Lifting of wheel unit of heavy vehicle or vehicle unit using active suspension

Abstract

A computer system (600) is provided, for a heavy vehicle or vehicle unit equipped with a plurality of wheel units and an active suspension (630). The computer system includes processing circuitry (610) configured to obtain an indication (620) about a desire to lift a particular one of the wheel units of the vehicle or vehicle unit from ground; use a model (640) of the vehicle or vehicle unit to determine whether the particular wheel unit is individually liftable from ground using the active suspension without the vehicle or vehicle unit tipping over, and in response to an affirmative outcome of said determining, control (650) the active suspension to individually lift the particular wheel unit from ground. A corresponding vehicle or vehicle unit, computer-implemented method, computer program product and computer- readable storage medium are also provided.

Description

LIFTING OF WHEEL UNIT OF HEAVY VEHICLE OR VEHICLE UNIT USING ACTIVE SUSPENSIONTECHNICAL FIELD

[0001] The disclosure relates generally to the field of heavy vehicles or vehicle units having height-adjustable suspension. In particular aspects, the disclosure relates to lifting of a particular wheel unit of the vehicle or vehicle unit using the height-adjustable suspension. The disclosure can be applied to heavy-duty vehicles, such as trucks, buses, and construction equipment, among other vehicle types. Although the disclosure may be described with respect to a particular vehicle, the disclosure is not restricted to any particular vehicle.BACKGROUND

[0002] Many heavy-duty vehicles have at least four wheels that serve as contact points between the vehicle and ground. Wheels equipped with inflatable (pneumatic) tires are sometimes subject to accidental deflation, such as deflation caused by the tire being punctured by a sharp object on the ground (such as road debris), a thread of the tire being worn out and finally breaking, the wheel hitting a curb at high velocity, or similar. Driving with one or more flat (i.e. deflated) tires may compromise handling of the vehicle, as well as it may cause damage to wheel rims and other parts of the vehicle. For these reasons, driving with one or more flat tires is often not recommended, and drivers are therefore advised to slow down and eventually pull off the road in case one or more flat tires are detected.

[0003] Once coming to a halt, an often tedious process of fixing a flat tire is initiated, including e.g. to replace the deflated tire with a new tire, replace the whole wheel with another (spare) wheel, or attempting to fix the deflated tire by at least temporarily sealing any leaks (if possible). As the vehicle is heavy, fixing a deflated tire often requires the use of e.g. one or more hydraulic jacks in order to lift the damaged wheel from ground, and often in combination with power tools such as impact wrenches and similar. Attempting to repair a flat tire when parked along the road may be both stressful and complicated, and often also dangerous as passing traffic may hit the parked vehicle and / or its driver. As a consequence, requesting towing assistance in order to tow the vehicle to a workshop may sometimes be a most reasonable option.

[0004] The present disclosure aims at facilitating the handling of a flat tire- situation for a heavy vehicle.SUMMARY

[0005] According to a first aspect of the present disclosure, there is provided a computer system for a heavy vehicle or vehicle unit equipped with a plurality of wheel units and an active suspension, wherein the computer system includes processing circuitry configured to: - obtain an indication about a desire to lift a particular one of the wheel units of the vehicle or vehicle unit from ground; - use a model of the vehicle or vehicle unit to determine whether the particular wheel unit is individually liftable from ground using the active suspension without the vehicle or vehicle unit tipping over, and in response to an affirmative outcome of this determining, control the active suspension to individually lift the particular wheel unit from ground. The first aspect of the disclosure may seek to improve the handling of flat tire situations for a heavy vehicle. A technical benefit may include that instead of having to rely on equipment such as hydraulic jacks and similar, the height-adjustable suspension of the vehicle may be used instead to lift a wheel of the vehicle from ground, such that e.g. a flat tire can be replaced and / or repaired. In addition, using the height-adjustable suspension of the vehicle to lift the wheel may also, in some situations, allow the vehicle to continue travelling with the vehicle lifted from ground, such that the vehicle may drive to for example a tire repair workshop on its own and without the need for tow truck assistance. In particular, a benefit may include that by first, before any attempt to lift the particular wheel, the use of the model to first confirm that such lifting is actually possible and safe, situations in where energy is spent on unfruitful lifting attempts can be avoided, and in particular that situations wherein an attempted lifting of the particular results in harm to the vehicle due to the vehicle e.g. tipping over are avoided.

[0006] Optionally, in some examples, including in at least one preferred example, of the computer system, the particular wheel unit may be arranged on an axle of the vehicle or vehicle unit, and wherein to individually lift the particular wheel unit from ground may include to (by controlling the active suspension accordingly) not lift another wheel unit arranged on an opposite side of the same axle. A technical benefit may include that e.g. a wheel unit can thus be lifted even when the axle is not a lift axle capable of lifting all wheelsprovided on the axle simultaneously, etc., and in that lifting of only one wheel unit (or wheel units on only one side of the axle) may allow for sufficient balance provided by the other wheel units remaining in contact with ground.

