be coupled to the end of a respective control arm 10,20, wherein said control arms 10,20 need to be able to rotate around the longitudinal axis of the pegs, either by having the pegs rotate with the arms, or using round pegs that allow the control arms 10,20 to rotate freely. Further, the shaft of the pintle is configured to be rotated around its longitudinal axis, the axis that is perpendicular to the longitudinal axis of the pegs, which in turn rotates the end portions 61,62 in the same direction. As mentioned, the end portions 61,62 will be coupled to the end of a control arm, therefore the rotation of the shaft can also rotate the control arms 10,20 around the shaft's longitudinal axis. By configuring the pintle 60 in such a manner the pintle can rotate the coupled control arms 10,20 in two perpendicular directions, thereby giving the control arms 10,20 two rotational degrees of freedom, allowing the control arms 10,20 to both adjust the ride height of the vehicle, and retract/extend, or both, depending on which axis is rotated. It is noted that the pintle 60 can be coupled to either the inboard or outboard ends 11,12,21,22 of the control arms 10,20, and may be positioned vertically or horizontally, defined by the direction of the shaft's longitudinal axis. However, it is preferable to have the pintle 60 coupled to the outboard ends of the control arms 12,22, in this configuration the pintle 60 can be coupled to the knuckle 80 as described above, removing the need for additional components to attach the control arms 10,20 to the knuckle 80 and to support the inboard pintle, the removal of such components can allow the modules to be more compact, especially when the wheels are retracted, reducing the amount of space each module needs to occupy, therefore freeing up more space within the vehicle for the occupants/cargo, and help to reduce the weight of the individual modules. It is also noted that the additional components, in particular the one to support the inboard pintle, may restrict the movements of the control arms, and by extension the movements of the module.

Raft 90: in the preferred embodiment, the modules include a raft 90 configured to couple the knuckle 80 to the pintle 60. To achieve this the raft comprises a pair of hollow shafts, that is a shaft, typically cylindrical, with a hole, or channel, that through the shaft's longitudinal axis, coupled together along their length. To couple the raft to the pintle 60 the shaft of the pintle is passed through the channel of one of the raft's shafts. To couple the remaining shaft to the knuckle 80, the second shaft is inserted into the slot on the inboard side of the knuckle 80, then a member, such as a bolt, is passed through the rings of the knuckle and the channel of the second shaft. It is noted that the shape of the raft's shafts is configured so that the knuckle 80 and pintle 60 can freely rotate around the longitudinal axis of the raft's shafts, without moving or rotating the raft 90 itself, thereby allowing the knuckle 80 and pintle 60 to rotate independently. This further reduces the risk of the movements of the knuckle 80 affecting the pintle 60, and vice versa, thereby preventing the pintle 60 from affecting the steering of the wheel hub 70, and preventing the knuckle 80 from rotating the control arms 10,20. This affect may be further improved by having the shafts of the raft be non-parallel, thereby ensuring that the rotational axis of the two shafts is similarly non-parallel thereby heling to prevent the rotation of one shaft affecting the other. The raft 90 may further configure a support arm 91, this support arm 91 will extend from the surface of the raft, usually from the point where the two shafts are connected, this support arm 91 can then be coupled to a frame, rod, or other supporting feature that can help prevent the raft 90 rotating when either the knuckle 80 or pintle 60 rotates. This further reduces the risk of the knuckle 80 and pintle 60 affecting the other as they rotate. The inclusion of the raft 90 help to improve the safety of each module as the knuckle controls the wheels tracking and steering, therefore if the pintle 60 causes the knuckle 80 to rotate, it may cause a loss of control of the vehicle, similarly the knuckle 80 rotations causing the pintle 60 to rotate, it may result in the control arms 10,20 moving which can cause a loss of control, as the wheel of one module retract or changes height out of order with the other modules, which could affect the vehicles grip or steering. Therefore, the inclusion of the raft 90 reduces the risk of such loss of control, when the module actuates.

Lower control arm 10 and upper control arm 20: the disclosed modules are designed to have a pair of parallel control arms 10,20, in most of the depicted embodiments the control arms 10,20 are positioned vertically, that is with one arm above the other, though it should be noted that the arms can be positioned horizontally, meaning the arms are positioned side-by-side. Regardless of the arrangement, the control arms 10,20 have a similar structure, with an inboard end 11,21 and outboard end 12,22 connected by a rigid arm. The structure of the control arm ends 11,12,21,22 depends on which component that end of the arm would be coupled to, as one end of each control arm 10,20 will be configured to be coupled to the pintle 60, while the other end is coupled to the body of the vehicle 160, or the knuckle 80 depending on whether the pintle is on the inboard or outboard end of the control arms.

Please note that in the case of the invention the term body, or chassis, of the vehicle refers to the structural frame of the vehicle, also in some embodiments components that couple to the chassis of the vehicle may be coupled to a support frame 230, which in turn is coupled directly to the chassis of the vehicle, typically by being bolted to the chassis. The end of the control arm that couples to the pintle 60 comprises a pair of rings, or ports, each of which receives one of the pegs, from one of the pintle end portions 61,62. The other end of the control arm, that is configured to couple to the vehicle or knuckle 80, comprises a member, or plug, that extends perpendicular to the length of the control arm, said plug may be inserted into a socket coupled to either the knuckle 80, the body of the vehicle 160, or a support frame 230 attached to the vehicle's chassis, these plugs are then secured in place by a nut, cap, or similar component that attaches to the end of the plug after it is inserted into the socket. Note that in some embodiments these plugs may be able to pivot slightly, via a ball and socket type connection between the control arm and the plug, this pivoting can reduce the risk of the plug breaking when the control arms rotate, by allowing the plug to adjust when the control arms 10,20 move. In most of the depicted examples the control arms 10,20 are identical, and though only a few example shapes for the arms are shown, any elongated design with the inboard and outboard ends 11,12,21,22 as described above would be suitable. In the preferred embodiment the control arms 10,20 are not identical, and include additional features to allow the control arms 10,20 to be directly coupled to the pair of actuators 120, 130, used to rotate said control arms 10,20. In particular the preferred embodiment of the lower control arm features a pair of ports 14, both near the centre of the control arm 10, with one on the upper surface of the control arm and one on the lower surface, wherein one end of each actuator will be coupled to a respective port 14 on the lower control arm 10. Note that these ports 14 could be positioned on either control arm 10,20, and may be anywhere along the length of the control arm, put would preferably closer to the centre of the control arm as this reduces the amount of force needed to move the control arm 10,20 when compared to the port 14 being at the ends of the control arm 11,12,21,22. In the preferred embodiment the upper control arm divides into two arms, or branches, that are connected at the ends of the control arm. These separate branches form a central hole, or aperture, in the arm, wide enough to allow the actuator that controls vertical rotations to pass through the upper control arm 20, so that it may couple to the port 14 in the lower control arm 10. Note that in the preferred embodiment, the vertical actuator is part of a dampener unit 30, therefore it is the entire dampener unit 30 that passes through the aperture of the upper control arm 20. This allows the mass of the module to be centralized, into the centre of the control arms 10,20, allowing each module to be more compact when the vehicle is lowered, and/or the wheels are retracted, it also distribute the weight of the module, in particular the dampener unit 30, more evenly, reducing the risk of damage to the control arms 10,20, especially when the vehicle has an impact which may push or jolt the suspension module, in particular pushing the dampener unit into the control arms, as when the dampeners or actuators are couples to the ends of a control arm this force, from the impact, may be sufficient to bend or even break the end of the control arm, which would then hinder the functions of the suspension module.