[0007] Optionally, in some examples, including in at least one preferred example, of the computer system, the processing circuitry may be further configured to: obtain suspension capability information pertinent to a current capability of the active suspension, and in response to a non-affirmative outcome of this determining, use the model of the vehicle or vehicle unit to further determine whether the vehicle or vehicle unit can, in accordance with the obtained suspension capability information and by using the active suspension, be transitioned to a new state in which the particular wheel unit is liftable from ground without the vehicle or vehicle unit tipping over and, in response to an affirmative outcome of this further determining, control the active suspension to transition the vehicle or vehicle unit to the new state and lift the particular wheel unit from ground. A technical benefit may include that if the vehicle is currently in a state not suitable for lifting the particular wheel unit, the suspension capability information can be used to figure out whether the active suspension can be used to transition the vehicle into a new state in which lifting is capable, thus further enhancing the likelihood of eventually being able to lift the wheel unit.

[0008] Optionally, in some examples, including in at least one preferred example, of the computer system, transitioning the vehicle or vehicle unit to the new state may include shifting a normal load on the particular wheel unit to one or more other wheel units. A technical benefit may include that the active suspension thus allows to take weight of the particular wheel unit, such that it may be lifted without further affecting the overall vehicle or vehicle unit.

[0009] Optionally, in some examples, including in at least one preferred example, of the computer system, shifting the normal load (on the particular wheel unit) may include moving a center of gravity (COG) of the vehicle or vehicle unit using the active suspension. A technical benefit may include that the COG may e.g. be moved such that it lies within a triangle defined by e.g. two wheel units on another wheel axle and the remaining wheel unit on the same wheel axle as the particular wheel unit, thus guaranteeing a stable system that does not tip over when the particular wheel unit is lifted.

[0010] Optionally, in some examples, including in at least one preferred example, of the computer system, shifting the normal load (on the particular wheel unit) may include using astiffness of a chassis of the vehicle and a roll movement caused by the active suspension. A technical benefit may include that the normal load on the particular wheel unit may thus be e.g. reduced without necessarily changing / moving the vehicles center-of-gravity, as the stiffness of the chassis may be used to take the weight of the particular wheel unit.

[0011] Optionally, in some examples, including in at least one preferred example, of the computer system, the processing circuitry may be further configured to control the active suspension to lift the particular wheel unit from ground only after also confirming that an energy required to perform such a lifting of the particular wheel unit and / or transitioning of the vehicle or vehicle unit to the new state is below an energy threshold. A technical benefit may include that the energy threshold may for example correspond to a cost of instead calling for assistance (from e.g. a towing truck or mobile service unit), and energy may thus be saved by using such other alternatives if proven to be more energy and cost effective.

[0012] Optionally, in some examples, including in at least one preferred example, of the computer system, the suspension capability information may include at least one of: i) current normal load forces on each of a plurality of wheel units of the vehicle or vehicle unit including the particular wheel unit; ii) limitations for possible normal load forces on each of the plurality of wheel units after adjusting the active suspension; and iii) limitations for possible distances between each of the plurality of wheel units and a chassis of the vehicle or vehicle unit and / or for possible vertical displacements / heights of the wheel units. A technical benefit may include that such knowledge about the suspension may be used to avoid attempting a lift that will not be possible because of the active suspension reaching its capability limits, and thus avoid wasting energy on such attempts that are bound to fail.

[0013] Optionally, in some examples, including in at least one preferred example, of the computer system, the model of the vehicle or vehicle unit may include a mapped knowledge of a loaded vehicle or vehicle unit weight distribution and standard wheel height level positions. A technical benefit may include that such knowledge may further help to figure out how / if the active suspension can be used to take sufficient weight of the particular wheel unit to lift it from ground.

[0014] Optionally, in some examples, including in at least one preferred example, of the computer system, the model of the vehicle or vehicle unit may further include mapped knowledge about how normal loads on one or more wheel units of the vehicle depend on at least one of a roll, pitch, heave and individual wheel unit height positions of the vehicle orvehicle unit. A technical benefit may include that such knowledge may further help to decide if / how lifting of the wheel unit is possible, and e.g. what roll, pitch and / or heave of the vehicle or vehicle unit that should be requested in order to obtain a desired configuration of the vehicle or vehicle unit suitable for lifting the particular wheel unit.

[0015] Optionally, in some examples, including in at least one preferred example, of the computer system, using the model of the vehicle or vehicle unit to determine that the particular wheel unit is liftable from ground may include to: - obtain a size of a normal load force applied on the particular wheel unit as well as a total normal load force of the vehicle or vehicle unit, wherein the particular wheel unit and a first other wheel unit of the vehicle or vehicle unit are arranged on a first axle of the vehicle or vehicle unit and second and third other wheel units of the vehicle or vehicle unit are arranged on opposite sides of another, second axle of the vehicle or vehicle unit, wherein the particular wheel unit and the second other wheel unit are on a same side of the vehicle or vehicle unit, and - verify that i) the normal load force on the particular wheel unit times a distance from the particular wheel unit to a first diagonal formed between the first and second other wheel units exceeds a sum of the total normal load force times a distance from a center of gravity (COG) of the vehicle or vehicle unit to the first diagonal, and ii) the COG of the vehicle or vehicle unit is on an opposite side of the first diagonal than the particular wheel unit. A technical benefit may include that such a mathematical model may provide the answer to the question whether the particular wheel unit is liftable or not based only on knowledge about the vehicle’s or vehicle unit’s geometry and indications of normal load forces on the wheel units, which may already be available from the active suspension and similar.

[0016] Optionally, in some examples, including in at least one preferred example, of the computer system, the processing circuitry may be further configured to: - determine whether a differential of an axle to which the particular wheel unit belongs is an open differential, and, if affirmative (i.e. in response to an affirmative outcome of the determining), control a braking system of the vehicle or vehicle unit to apply brake force on the particular wheel unit proportional to a brake force applied on another wheel unit arrange on an opposite side of the same axle. A technical benefit may include that the brake force applied on the lifted wheel unit may avoid all power being distributed only to the particular wheel unit, and instead allow to route some or all power to the wheel unit on the opposite side that is still in contact with ground, to improve overall traction of the vehicle or vehicle unit.

[0017] Optionally, in some examples, including in at least one preferred example, of the computer system, the processing circuitry may be further configured to: - obtain an indication about a desire to loosen and / or tighten one or more wheel bolts or nuts of the particular unit wheel unit, and control a motion support device (MSD) of the vehicle or vehicle unit to rotate the particular wheel unit once the particular wheel unit is lifted from ground. A technical benefit may include that a tool may be used to lock a wheel bolt or nut, and when the wheel unit is rotated by the MSD, the wheel bolt or nut can be brought lose without the need for e.g. an impact wrench or similar.

[0018] Optionally, in some examples, including in at least one preferred example, of the computer system, the processing circuitry may be further configured to: -transition the vehicle or vehicle unit to a limp-home mode, in which the vehicle or vehicle unit is allowed to be driven at a limited speed and / or with a limited steering with the particular wheel unit lifted from ground. A technical benefit may include that the vehicle or vehicle unit may thus be driven to e.g. a nearby workshop in order to fix the problem giving rise to the need for lifting the particular wheel unit, such as a deflated tire or similar.

[0019] Optionally, in some examples, including in at least one preferred example, of the computer system, to control the active suspension to lift the particular wheel unit from ground may include to compensate wheel height levels of one or more other wheels of the vehicle or vehicle unit such that a normal load on the particular wheel unit is zero. A technical benefit may include that in such a situation, the particular wheel unit is unloaded and may thus be lifted without affecting the state of the vehicle or vehicle unit, i.e. without causing any partial tipping or similar.

[0020] According to a second aspect of the present disclosure, there is provided a vehicle or vehicle unit including a plurality of wheel units arranged on multiple axles of the vehicle or vehicle unit, an active suspension for controlling a distance between each wheel unit and a chassis of the vehicle or vehicle unit, and the computer system of the first aspect or any example thereof disclosed herein.

[0021] Optionally, in some examples, including in at least one preferred example, of the vehicle or vehicle unit, the vehicle or vehicle unit may have a total of two axles each having a transverse pair of wheel units. A technical benefit may include that there are more than three wheel units, and thus allowing one wheel unit to (possibly) be lifted from ground without tipping.

[0022] Optionally, in some examples, including in at least one preferred example, of the vehicle or vehicle unit, the vehicle or vehicle unit may be an articulated bus formed by at least two vehicle units, and wherein at least one of the two vehicle units may have a total of two axles each having a transverse pair of wheel units. A technical benefit may include that even if on such vehicle unit has only two wheel units in total, the wheel units on the other vehicle unit may be used to provide sufficient support to lift a wheel unit of the vehicle unit having only two wheel units.

[0023] According to a third aspect of the present disclosure, there is provided a computer- implemented method for lifting a particular wheel unit of a heavy vehicle or vehicle unit equipped with a plurality of wheel units and an active suspension. The method includes obtaining, by processing circuitry of a computer system, an indication about a desire to lift a particular wheel unit of the vehicle or vehicle unit from ground; using (by the processing circuitry) a model of the vehicle or vehicle unit to verify / determine that the particular unit is individually liftable from ground using the active suspension without the vehicle or vehicle unit tipping over, and in response to this determining, controlling (by the processing circuitry) the active suspension to individually lift the particular wheel unit from ground.

[0024] According to a fourth aspect of the present disclosure, there is provided a computer program product include program code for performing, when executed by processing circuitry of a computer system, the method of the third aspect.

[0025] According to a fifth aspect of the present disclosure, there is provided a (non- transitory) computer-readable storage medium including instructions (such as program code), which when executed by a processing circuitry of a computer system, cause the processing circuitry to perform the method of the third aspect.

[0026] The disclosed aspects, examples (including any preferred examples), and / or accompanying claims may be suitably combined with each other as would be apparent to anyone of ordinary skill in the art. Additional features and advantages are disclosed in the following description, claims, and drawings, and in part will be readily apparent therefrom to those skilled in the art or recognized by practicing the disclosure as described herein.