Track rod 100 and tie rod 110: both the track rod 100 and tie rod 110 comprise two end portions 101,102,111,112 connected by a rigid rod. It should be noted that each end potion of the track and fie rod comprises the same perpendicular member or plug connector, as described for the end of the control arms 10,20. Note that just like the control arms the plugs, the plug connecters of the rods can be secured with a nut or cap, and may be coupled to the rod via a ball and socket style connection to allow some pivoting of the plug, to prevent additional stress of the connection when the module is actuated, and therefore prevents the rod's connections from breaking. Also note that as depicted in the figures the plugs at the end of the track and tie rod may be positioned to point in the same direction, as shown for the track rod 100, or in opposite directions, as shown in the tie rod 110, depending on the modules specific design. Regardless of the direction of the plugs both rods function in the same manner. The track rod 100 is used to steer the knuckle 80, to achieve this the outboard end 101 of the track rod 100 is couple to the knuckle 80, or the knuckle's steering arm 81 if present, via the plug, with the inboard end 102 of the rod being coupled to a steering means that can push and pull the track rod 100, which in turn pushes and pulls the knuckle 80 allowing the module to be steered, there are different types of steering means available, such as a steering rack, but in the preferable embodiment the steering mean is in the form of a relay arm 140, which may also include a relay link 150 as described below. The tie rod 110 is used to provide stability to the module, with the inboard end 112 of the tie rod 110 being attached to the body of the vehicle 160, vehicle chassis, or support frame 230, while the outboard end 111 would be attached to the knuckle 80, or the raft 90, specifically to the support arm 91, if present. Like with the track rod 100 and control arm 10,20, the fie rod 110 would connect to the vehicle and the knuckle 80, or the raft 90, via the plugs attached to the respective end portion. The purpose of the tie rod 110 is to add extra stability to the module and to help support the weight of the modules various components. Additionally, the benefit of using the plug connections as described above, is that such connections will allow the track rod 100 and tie rod 110 to rotate around the plugs elongated axis, this will allow the rods to rotate with the control arms 10,20, and therefore remain parallel to the control arms 10,20 regardless of their position. By keeping the rods parallel to the control arms 10,20, the system reduces the risk of the rods breaking under additional stress when the control arms 10,20 rotate, and ensures that the rods do not obstruct the control arm's movements.

Relay arms 140 and relay link 150: as mentioned above the preferred steering means for the suspension module is a relay arm 140. Wherein the relay arm comprises a socket that connects to the body of the vehicle, the chassis of the vehicle, or a support frame 230 mounted to the vehicle, and an arm that extends from the side of the socket. Wherein the arm can rotate around the elongated axis of the socket in either a clockwise or anticlockwise direction. In some embodiments, the inboard end 102 of the track rod 100 would be coupled to the arm of the relay arm 140, wherein the rotations of the relay arm 140 pushes and pulls the track rod 100, in order to steer the wheel 71 coupled to the suspension module. In other embodiments, the relay arms 140 of adjacent modules may be connected via a relay link 150. The relay link 150 comprises an elongated plate, wherein the ends of the plate are coupled to a respective track rod 100, each of the track rods 100 being connected to a respective suspension module, in a pair of adjacent suspension modules 220. Wherein the adjacent relay arms 140 are coupled to the centre of the plate, via a pair of members, such as bolts or plugs, wherein the relay arms 140 can rotate to push or pull the relay link 150, which in turn pushes or pulls the connected track rods 100. The use of a relay link 150 would be preferable, as this may reduce the amount of force each relay arm 140 needs to supply to steer the wheels 71 attached to the suspension modules, additionally, the relay link may allow a single relay arm 140 to steer the pair of suspension modules 220 should one of the relay arms fail. It is also noted that the relay arms 140 are more compact than the other steering means, such as the steering rack, and therefore would allow the suspension module to become more compact when they retract, that is to say the modules will occupy a smaller volume when retracted.

First and Second Actuators 120,130: in the disclosed modules it is essential that the control arms 10,20 are able to rotate both vertically and horizontally, allowing the suspension modules to adjust the vehicle's ride height and retract the attached wheel respectively. To achieve these different rotation directions, the suspension module requires a pair of actuators 120,130, one controlling the vertical rotations of the control arms 10,20, and the other actuator controlling the horizontal rotations. Each actuator 120,130 comprises a spring actuator, so that each actuator can provide dampening to the suspension module regardless of the actuator position. Each actuator comprises a pair of end portions 121,122,131,132 connected by the spring actuator, each end portion comprising a connector suitable for coupling the end of the actuator to a component of the suspension module, specifically one of the control arms 10,20, and to the body of the vehicle 160, vehicle chassis or supporting frame 230 mounted to the body of the vehicle 160. Typically, the end portions of the actuators comprise a round, or disc-shaped connector, which includes a hole or aperture in the centre of the connector, these end portions are secured to other components by passing a member, such as a bolt or plug through the aperture in the centre of the connector, and through a similar hole or aperture in the component that the actuator is being secured to, the members are then secured by attaching a nut or cap to the ends of the members. The first actuator 120, which control the vertical rotation, has a first end portion 121 that is coupled to the body of the vehicle 160 above the suspension module, with a second end portion 122 couple to at least one of the control arms 10,20 as described above, preferably at a point between the end portions 11,12,21,22 of the control arms 10,20. The second actuator 130 which controls the horizontal rotations of the control arms 10,20, will be positioned horizontally, with an outboard end 131 coupled to one of the control arms 10,20, and an inboard end 132 coupled to the body of the vehicle 160, vehicle chassis or supporting frame 230 mounted to the body of the vehicle 160. Each actuator 120,130 can rotate the control arms 10,20 in a respective direction vertically or horizontally by expanding and contracting. It is noted that the rounded end portions are preferable as they will allow the actuators to rotate around the securing member, this prevents the connections being put under additional stress when the control arms rotate. Note that in the preferred embodiment, the first actuator 120, that controls vertical rotations, is replaces with an air-spring actuator contained within the dampener of a dampener unit 30, as described below. In all embodiments it is noted that the end portions 121,122,131,132 of the actuators 120,130 may be put under additional stress when the movement of the control arms forces the actuator 1320,130 to rotate in a direction that is perpendicular to the elongated axis of the member used to secure the end portions, this additional stress could potentially break the end portion, or the connection between the end portion and the other components. Therefore to reduce this stress, the end portions of the actuators connected to the body of the vehicle 160, may be mounted to a rotating joint, this may be in the form of a ball and socket connector, or a rounded bracket 231 that can rotate in the direction perpendicular to the elongated axis of the securing member, this will allow the actuator end portion to rotate with the same degree of freedom as the control arms 10,20, and therefore should not be put under additional stress as the control arms rotate.