[0027] There are also disclosed herein computer systems, control units, code modules, computer-implemented methods, computer readable media, and computer program products associated with the above discussed technical benefits.BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Examples are described in more detail below with reference to the appended drawings, in which:

[0029] FIGS. 1A and IB schematically illustrate an exemplary heavy vehicle in form of a bus and an active suspension system provided as part of said bus, according to an example.

[0030] FIG. 2 schematically illustrates a flowchart of an exemplary method according to an example.

[0031] FIG. 3 schematically illustrates an exemplary model of a vehicle / vehicle unit according to an example.

[0032] FIGS. 4A, 4B and 4C schematically illustrate various exemplary vehicles or vehicle units according to various examples.

[0033] FIG. 5 schematically illustrates a diagram of an exemplary computer system for implementing examples disclosed herein, according to an example.

[0034] FIG. 6 schematically illustrates an exemplary computer system for implementing examples disclosed herein, according to an example.DETAILED DESCRIPTION

[0035] The detailed description set forth below provides information and examples of the disclosed technology with sufficient detail to enable those skilled in the art to practice the disclosure.

[0036] Figs. 1A and IB schematically illustrate an exemplary heavy vehicle 100 according to an example, in form of a bus. This particular vehicle 100 has a first (wheel) axle 110 and a second (wheel) axle 120. The first axle 110 includes a transverse pair of wheel units 112 and 114, and the second axle 120 includes a transverse par of wheel units 122 and 124. Herein, a “wheel unit” may be a single wheel, a set of dual wheels, a set of triple wheels, or similar. A “transverse pair of wheels” includes two wheels mounted on or arranged at opposite sides of the axle. In the particular example illustrated in Figs. 1 A and IB, the wheel units 112 and 114 of the first axle 110 are each single wheels, while the wheel units 122 and 124 of the second axle 120 are each dual wheels (i.e. a combination of two single wheels side by side). In the particular example of the vehicle 100, the first axle 110 is a steerable front axle of the vehicle 110, and the second axel 120 is a driven rear axle of the vehicle 100. Itshould be noted that herein, when referring to two wheel units being associated with, mounted on, arranged on or at, e.g., a particular “axle”, it is not necessarily so that the two wheel units are physically linked by a physical axle. For example, the steerable front axle 110 may not be a driven axle, and there may be no physical axle connecting the two wheel units 112 and 114, and similar. Thus, it is assumed that as a minimum, an axle is a representation of a pair of transverse wheel units that may or may not be physically linked / connected by a same physical axle, such as e.g. a drive shaft or similar. For example, a vehicle or vehicle unit as envisaged herein may be partially or fully electric, wherein one or more electrical machines are used instead of e.g. one or more internal combustion engines (ICEs) to propel the vehicle or vehicle unit. In such a case, there may be no axles connecting wheel units arranged on opposite sides of the vehicle, and the wheel units may instead be driven by their own individual electrical machines, or similar. The same applies for other types of propulsion systems such as hybrid-electrics, fuel cells, and similar, which are also envisaged as possible alternatives for how the vehicle or vehicle unit as envisaged herein are propelled. How exactly each wheel unit is driven or not, and e.g. whether an axle is an actual physical axle or just a representation of a transverse pair of wheel units, is not important as long as not explicitly stated to the contrary.

[0037] The vehicle 100 is equipped with an active suspension, that allows to individually control a distance between each wheel unit 110, 112, 122, 124 and a chassis of the vehicle 100 in a vertical direction. In this particular example, the active suspension includes a plurality of suspension cylinders, including a cylinder 130a for the wheel unit 112, a cylinder 130b for the wheel unit 114, two cylinders 130c for the wheel unit 122, and two cylinders 130d for the wheel unit 124. The cylinders 130a-d may be air springs (in case of a pneumatic suspension), air / hydraulic springs in case of gas-hydraulic suspension, and similar. For example, in case of a gas-hydraulic active suspension, each cylinder 130a-d may include a volume of a compressible gas (such as e.g. nitrogen) trapped between an upper part of the cylinder and a non-permeable (such as rubber) membrane. On the other side of the membrane, hydraulic fluid may be provided in order to cause actuation of the spring element in form of the compressible gas once force (from the wheel units) is exerted on the (non- compressible) hydraulic fluid. By adjusting the amount of hydraulic fluid in each cylinder, a leveling functionality may be implemented in which the distance between the vehicle chassis and each wheel unit in the vertical direction can be adjusted. There may of course also beother forms of gas-hydraulic springs, still operating on the same principle of using the movement of e.g. hydraulic fluid to compress a gas in order to provide damping.

[0038] In other examples, if the cylinders 130a-d are instead air-springs, the cylinders 130a-d may e.g. be bellows whose sizes may be adjusted depending on how much air that is currently provided in each bellow. Other examples are also envisaged, such as the cylinders 130a-d being purely hydraulic and operating based solely on hydraulic principles. Although not illustrated in Figs. 1 A and IB, one or more (steel) springs may also be provided for each wheel, in addition to the cylinders 130a-d, if required. Independent on exactly how the active suspension is constructed and operates, it is envisaged herein that the active suspension is any suspension that allows the distance between the respective wheel unit (unsprung mass) and a chassis (sprung mass) of the vehicle 100 to be adjusted. Such active suspensions are commonly known and available to the skilled person.