Dampener unit 30 and support frame 40,50: as previously mentioned in the preferred embodiment the vertical actuator is replaced with a dampener unit 30, said dampener unit 30 comprises a housing that contains an air-spring actuator which can use an external hydraulic or pneumatic system to extend and contract said actuator, and adjust the amount of dampening provided by the dampener unit 30 by changing the fluid level within the dampener. It is also noted that the housing of the dampener unit is configured to expand and contract with the air-spring actuator within the dampener unit. The dampener unit 30 further comprises a first end portion 32 and a second end portion 31 connected by the dampener and housing, wherein each of the end portions 31,32 comprises a connector, typically the same disc-shaped connectors as described above for the actuators 120,130. Wherein the dampener is positioned vertically, with the lower/second end portion 31 connected to one of the control arms 10,20 and the top/first end portion 32 connected to the body of the vehicle 160, vehicle chassis or supporting frame 230 mounted to the body of the vehicle 160, at a position that is displaced vertically, above the second end portion 31. Note that the first end portion 32 may include a buffer or protective layer, that cover the top of the dampener unit 30, to prevent the dampener being damaged during an impact, should it collide with the body of the vehicle 160. It is noted that the first/top end portion 32 of the dampener may be connected to a rotating connector, coupled to the body of the vehicle 160 or mounting frame as described above. However, in some embodiments the dampener unit 30 may free standing, that is to say that the dampener unit is not connect directly to the body of the vehicle 160, instead the first end portion 32, would be connected to a dampener support frame which is then connected to the control arms 10,20, as a result the dampener support frame and dampener unit 30 is free to rotate horizontally, when the control arms 10,20 rotate horizontally, and makes the suspension module easier to remove for repairs, or maintenance, by removing one of the connections that would need to be tested and removed, when disconnecting the module. The support frame 230 would comprise a main stay 40, which has a cap portion 42 that covers some or all of the top end of the dampener unit 30, and may act as a buffer between the dampener and the body of the vehicle 160.

Note that this cap portion will connect to the first/top end portion 32 of the dampener via the disc-like connector using a securing member as described above. The main stay 40 then has a support arm that extend from the cap portion 42 along the length of the dampener unit 30, wherein the end of the support arm couples to the end portion 11,12,21,22 of one of the control arms 10,20, the end of the support arm uses a ring connector, wherein a securing member, such as a bolt or peg, passes through the end of the support arm, and the end of the control arm it is connected to, sometimes this member may also pass through the end portion 61,62 of the pintle 60, this securing member can then be secured using a cap or nut connected to the ends of the member. In some embodiments the end of the control arm that couples to the main stay 40 may include an additional connector, usually in the form of a rotatable plug, like the one used to connect the control arm 10,20 to the body of the vehicle 160, which will connect to the ring connector at the end of the support arm of the main stay 40. Regardless of which connector is chosen, both options will allow the main stay 40 to rotate around the elongated axis of the connecting plug, or member, allowing the main stay 40 to rotate vertically around the connector, as the dampener unit 30 expands and contract, thereby reducing the stress on the main stay 40. The dampener support frame may also comprise one or more secondary stays 50, comprising two end portions 51,52 connected by a rigid member, these end portions comprising a ring connector, wherein the first end 52 of the secondary stay 50 is secured to either the top end 32 of the dampener, or the cap portion 42 of the main stay 40, by passing a bolt, screw or other member through the connector and either the end of the dampener or main stay 40, the other end of the secondary stay will then connect to the end of one of the control arms 10,20, in the same manner as the support arm of the main stay 40. It is noted that the main stay 40 and the secondary stays 50 may be connected to different control arms 10,20 to more evenly distribute the weight of the dampener unit 30 across both control arms 10,20, reducing the risk of damage from the dampener to the control arms during an impact, and the force created by the impact will be more evenly distributed.

Body of the vehicle 160: in the various illustrated examples of the invention a specific vehicle type has been depicted, though as noted in the application the claimed suspension module is suitable for an array of wheeled vehicles, which may be of a different size or shape to the one shown and may possess any number of wheels, each wheel requiring its own suspension module. Throughout the application the term 'body/chassis of the vehicle' refers to the physical structure of the wheel vehicle, in particular the solid frame or exterior of the vehicle, which the suspension module components can be safely secured to. This connection to the body of the vehicle may be formed directly between the module and the body of the vehicle, or the components may be secured to a support frame 230, wherein the frame can then be mounted to the underside of the vehicle's body/chassis, typically using bolts or other suitable means.

Mounted Support frame 230: in the various embodiments of the disclosed suspension module there are components which are configured to be coupled to the body of the vehicle, such as the inboard ends of the tie rod 110 and control arms 10,20, though these features can be mounted to the vehicle directly as described above, it may also be desirable to use a mounting frame to secure the suspension modules, as said frame can be easily adapted to different vehicle shapes/sizes, without the need to alter the suspension module itself. Through the depicted examples only show a wedge-shaped support frame, it is understood that the support frame may have a different shape, as necessary to fix onto the underside of the body of the vehicle 160. The inboard components of the suspension module would be secured to the frame using the plug connections described above being inserted into hold within the support frame, and then secured with a bolt or cap. Other components, such as the horizontal actuator 130, which uses a ring or disc-shaped connector, will be secured by passing a member, such as a bolt, through the connector and into a hole within the mounting frame 160, before the ends of the member are secured using a nut or cap. In some embodiments the frame may include additional components/connectors for affixing the components of the module to the support frame to allow more degrees of rotation, such as the rounded brackets 231 used to secure the inboard end of the horizontal actuator 130 to the support frame 230, that can rotate in the direction perpendicular to the elongated axis of the member securing actuator to the frame, as described earlier to allow the different connections between the frame and the module to rotate as the control arms rotate to reduce the stress on these connections and help ensure they do not break when the control arms 10,20 move. After which the frame may be mounted to the underside of the vehicle, typically using bolts that will pass through a plurality of holes in the support frame and into the underside of the vehicle's body or chassis.

Fused/shear bolts 240: in some embodiments the members, or bolts, used to secure the components of the suspension module to the support frame 230, or the body of the vehicle 160, may be design to break when subjected to sufficient force. This can be achieved by using members with a weak point, said weak point comprising inlets, or breaks in the members surface, wherein the member will break at the point with these inlets when a predetermined amount of force is applied, via an impact on the vehicle. Such members may be used to ensure that when a suspension module is impacted with a force that would be sufficient to damage either the wheel 71, wheel hub 70, or one or more of the control arms 10,20, track rod 100 or tie rod 110, the module will break away from the vehicle, to ensure that the damaged module does not hinder the performance of the vehicle, or fly apart and cause further damage to the vehicle.

Detailed description

The present invention provides a wheeled vehicle comprising a plurality of wheel assemblies, most commonly a vehicle would comprise of four of these assembles but the mechanisms and methods described below could apply to any number of modules on a single vehicle. Each of these wheel assemblies are comprising an adjustable suspension module, mounted upon suspension arms, herein referred to as control arms 10,20, that can pivot in both the vertical and horizontal direction relative to the body of the vehicle 160 as to adjust the position of the wheel attached to the assembly, by both adjusting the height of the wheel and by retracting the wheel. Said pivoting would be controlled via a pair of actuators 120,130 coupled to at least one of the control arms 10,20. Wherein the first actuator 120 controls vertical rotations, while the second actuator 130 controls horizontal movements.

These motions of the suspension module can be used to adjust the vehicle suspension to better overcome different types of obstacles and terrain, by adjusting the profile and wheel base of the vehicle to better suit the terrain it is traveling over. For example, of smooth or open terrain it may be preferable for the vehicle to have a lower profile for improved aerodynamics. While on rough, uneven terrain the vehicle will preferably have a higher profile to prevent the body hitting the terrain, and a wide wheel base to improved stability.

Further the actuators 120,130 used to move the suspension during these adjustments can utilise different types of systems, such as hydraulic, pneumatic or electrical systems, to actuate them. Note that these systems can have different arrangements, for the system may be a centralised system that connects to each actuator, or there may be a separate system for each actuator, or each suspension module, or a plurality of systems wherein each system controls a single pair, or select group of modules within the suspension system. It is also noted that it is preferable for the actuators 120,130 to be in the form of spring actuators, so that each actuator has a degree of compliance, that can help deflect the force of impacts caused by obstacles and rough terrain. Further the hydraulic, pneumatic or electrical systems, can be used to adjust the set point of the spring actuator, this changes the property of the actuator, such as the volume or spring constant, to provide a desired amount of compliance regardless of the actuators position/length at the time. For normally the actuator would have a lower compliance when compressed, and a higher compliance when extended. Therefore, it is desirable to have the ability to change the setpoint to provide more, or less, compliance when necessary. Note that the less compliance an actuator has the more dampening it may provide to prevent movements in the suspension system, which may be preferable when the vehicle is on a on smoother surface such as a road, but can leave the suspension more susceptible to impacts.

Figure 1 depicts examples of different types of roads surfaces a wheeled vehicle may have to traverse. As shown in the examples, surfaces could rise, lower, be sloped or have breaks or ditches within the surface. Therefore, the vehicle will include sensors attached to the vehicle, that will be able to provide data to a processor within a controller, so that the processor will be able to determine the features of the surface and recognise the profile of the surface. Then the controller can adjust the wheel height of each module to match the profile of the surface. This will reduce the impact changes in the surface will have on the profile/ride height of the vehicle, thereby making the ride more comfortable for the occupants. In particular, by allowing the wheels 71 to remain in contact with the road surface at all times, and reducing the impact of any obstacles and uneven surfaces on the wheels 71. This system may also allow the vehicle to traverse situations it may otherwise have been unable to, such as fording deep rivers by lowering all the wheels, or traversing small urban environments by lowering the suspension and retracting the wheels, among others.

Further the sensor data can help determine if there are any obstacles in the vehicles path, such as rocks, debris or any walls that would narrows the drivable surface. Once the obstacles are identified the controller can use the height adjustment mechanism, and/or wheel retraction mechanism of the suspension module to move the wheels 71 away from the obstacle to avoid contact with said obstacle. If this is not possible the system can instead use these mechanisms to adjust the wheels 71 to a position where the impact with the obstacle will be minimised, such as by having the wheel 71 follow the profile of the obstacle in the same manner as it does the road surface. Additionally, in response to the determination of an obstacle that cannot be avoided, if the suspension is using a spring actuator, the controller may use the hydraulic, pneumatic or electrical system controlling the actuator, to increase the compliance of the actuators 120,130, by changing their respective set point, to better deflect the force of the impact. It is noted that a spring actuator in this case refers to an actuator containing a resilient member, which may be for example an air-spring, that can provide shock absorption or force deflection to the actuator.

It is also noted that the sensor data can be used to determine if the surface the vehicle is travelling over is smooth, such as a road, or rough, such as over off-road paths. In this case rough can be defined by surfaces with many changes (breaks, slopes, rises and fall) or many obstacles in quick succession. Once the type of surface is determined the controller may set the suspension to one of several modes, suitable for that type of surface. For example, on a smooth surface the profile may be lower, while on a rough surface the profile is higher, the wheel base is wider and the compliance of the actuators is higher, as described above. Note these modes may also be chosen by user input, either using onboard vehicle controls, a remote control, or an application on a mobile device To achieve these effects, the system uses one or more sensors mounted to the body of the vehicle or to the suspension module itself. These sensors are configured to either scan the surface the vehicle is traveling over, or to monitor the conditions of the suspension modules, detecting any movements in the module or force applied to them. Some examples of sensors that can be used includes a camera mounted to the body of the vehicle 160, an accelerometer attached to the wheel hub (70), or a stress meter attached to the control arms 10,20.

Figures 2 to 4 shows examples of parts that can be used to form the suspension module used in the invention. Figure 2 shows all of the parts for making the preferred embodiment of the suspension module. These parts include a wheel hub 70 for coupling to the wheel 71, a knuckle 80 that couples to the inboard side of the wheel hub 70 for coupling the other components of the suspension to the wheel hub 70. The knuckle 80 can also include a steering arm 81 that couples to any suitable steering means, to provide steering to the wheel hub 70. in the preferred embodiment this steering is provided by a track rod 100 with one end rotatably coupled to the steering arm 81, and the other end rotatably coupled to a steering means, which in the case of the preferred embodiment is a relay link 150 coupled to a pair of relay arms 140. The track rod 100 required rotatable ends so that it can stay parallel to the control arms 10,20 of the suspension module as they rotate, this allows the rod to provide both steering and addition support to the module regardless of the wheel hub's position.

The module can optionally include a raft 90, that rotatably couples to both the knuckle 80 and a pintle 60. The raft 90 comprising a pair of joined cylinders, with a hole running the length of the cylinders' longitudinal axes. The raft 90 tis coupled to the pintle 60 by passing the pintle 60 through one of the cylinders, then the other cylinder is coupled to the knuckle 80, this can be achieved by passing a ridged member through the knuckle and second cylinder. The raft 90 allows the knuckle 80 and pintle 60 to rotate independently, allowing the wheel hub 70 to keep its track/facing as the suspension adjusts allowing the modules to be adjusted while the vehicle is moving without affecting the steering. Therefore, it is preferable for the raft's cylinders to be non-parallel, as this will ensure that the rotational axes of the knuckle 80 and pintle 60, are similarly non-parallel which will reduce the risks of the rotation of one affecting the other.