[0039] In order to adjust the amount of air, hydraulic fluid, etc., in each cylinder 130a-d, the active suspension includes, in this example, a plurality of fluid channels 140 in which air, hydraulic fluid, etc., can be routed to and / or from each cylinder 130a-d. The active suspension further includes at least one reservoir 142 for storing the fluid not currently in any of the cylinders 130a-d, and also a plurality of control valves 144 for controlling how the fluid flows between the cylinders 130a-d and the reservoir 142. Although not shown, the active suspension may also include one or more pressure providing elements, such as a compressor, to provide sufficient fluid pressure in the active suspension system.

[0040] The active suspension may also include one or more level sensors 146a-d, e.g. a sensor 146a at the wheel unit 112, a sensor 146b at the wheel unit 114, a sensor 146c at the wheel unit 122, and a sensor 146d at the wheel unit 124. The sensors 146a-d may be configured to provide a signal indicative of the distance between the respective wheel unit and the chassis in the vertical direction. Such signals, as well as e.g. control signals to / from the fluid valves 144, are provided via a plurality of control and / or communication lines 148 to a control unit 150. The control unit 150 may also be referred to as, or at least include, a computer system 150, and is configured to e.g. control the active suspension to individually adjust the distance between each wheel unit and the chassis of the vehicle 100.

[0041] The computer system 150 may optionally also be communicatively coupled to one or more other systems of the vehicle 100 (via e.g. the plurality of control and / or communication lines 148), for example to one or more of: a dashboard 160 of the vehicle100, such that the computing system 150 may receive signals indicative of for example a driver pressing a particular button on the dashboard, selecting a particular menu option on a touch-sensitive display of the dashboard 160, and / or to display one or more messages to the driver via the dashboard 160; a steering wheel 162 of the vehicle 100, such that the computer system 150 may receive information about e.g. a turning angle and / or turning rate of the steering wheel 162; one or more actuation pedals 164 of the vehicle 100, such as e.g. one or more of a throttle pedal, clutch pedal, brake pedal, and similar, in order for the computing system 150 to know how / when the driver presses / releases such pedals, and similar.

[0042] The computer system 150 may also be communicatively coupled to, and e.g. capable of controlling, one or more differentials 170 operating on one or more of the vehicle’s 100 (wheel axles), a steering system 172 for providing assisted (servo) steering of the vehicle 100, and / or a transmi ssion / engine system 174 of the vehicle 100 responsible for e.g. propelling and / or braking the vehicle 100. There may of course be separate systems responsible for the braking and propelling of the vehicle 100, respectively, and the computer system 150 may then of course be connected to one or both of such separate systems. In general, the control system 150 may include all required functionality in a same physical unit, or may e.g. be formed by a plurality of distributed units of the vehicle 100. For example, there may be separate units responsible for a respective part of the overall functionality, such as controlling the valves 144, reading the sensors 146a-d, and / or to perform communication / controlling one or more other parts of the vehicle 100. In any case, all such units required to perform a certain functionality being recited herein as “performed by the computer system” are then assumed to be included as part of the computer system 150.

[0043] The vehicle 100 may further include a memory 154 readable / accessible by the computer system 150. The memory 154 may be a stand-alone memory, or may e.g. form part of the computer system 150 itself. The memory 154 may store e.g. mapped knowledge related to the active suspension that the computer system 150 may access and use to control the active suspension as will be described in more detail later herein.

[0044] The vehicle 100 may further include an interface 180 through which a current capability of the active suspension can be obtained. The interface 180 may be a stand-alone interface or provided e.g. as part of the computer system 150. The interface 180 may provide suspension capability information pertinent to the current capability of the active suspension. Such information may include e.g. current normal load forces on each of the wheel units 112,114, 122 and 124; limitations for possible normal load forces on each of the wheel units 112, 114, 122 and 124 after adjusting the active suspension, and / or limitations for possible distance between each wheel unit 112, 114, 122 and 124 and the chassis of the vehicle (in the vertical direction). If not formed as part of the computer system 150, the interface 180 and computer system 150 may be communicatively connected, such that the computer system 150 may receive such information from the interface 180. The interface 180 may in turn be communicatively coupled to one or more sensors of the active suspension, such as the sensors 146a-d or other sensors (not shown) capable of providing such information about the active suspension capabilities.

[0045] The present disclosure aims at solving the problem of how to handle a situation where one of the vehicle’s 100 wheel units are damaged and need to be operated on in order to continue driving the vehicle. Such a damage may, as described earlier herein, be a damage leading to (at least partial) deflation of the wheel unit, or other damage that prevents continued use of the wheel in a safe way. To potentially avoid having to use heavy-to-handle jacks and other tools in order to remove, repair and optionally replace a damaged wheel, the present disclosure proposes to use the active suspension of the vehicle 100 to lift the damaged wheel from ground. In particular, the present disclosure proposes to, before attempting to lift the damaged wheel unit using the active suspension, using a model of the vehicle 100 to check whether it is actually possible to do so before any attempt to lift the wheel unit is made. This in order to make the procedure safer as the risk of the vehicle 100 tipping over as a result of attempting to lift a wheel unit is reduced, and also in order to save energy, as energy does not need to be wasted on lifting-attempts that are “doomed to fail” even before starting, due to a current configuration of active suspension, load and weight distribution of the vehicle, and similar.