To assist the raft 90 further in this function, the raft 90 may include a support arm 91 coupled to a fie rod 110. The tie rod 110 has one end rotatably coupled to the raft 90, via the support arm 91, but may also attach to the knuckle 80 if there is no raft, with the other end rotatably coupled to the body of the vehicle 160. The tie rod 110 provides additional support and may prevent unwanted rotations in the module. Again, the ends of this rod need to be rotatable, just like the track rod 100, so that the rod can move to stay parallel to the control arms 10,20 to provide better support. As mentioned, the module includes a pintle 60, this pintle 60 coupled to either the inboard ends 11,21, or the outboard ends 12,22 of the suspension's control arms 10,20, and is configured to allow the control arms 10,20 to pivot both vertically and horizontally. To achieve this the pintle 60 comprise two end portions 61,62 connected by a ridged member, wherein in the rotation of the ridged member, around its longitudinal axis, will rotate the control arms 10,20 in one direction, which is the horizontal direction in the preferred embodiment. While the end portions are configured to also control arms to rotate in the direction perpendicular to the pintle's longitudinal axis, in the case of the preferred embodiment this is achieve by the round pegs on either side of each end portion 61,62.

The suspension modules will also comprise a pair of parallel control arms 10, 20, in the preferred embodiment these arms will comprise an upper 20 and lower 10 control arm, displaced vertically from each other, though they may be displaced sidewards from each other instead, thereby comprising a left and right control arm instead. Wherein each control arm 10,20 comprises an inboard end 11, 21, pivotably coupled to the body of a vehicle 160, and an outboard end 12, 22 coupled directly or indirectly to the wheel hub 70. Note that in the case of the invention the term parallel is defined as the control arms 10,20 being maintained parallel to one another, such that the ends of one of the control arms remain equidistant from the same end of the other control arm when the control arms 10,20 move.

The modules also comprise a pair of actuators 120,130, with one end coupled to the suspension module, preferably to at least one of the control arms 10,20, with the other end coupled to the body of the vehicle 160. The first actuator 120 is configured to pivot the control arms 10,20 vertically, while the second actuator 130 is configured to pivot the control arms 10,20 horizontally. To this end it is preferable to have the actuators 120,130 couple to the control arms 10,20 between the inboard ends 11,21 and outboard ends 12,22, as such a geometry can help reduce the force needed to pivot the control arms 10,20 and allow greater control. Therefore, the control arms 10,20 may include sockets or ports along their length, suitable to be rotatably coupled to the end of the actuators 120,130. As previously mentioned, it is preferable that these actuators 120,130 be in the form of spring actuators, controlled using one of a hydraulic, pneumatic or electrical system, as such actuators can provide improved compliance for impact deflection, by using the system to change the actuators set point independent of the actuators length. Note that the hydraulic system is the least preferable as it will require a reservoir within the vehicle, adding unnecessary weight.

Further each module comprises a dampener 30, wherein one end 31 of the dampener 30 is rotatably coupled to at least one of the parallel control arms 10,20, and the other end is configured to be rotatably coupled to the body of a vehicle 160, likely using a ball joint. Said dampener 30 is preferably resiliently extendible and compressible for accommodating the movement of the suspension arms when in use. It is also preferable for the dampener 30 to be adjustable in use, to increase or decrease its length and in that function, allowing it to operate as the first actuator 120. The dampener 30 would thereby pivot the parallel control arms 10,20 vertically relative to the rest of the vehicle, by said resilient extension and compression moderating the forces transmitted from the wheels to the vehicle for providing the suspension. It is also preferable to have the dampener 30 not attached to the body of the vehicle 160 at all, as this will allow the dampener 30 a greater range of motion, and will allow the dampener 30 to rotate with the control arms 10,20 when they pivot horizontally, this ensures the broadest range of motion for the control arms 10,20, and prevents the dampener 30 from being damaged, by being stretched or twisted when the control arms 10,20 move, due to being anchored to the vehicle's body. To achieve this the end 32 of the dampener 30 remote from the control arms 10,20 can instead be coupled to a support frame comprising a stay assembly.

The stay assembly comprising two or more stays 40,50 being elongate members, a first stay being attached at one end 41 to one of the ends 11,12,21,22 of a control arms 10,20, preferably the inboard end 11 of the lower control arm 10, with the other end 42 of the first stay 40 coupled to the end 32 of the dampener 30 remote from the control arms 10,20. Additionally, there are one or more secondary stays 50, the secondary stays 50 having one end 51 rotatably couple to one end 11,12,21,22 of a control arms 10,20, preferably the inboard end 21 of the upper control arm 20, with the other end 52 of the secondary stays 50 rotatably coupled to either the remote end 32 of the dampener 30 or to the remote end 42 of the first stay 40. This structure of the stay assembly thereby provides a fixed attachment point to one or both of the stays 40,50 for the remote end 32 of the dampener 30. The structure of the stay assembly can also help distribute the weight of the dampener 30 over the suspension module, and help transfer force from the dampener 30 to the control arms 10,20, when the dampener 30 is acting as the first actuator 120, Figure 3 depicts examples of control arms 10,20 and actuators 120,130 that can be used in a simpler suspension module, whereas Figure 4 depicts the control arms 10,20, actuating dampener 30 and stays 40,50 for the stay assembly that would be used in the preferred embodiment as described above. Note that in the preferred embodiment the second actuator 130 is the same as the one depicted in Figure 3. Also, it is noted that in the preferred embodiment, the upper control arm 20 is configured to include an aperture, so that the dampener 30 may pass through the upper control arm 20, and couple directly to a port 14 in the lower control arm 10. By doing this the dampener 30 is brought into the centre of the suspension module, this helps balance the weight of the suspension module, reduces the overall volume of the module so that the retractable wheels will use up less of the interior volume of the vehicle, and provides an improves geometry wherein the dampener 30 can more easily move and rotate with the control arms 10,20, while not hindering the control arm's range of motion.

Figure 5 shows examples of the preferred embodiment of the module. Specifically, a pair of modules, including a wheel 71 attached to each wheel hub 70. note also that the track rod in each module is joined together using the aforementioned relay link 150, to provide better steering to both modules, as there will be better control, and because if one of the relay arms 140 fails the link will allow the lone relay arm to steer track rods 100.

Figure 6 shows the parts of the preferred module that are used in the height adjusting mechanism. Specifically, the control arms 10,20 and the dampener 30 acting as the first actuator 120. Figure 7 shows the actual hight adjustment mechanism, in particular it depicts the module at three different stages lowered, normal and raised. In the lowered position the dampener 30 has been compressed, which pivots the control arms 10,20 downwards relative to the wheel hub 70. By adjusting all of the modules on a vehicle to this position the profile of the vehicle can be lowered. Alternatively, if a single, or select number of modules is adjusted to this position, those wheels will be raised relative to the other wheels attached to the vehicle. In the raised position the dampener 30 has been expanded to pivot the control arms 10,20 upwards relative to the wheel hub 70. By adjusting all of the modules on a vehicle to this position the profile of the vehicle can be raised. Alternatively, if a single, or select number of modules is adjusted to this position, those wheels will be lowered relative to the other wheels attached to the vehicle.

It is noted that in this embodiment of the module, the dampener 30 comprises a housing that can expand and contract, the housing containing a dampener and a resilient member, wherein the resilient member can allow the dampener to expand and contract to allow the dampener 30 to act as an actuator, in particular a spring actuator. To do this the dampener may, for example, comprise an air spring, as the resilient member. The resilient member is controlled using one of a hydraulic, pneumatic or electrical system. The chosen system will not only expand and contract the actuator, but is also configure to adjust the set point of the resilient member. It is understood that this resilient member will provide a certain amount of compliance when impacted, allowing the module to move so as to deflect the force of the impact, and that this compliance is greater when the member is extended compared to when it is contracted, due in part to the greater range of motion available to the member, this can be visualised by imagining the resistant member as a spring, which has a greater degree of motion when stretched, compared to when it is compressed. However, by using a resilient member such as an air spring the system can adjust other variables, such as the amount of fluid in the dampener 30 or the volume of the housing being used, to adjust the properties of the air spring such as its spring constant, to provide a desired amount of compliance independent of the members length. By increasing the compliance of the actuator 120,130, or dampener 30 in this case, the suspension has improved impact deflection due to the freedom of the module to move in the direction of the force of the impact, thereby redirecting the force of the impact away from the suspension. This allows the suspension to provide improved comfort to the vehicle's occupants, and improved steering/control after an impact, as said impact will have a reduced effect on the vehicle, due to the reduced force being transferred to the vehicle itself. This is why a higher compliance is preferred when the vehicle is traveling over rough terrain, where there will likely be may impacts upon the suspension. In these situations, it is also preferable to raise the vehicles profile, as this will raise the body of the vehicle 160 to reduce the chance of impact to the body itself, and by extending the dampeners 30 with this motion the compliance in the suspension will be increased further.

Figure 8 shows the effects the different module positions in figure 7 can have on the profile of a vehicle, as described above, the lowered state of the module will lower the profile of the vehicle as shown in the left image of figure 8, this can be preferable when traveling over smooth or open terrain, to improve the speed of the vehicle by improving the aerodynamics, and can assist the vehicle in traversing small spaces such as those in an urban environment.

Whereas, when the modules are in the raised position, the profile of the vehicle is raised as shown in the right image of figure 8, again this can help in traversing rough terrain by raising the body over obstacles and by increasing the compliance of the suspension, this higher profile may also allow the occupants or the sensors to see over obstacles that would otherwise obstruct the field of view.

Figures 9 and 10 show alternative uses for the height adjustment mechanism, here instead of altering all the modules together to change the vehicles profile, only one module, or a selection of modules are being adjusted to raise or lower a specific wheel 71, or specific selection of wheels. In the displayed examples the wheels on one side of the vehicle are being raised, this may be done to match the profile of the sloped surface the vehicle is on, or to raise specific wheels over an obstacle. The system may also raise a select wheel 71 in this manner to reduce the impact when hitting an obstacle that cannot be avoided, as the rolling friction of the now free spinning wheel on the surface of the object can help reduce the transfer of force to the wheel 71 and by extension the suspension system. This adjustment of individual wheels is also how the system is able to match the profile of different surfaces, such as those in figure 1, by raising or lowering select wheels to a required height.

Figure 11 shows the parts of the suspension module need for the wheel retraction mechanism, in particular the control arms 10,20 and the second actuator 130. The figure also depicts the track rod 100 and steering arm 81 attached to the knuckle 80, to show how the track rod 10 rotates with the control arms 10,20 so as to provide steering regardless of the position of the suspension module. As depicted the second actuator 130 can expand and contract to rotate the control arms 10,20 horizontally relative to the wheel hub 70. In doing so the angle between the control arms 10,20 and the longitudinal axis of the vehicle can be decrease to retract the wheel into the body of the vehicle 160, or increase to expand the wheel away from the body of the vehicle 160.

This mechanism can be used to retract the wheels of the vehicle to allow the vehicle to travel through narrow passages, such as those in an urban environment. It may also be used to move one or more wheels out of the path of an obstacle to avoid impacts. it may also be used with the hight adjusting mechanism to reduce the vehicles size to make it easier to store and transport the vehicle, for example in a shipping container or train carriage, by lowering the vehicle's profile and retracting all the wheels to reduce the vehicles wheel base.

It is also noted that this mechanism can be used to make small changes to the position of individual wheels, or individual pairs of wheels to improve steering during a turn, to reduce the effects of oversteer or understeer determined using the sensor data. It is also noted that the length of the control arms can be designed to improve the Ackerman value of the suspension following Ackerman geometry, by changing the kinematics of the suspension module.

Further, on rough terrain all of wheels of a vehicle can be extended to widen the vehicles wheel base, to improve stability. Also, when the wheel base is increased, the second actuator 130 of each module is extended, this means that the second actuators 130 will have a higher compliance for impact deflection. Also, as noted with the height adjustment mechanism, it is preferable for the second actuator 130 to be a spring actuator comprise a resilient element, such as an air spring, controlled by a hydraulic, pneumatic or electrical system. This is so the system can be used to adjust the set point of the second actuator 130, to provide a desired amount of compliance independent of the actuator's length, as described above, this is used to help traverse different type of terrain, or to reduce the effects of an unavoidable impact.

Figure 12 shows the wheel retraction mechanism for a complete pair of suspension modules 220, using the preferred embodiment for the suspension module. The figure shows how the dampener 30, fie rod 110, track rod 100 and control arms 10,20 all rotate together, when the mechanism is used to retract or expand the attached wheels 71. By keeping all the rods 100,110 and control arms 10,20 parallel, the rods 100,110 are able to provide support and steering regardless of the position of the control arms 10,20. Also, by rotating the dampener 30 with the control arms 10,20, the dampener 30 is able to perform at its full efficiency regardless of control arms' position, meaning the amount of force the dampener 30 needs to apply to the control arms 10,20 does not change with the movements of the suspension system.