[0046] How the computer system 150 is envisaged to operate in order to provide such lifting using the active suspension will now be described in more detail with reference also to FIG. 2.

[0047] FIG. 2 schematically illustrates a flowchart of an exemplary method 200 according to an example. The computer system 150 is envisaged as being capable of performing the various operations of the method 200.

[0048] As part of an operation S210 of the method 200, an indication is received, about a desire to lift a particular wheel unit, such as e.g. the wheel unit 122, from ground. Theindication may come from a driver (or passenger) of the vehicle 100 pressing a particular button on the dashboard 160, selecting a particular menu option on a touch-sensitive display of the dashboard 160, or similar. The indication may also, in other examples, come from another system of the vehicle 100, such as for example a driving assistance system, automated driving system, or similar, or e.g. remotely from a server, traffic planning central, or similar. The vehicle 100 may, in some examples, also be connected to a user device, such as a driver’s smartphone or similar, and the indication about the desire to lift the particular wheel unit may then come from such a user device. Other envisaged examples include e.g. to provide control buttons / levers at the vicinity of each wheel unit such that the driver may initiate the lifting of a particular wheel unit by operating the associated button / lever, and similar. In any way, exactly how the desire to lift a particular wheel unit is communicated to e.g. the computer system 150 is not relevant, as long as such a desire is in at least some way communicated to the computer system 150. In this particular example, it is assumed that the particular wheel is the wheel unit 122, and that the indication about the desire to lift the wheel unit 122 from ground is communicated to the computer system 150 from the dashboard 160 (via a communication line 148), by the driver selecting the particular wheel unit 122 from one or more options on the dashboard.

[0049] In response to receiving the indication, as part of an operation S220 of the method 200, a model of the vehicle or vehicle unit is used to determine whether the particular wheel unit 122 is liftable from ground without the vehicle 100 tipping over. As envisaged herein, “tipping over” may include an actual tipping over (or falling, overbalancing, and similar), such that the vehicle loses balance. In other examples, “tipping over” may be a sufficient deviation from a state in which the vehicle is parallel to ground, and may include e.g. the vehicle starting to tilt (but not fully tipping over) away from this parallel state. For example, it may be assumed, in some examples, that “not tipping over” means that the vehicle can remain in a state where it is parallel to ground even though one wheel unit is lifted from ground.

[0050] If it is affirmative, i.e. in response to the determining being affirmative that the particular wheel unit 122 is in fact liftable without the vehicle 100 tipping over, an operation S230 of the method 200 includes to control the active suspension to individually lift the particular wheel unit 122 from ground. Here, to “individually lift” the particular wheel unit 122 means that e.g. the other wheel unit 124 provided on the same axle 120 as the particularwheel unit 122 is not lifted from ground. Phrased differently, the envisaged computer system functionality and method 200 do not include the situation in which e.g. a wheel unit is lifted from ground as part of lifting / raising e.g. a tag or pusher axle, or some other lift axle of a vehicle.

[0051] In one example of the method 200, an optional operation S240 may be performed if it is not affirmative that the particular wheel unit 122 is liftable in the current state of the vehicle 100. The operation S240 may include to obtain capability information pertinent to a current capability of the active suspension, e.g. via the interface 180. In other examples, it is envisaged that such information can already be available and not explicitly obtained only because it was not affirmed that lifting the particular wheel unit was possible.

[0052] In an optional operation S250 of the method 200 performed in response to it being determined as part of operation S220 that the wheel unit 122 is not liftable (without the vehicle 100 tipping over) in the current state of the vehicle 100, the model of the vehicle 100 is used to further determine whether the vehicle 100 can, using the active suspension and without exceeding the current capability of the active suspension as indicated by the information obtained from e.g. the interface 180, transition the vehicle 100 into a new state in which the particular wheel unit 122 is liftable without the vehicle 100 tipping over. If yes, i.e. if it is further determined that in the new state, the wheel unit 122 is liftable without the vehicle 100 tipping over.

[0053] For example, when performing operation S220, the vehicle 100 may be in a state in which the active suspension is such that the vehicle 100 is level, e.g. in such a state that the vehicle 100 was in when previously driving and e.g. before damaging the wheel unit 122. It may then, as part of operation S220, be determined using the model of the vehicle 100 that lifting of the particular wheel unit 122 is possible in this current, level state of the vehicle 100, and the active suspension can be controlled (either directly or indirectly by the computer system 150) to lift the particular wheel unit 122 from ground. In other examples, it may instead be such that it is determined that if lifting the particular wheel unit 122 in the current state of the vehicle 100, the vehicle 100 is certain or likely to tip over. In this case, the model may be used to investigate if it is possible to shift the weight of the vehicle 100 to one or more of the other wheel units 112, 114 and 124 such that the particular wheel unit 122 can be lifted without the vehicle tipping over, i.e. that the vehicle 100 can be transitioned to a new state by performing such weight shifting, and wherein the capability of the active suspensionis taken into account when determining what is actually possible or not. The new state of the vehicle 100 may for example include that the distances between the other wheel units and the chassis of the vehicle 100 are compensated such that a normal load force on the particular wheel unit is reduced to zero, such that the particular wheel unit can then be lifted without affecting the other wheel units of the vehicle 100.