Figure 13 shows the wheel retraction mechanism being used for a pair of wheels, and then for all the wheels in the system. As mentioned all the wheels 71 can be extracted or expanded at once to change the wheel base of the vehicle, either reducing the wheel base to manoeuvre through small areas, or widen the wheel base for improved stability and suspension compliance. It is also noted that the system may retract an individual pair of wheels to avoid an obstacle, or in some cases to improve the vehicle performance in terrains such as snow or mud, by having each wheel travel in different parallel paths, thereby ensuring each wheel 71 has its own path and does not become stuck in the trench made the more forward wheels.

Figure 14 shows the retraction mechanism from figure 7 being used to retract all the wheels simultaneously on an example vehicle. It is noted that with the inclusion of the raft 90 in the suspension module, changes like the ones shown in the example vehicles in figures 8, 9, 10 and 14 can be made while the car is still in motion, such changes being done either automatically preformed in response to data information received from the onboard sensors, or other sources such as a GPS signal or signal from a remote control or mobile device, or in response to the user's command received by onboard controls. The raft 90 also allows the system to make changes while the vehicle is turning, these changes may include changes to the wheels position to counteract the effects of slipping, such as oversteer and understeer, as the raft 90 prevent the changes to the control arms 10,20 from affecting the facing of the wheel 71, and also prevents the turning of the wheel 71, specifically turning of the knuckle 80 from affecting the rest of the suspension, which can negatively affect the Ackerman value of the suspension, determined by the vehicles kinematics, as the vehicle turns.

Figure 15 shows other examples of suspension systems using the preferred embodiments of the suspension modules. Specifically, it shows how systems may include more than four wheels, in this case a six wheeled system and eight wheeled system are also shown. It should be noted that regardless of the number of modules the same mechanisms are used to adjust the height, width or compliance of each module, either individually, in select groups or all at once simultaneously, providing the same benefits described above. It should also be noted that the system may also be programmed to raise, and possibly also retract, wheels considered redundant to the system. This may include wheels that are determined to be damaged based on data received relating to an impact to said wheel, or the centre wheels in a system with more than four wheels. Doing so can reduce the vehicles overall friction for better speeds, especially on smooth surfaces, and prevent further damage to a damaged wheel.

It is also noted that in the above-mentioned systems the wheel hub 70 may also include a motor for driving the wheel 71, and controlling the braking for said wheel 71. The motor my use electrical or hydraulic systems to drive the wheel, which may be connected to the same system driving the actuators 120,130. Note that if electronic systems are used then the wheel hub 70 will need to use the vehicle's cooling system to cool the wheel hub 70, while a hydraulic system may use its own fluid for this purpose. In such systems the suspensions mode may include limitations on the speed of the wheels, and the system may adjust these limits based on the received data. Also as noted individual wheels may have their speeds adjusted in response to the sensor data, in order to reduce the force transferred to the suspension system during an impact, this will further improve the vehicles' ability to traverse rough terrain, with a reduce risk of damage to the vehicle and improved comfort for the occupants. It may also use different speeds for different wheels to assist with steering on rough or loose terrain, or to help counteract the effects of oversteer or understeer on the vehicle.

Another thing to note is when the vehicle initially starts the suspension system will be set to one of the predetermined modes. This may be a mode chosen based on the current surface data from the sensors, a mode chosen by the user, or a mode determined from GPS information indicating the type of terrain on the vehicles planned path. Each mode will set initial values, thresholds and limits for the vehicles speed, profile and wheel base, and also the suspensions compliance, which may be changed by user's input, or in response to certain data, such as a change in the terrain type, or a priority set by the user. These priorities can include speed or comfort, with the limits changing to provide higher speed or more force deflection based on the option chosen.

Figures 16 and 17, show an example means of coupled the disclosed suspension modules to a wheeled vehicle. Specifically, Figure 16 depicts a mountable support frame 230 wherein the inboard end portions of the suspension module components, in particular the control arms 10,20, track rod 100 and tie rod 110, are coupled to the support frame, using bolts, or any other suitable means. Note that the support frame may comprise additional parts, such as the rounded brackets 231, to allow the components coupled to the frame to rotate relative to the support frame. Then the mounting support frame 230 can be mounted to the underside of a vehicle, as depicted in figure 17, using additional bolts, or another suitable means.

By using the suspension system described above, the invention provides a vehicle that can automatically adapt to a wide range of different terrains, from smooth open roads, to jagged off road environments, to compact urban streets. By having the system automatically adjust the wheel base and suspension hight to best suit the current driving surface to provide maximum comfort to the vehicles occupants. Additionally, these features improve the stability of the vehicle, by attempting to keep the vehicles body at a consistent height there is a reduce risk of the vehicle's occupants be thrown around within the vehicle, when traversing uneven terrain, allowing the driver of the vehicle to keep control more easily. This is achieved because the system automatically adjusts the vehicle's wheels to try and match the profile of the current surface, thereby keeping the body of the vehicle 160 at a constant height, even when the surface beneath it is uneven. It is also noted that the adjustments to the wheel base and ride height of the vehicle, based on the current terrain can help improve the dynamics and performance of the vehicle, for example by improving the vehicle's aerodynamics, by lowering the vehicles body when driving over a smooth surface, or adjusting the shape of the vehicle's wheel base to provide better grip of a slippery surface, such as mud, or to provide improved turning. It is also noted that the disclosed system can help a vehicle to traverse areas that it otherwise could not, for example the vehicle can now reduce its size to fit into smaller spaces, but may also use the movements of the individual wheels to traverse trenches that were otherwise, too steep, broad or deep, by using the adjustable wheel hight to assist in climb such a trench. The system also improves driver safety, as the system can adjust the wheel position and the amount of suspension dampening, in order to avoid impacts, or reduce the effects of unavoidable impacts by deflecting the force away from the vehicle, with the system being able to predict such impact a react more quickly than the user, and may be able to determine impacts that the user could not, for example due to low visibility. It is also noted that with the use of sensors and a controller, all of these changes to the suspension can be carried out automatically, even when the vehicle is in motion, without the need to stop the vehicle or make manual adjustments, this can be particularly useful when the vehicle is travelling at high speeds, and/or traversing a dangerous environment, wherein the user would not wish to stop or leave the vehicle.

Claims

Claims: 1. A suspension system for a wheeled vehicle comprising one or more suspension modules; wherein each module comprises: a pair of parallel control arm (10,20), with the inboard ends (11,21) of the control arms (10,20) are rotatably coupled to the body of a vehicle (160), and the outboard end (12,22) of each arm is rotatably coupled to a wheel hub (70), via a knuckle (80) on the inboard side of the wheel hub (70); wherein the inboard or outboard ends (11,12,21,22) of the control arms (10,20) are coupled together by a pintle (60), wherein the pintle (60) is configured to allow the control arms (10,20) to pivot vertically and/or horizontally relative to the wheel hub (70); wherein the wheel hub (70) comprises an optional motor; wherein the pintle (60) is coupled to the knuckle (80) by an optional raft (90); a dampener (30) coupled to at least one of the control arms (10,20); a pair of spring actuators (120,130), comprising a first actuator (120) and a second actuator (130); each actuator having one end rotatably coupled to the body of the vehicle (160) and the other end rotatably coupled to at least one of the control arms (10,20); wherein each actuator is actuated by either a hydraulic, pneumatic or electronic system; one or more sensors, wherein the sensor can be mounted to either the body of the vehicle (160), the wheel hub (70) or one of the control arms (10,20), and is configure to monitor the surface the vehicle is traveling on, the pressure of the modules wheel, or the movement of the suspension module a controller configured to process the data received from the sensors, and process user inputs, and is configured to control the suspension modules using the pair of actuators (120,130) based on determinations from the received inputs.
2. The suspension module of claim 1, wherein the dampener (30) and first actuator (120) are replaced with a dampener unit, the dampener unit comprising a housing containing a spring actuator, such as an air spring, and is configured to dampen the movements of the suspension module; and further configured to act as the first actuator (120) by using the spring actuator to expand and contract the dampener (30) along its longitudinal axis.
3. The suspension module of claim 1 and 2, wherein the parallel control arms (10, 20) comprise an upper control arm (20) and a lower control arm (10), with the upper control arm (20) positioned above the lower control arm (10).
4. The suspension module of claim 3, wherein the upper control arm (20) comprises an aperture configured to allow the dampener (30) to pass through the upper control arm (20), between the inboard and outboard ends (21,22) of the upper control arm.
5. The suspension module of claim 3 or 4, wherein the lower control arm (10) includes a port (14), positioned between the inboard and outboard ends (11,12) of the control arm (10), the port (14) is configured to be coupled directly to one end (31) of the dampener (30).
6. The suspension module of any preceding claims, wherein the one or more sensors comprise at least one of a camera coupled to either the body of the vehicle (160) or the wheel hub (70), an accelerometer coupled to the wheel hub (70), or a pressure gauge mounted to the wheel hub (71) configured to monitor the pressure of the wheel (71) coupled to said wheel hub (70), or a stress meter couple to at least one of the control arms (10,20).
7. The suspension module of any preceding claims, wherein the knuckle (80) further comprises a steering arm (81), that is rotatably coupled to one end of a track rod (100), with the other end of the track rod (100) being coupled to a steering mechanism, such as a relay arm (140), either directly or by a relay link (150); wherein the rotatable ends of the track rod (100) allow the rod to rotate so that it is parallel to the control arms (10,20).
8. The suspension module of any preceding claim, wherein the module further comprises one or more tie rods (110) for providing support; wherein one end of the tie rod (110) is rotatably coupled to the raft (90), an optional support arm (91) of the raft (90), or the knuckle (80), with the other end rotatably coupled to the body of the vehicle (160); wherein the rotatable ends of the tie rod (100) allow the rod to rotate so that it is parallel to the control arms (10,20).
9. the suspension module of any preceding claims, wherein the module further comprises one or more mountable support frames (230), for mounting the suspension module to the body of the vehicle (160).
10. A method of using the suspension system of any proceeding claim, the method includes: The controller receiving a user input, or GPS data for the planned route, to set the suspension modules into a desired mode suitable for the expected terrain; wherein to set the mode, the controller uses the first and second actuators (120,130) to set each module on the vehicle to a desired height, and/or extend or retract each wheel to provide a desired wheel base; the controller uses a hydraulic pneumatic or electrical system to actuate the pair of actuators (120,130) to adjust each suspension module; then the controller can use the same hydraulic, pneumatic or electrical system to adjust the set point of each actuator, allowing the actuators (120,130) to provide a desired amount of compliance/dampening; the controller can then receive further user inputs to adjust the position of the wheels, the compliance of the suspension or the height of the vehicle to a desired level after the mode is set; also, the controller can receive data from the one or more sensors, using the data the controller can determine the condition of the surface the vehicle is travelling on, and/or determine the location of obstacles in the vehicles path, such as rocks or debris; based on the determinations from the sensor data, the controller can adjust the suspension modules automatically, by adjusting at least one of the wheel height, the wheel extension or the actuator set point, to avoid the obstacle if possible, or to increase the modules compliance to reduce the effect of any impacts that cannot be avoided, to reduce the effect on the occupants of the vehicle.
11. The method of claim 10, wherein the controller receives GPS data to determine the expected terrain at each point of the route, adjusting the suspension mode based on the expected terrain while the vehicle is moving between these points.
12. The method of claims 10 and 11, wherein the sensor data is used to determine if the surface the vehicle is on is smooth or rough; On determining the surface is smooth, the controller will do at least one of lower the height of the vehicle, and/or reduce the compliance of the suspension modules, to a predetermined level; On determining the surface is rough, the controller will do at least one of raise the height of the vehicle, widen the vehicle wheel base by extending the wheels, limit the wheel speed and/or increase the compliance of the suspension to a predetermined level.
13. The method of claim 12, wherein on determining the terrain is rough, the controller can use the sensor data to determine the severity to which the surface is rough; The severity can be determined to be high, if there are more obstacles or changed in the surface the vehicle is on within a certain length, or if the obstacles and changes in the surface are determined to be larger compared to a mode threshold; Wherein the controller adjusts the limits and thresholds for the suspension system based on the severity of the terrain; this may include increasing compliance, vehicle height and/or wheel base, and/or decreasing the wheel's speed as the terrain becomes more sever.
14. the method of any preceding claims, wherein the controller can use sensor data to determine the profile of the surface the vehicle is on, and based on the data the controller will adjust the height of the wheels of the vehicle to match the profile of the surface.
15. the method of any preceding claims, wherein the controller can use the sensor data to determine that one or more wheels are driving over an obstacle; Wherein the controller can do at least one of raise the height and/or adjust the speed of the wheel(s) going over the obstacle, retract one or more wheels, reduce or increase the compliance of individual wheels, to reduce the impact caused to the suspension.
16. The method of any preceding claims, wherein the controller is configured to adjust the position of the wheels to improve steering following following Ackerman geometry, and/or changing the speed of the vehicle's wheel to counteract or remove the effects of slipping, such as oversteer and understeer, to improve the turning of the vehicle.
17. the method of any preceding claims, wherein the controller is configured to determine the width of a drivable surface, and in response the controller is configured to extend or retract the wheels (71) of the vehicle, to adjust the wheel base to match the width of the driveable surface.
18. The method of any proceeding claims, wherein the controller is configured to determine, via the sensor data, if the driving surface terrain is loose, such as sand, snow or mud, wherein if the terrain is loose, the controller is configured to extend or retract each of the vehicle's wheels to ensure each wheels follows a unique parallel path.
19. The method of any proceeding claims, wherein the controller is configured to determine, via the sensor data, if there are any climbable breaks in the driving surface, such as potholes, ditches or trenches, and on deterring such features the controller is configured to adjust the height of individual wheels (71) so as to drive over such features with a constant, or near constant vehicle ride height.