[0054] In an optional operation S260 of the method 200 after, in parallel with or even before operation S250, it may also be determined whether an energy that would be required to lift the particular wheel unit 122 and / or to transition the vehicle 100 to the new state is below (e.g. not reach) a (predetermined) energy threshold value. If affirmative, the method 200 may proceed to an operation S270 in which the vehicle 100 is transitioned into the new state by use of the active suspension. If the operation S260 is not included, the method 200 may include proceeding directly to operation S270 in response to it being confirmed as part of operation S250 that the particular wheel 122 is liftable as soon as the vehicle 100 is transitioned to the new state.

[0055] After the vehicle 100 has been transitioned to the new state as part of operation S270, the method 200 may proceed to operation S230 to lift the particular wheel unit 122 from ground.

[0056] If it is not affirmative that transitioning the vehicle 100 to a new state would make the particular wheel unit 122 liftable without the vehicle 100 risking to tip over, the method 200 may instead proceed to an operation S280, which may include to e.g. alert the driver about the particular wheel 122 not being liftable, and to provide e.g. a recommendation to call for assistance instead (from e.g. a tow truck or similar).

[0057] Also, or in addition, if it is not affirmative that the energy required to lift the particular wheel unit 122, and / or to transition the vehicle 100 to the new state, is below the energy threshold value, the operation S280 may also be performed, and include to notify the driver that it may be possible to lift the particular wheel unit 122 and / or to transition the vehicle 100 to the new state, but that it may be more energy efficient to instead call for assistance and e.g. await the arrival of a tow truck or similar.

[0058] For example, in some examples, transitioning the vehicle 100 to the new state may include changing normal loads on one or more other wheel units arranged on one or more other axles of the vehicle 100, such as the wheel units 112 and 114 arranged on the other axle 110, and / or on the wheel unit 124 arranged on (the opposite side of) the same axle 120.

[0059] For example, in some examples, changing the normal loads may include moving a center-of-gravity (COG) of the vehicle 100 using the active suspension. In other examples, either in addition to or instead of moving the COG, a stiffness of the vehicle’s 100 chassis can be used to change the normal loads on the wheel units. For example, a rolling maneuver / motion may be initiated by lowering a wheel unit on one side of an axle and raising a wheel unit on another, opposite side of the same axle. The chassis stiffness may then be used to translate this rolling maneuver into a changing of normal loads on one or more wheel units on another axle of the vehicle 100, and similar.

[0060] After having lifted, or in combination with lifting, the particular wheel unit 122 as part of operation S230, the method 200 may optionally include an additional operation 290 in which the vehicle 100 is transitioned to a limp-home state / mode, in which the vehicle 100 is allowed to continue driving with the particular wheel 122 lifted from ground. This may e.g. be beneficial in that the driver can then drive the vehicle 100 to a nearby (tire) repair shop or other workshop instead of e.g. attempting to (fully) fix the particular wheel unit 122 on his / her own behalf when parked along the road, and / or to fix any other underlying cause of the particular wheel unit 122 not being usable. For example, such a limp-home mode of the vehicle 100 may include to reduce / limit a maximum allowed steering (such as a maximum allowed steering angle and / or steering angle rate shift), in order to reduce or eliminate a risk of the vehicle 100 tipping over due to not having all of the wheel units 112, 114, 122 and 124 in contact with ground while driving, e.g. in order to allow dynamic vertical roll transfer in order not to jeopardize for example a three-point surface balance caused by the lifted particular wheel unit 122. Phrased differently, reducing / limiting the steering may help to reduce or eliminate the additional risks caused by a reduced balance of the vehicle 100 due to lifting the particular wheel unit 122, e.g. by using a pre-tested limp-home speed and lateral acceleration limits for the steering for one or more pre-approved loading conditions during the limp-home mode. In other examples, such a limp-home mode may also, or instead, include to reduce / limit a maximum allowed speed of the vehicle 100, or similar, to also reduce or eliminate the various risk arising from having one less wheel unit in contact with ground due to the lifting of the particular wheel unit 122.

[0061] Herein, it is further envisaged that in some examples, one or more sensors may be provided in order to automatically detect that a particular wheel unit (such as 122) is damaged. Such sensors may include e.g. wheel speed sensors, tire pressure sensors (TPMS),accelerometers, etc. In some examples, the detection of a desire to lift a particular wheel unit may cause a warning to be issued to the driver, and e.g. a provision of options of e.g. attempting to lift the wheel unit in order to perform repair, an option to e.g. enter the limphome mode, or e.g. a message indicating that such modes can be entered but that it would be more energy efficient to instead call for assistance and await the arrival of a tow truck, mobile service unit, or similar. In other examples, it may be determined that e.g. a limp-home mode should automatically be activated if it is detected that a particular wheel unit is damaged and that the wheel unit is liftable from ground without the vehicle tipping over, and e.g. that the vehicle may be driven with the particular wheel unit lifted from ground, perhaps at limited steering, acceleration, speed, etc.

[0062] Optionally, after having lifted the particular wheel 122 as part of operation S230, the method 200 may as part of an operation S292 include to control a motion support device (MSD) of the vehicle, e.g. as part of the transmission / propulsion 174, rotate the particular wheel unit 122 once it has been lifted from ground. This may be used to e.g. open and / or close wheel bolts of the particular wheel unit 122, and thereby reduce or eliminate the need for one or more power tools such as an impact wrench or similar. For example, the driver may be provided with a simple tool that attaches between a wheel bolt and ground (or between a wheel bolt and some part of the vehicle 100 other than the particular wheel unit 122), such that when the particular wheel unit 122 is rotated, the wheel bolt is either opened or closed depending on the rotation direction of the particular wheel unit 122. Controlling the MSD to rotate the particular wheel unit 122 may e.g. be performed in response to first having obtained an indication that such a rotation is desired, e.g. by the driver operating a suitable switch, lever or similar alternative on the dashboard 160, or similar. An electric MSD may be particularly useful for rotating an individual wheel unit. If the wheel units are powered by e.g. an internal combustion engine (ICE) or similar, it is envisaged that rotation of a single wheel unit may still be provided by proper configuration of e.g. differentials and brake forces applied to the other wheels, at least in some situations.

[0063] Optionally, after having lifted, or in combination with lifting, the particular wheel unit 122, the method 200 may, in an operation S294, include to determine whether a differential of the axle 120 to which the particular wheel unit belongs is equipped with a differential, such as the differential 170. If affirmative, and in response to further confirming that the differential is an open differential, the operation S294 may further include to controla brake force applied to the particular wheel unit 122 such that the applied brake force is e.g. proportional to a brake force applied on the other wheel unit 124 on the opposite side of the axle 120. This may help to avoid all transmission force / torque being applied only to the lifted wheel unit 122 due to the resistance of turning this wheel unit 122 being lower due to being lifted. Instead, more or all (if the particular wheel unit 122 is fully braked) of the propulsion torque can be provided instead to the other wheel unit 124.

[0064] With reference also to FIG. 3, one example of a model of a vehicle and how to determine whether a particular wheel unit is liftable without the vehicle tipping over will now be described in more detail. As used herein, a model of a vehicle (or vehicle unit) may e.g. be a static, dynamic and / or kinematic model of the vehicle or vehicle unit.

[0065] FIG. 3 schematically illustrates an exemplar arrangement of wheel units of a vehicle 300 according to an example. The vehicle 300 has four wheel units 312, 314, 322 and 324, wherein the wheel units 312 and 314 are considered to belong to a first axle 310 of the vehicle 300 and the wheel units 322 and 324 are considered to belong to a second axle 320 of the vehicle 300. For example, the vehicle 300 may correspond to the vehicle 100, if assuming that the wheel units 122 and 124 of the vehicle 100 are single wheel units instead of dual wheel units, and vice versa.

[0066] In this example, it is further assumed that a spacing T between the wheel units 312 and 314 is the same as a spacing between the wheel units 322 and 324. The spacing T is measured between corresponding center points w1, w2, w3and w4of the wheel units 312, 314, 322 and 324, respectively, and may also be referred to as a track width of the vehicle 300 or similar.

[0067] In this example, it is further assumed that a spacing between the two wheel axles 310 and 320 is L, and measured between e.g. the center points uq and w3(or e.g. between w2and w4). The spacing L may also be referred to as a wheelbase of the vehicle 300 or similar.

[0068] A first diagonal d14is formed between the two diagonally opposite wheel units 312 and 324, and a second diagonal d24is formed between the two diagonally opposite wheel units 314 and 322, as indicated in FIG. 3.

[0069] The vehicle 300 further has a longitudinal centerline 11 located in the middle of, i.e. at a distance T / 2 to each of, the center points w and w2(or the center points w3and w4). The vehicle 300 also has a transverse centerline l2located in the middle of the two axles 310 and 320, i.e. at a distance L / 2 from each of the axles 310 and 320. In this example, a center Cof the vehicle is assumed to lie at an intersection of the centerlines l and l2, e.g. at a distance L / 2 from each of the respective axles 310 and 320, and a distance T / 2 from each of the respective longitudinal sides of the vehicle (measured e.g. as a distance from the center point w to , as indicated in FIG. 3.

[0070] In this example, it is further assumed that a normal load FZ1is present on the wheel unit 310, a normal load (i.e. force) FZ2is present on the wheel unit 312, a normal load FZ3is present on the wheel unit 322, and that a normal load FZ4is present on the wheel unit 324. Here, a “normal load (force)” is a force appearing on a wheel unit due to a loading of the vehicle 300, including e.g. a weight of the vehicle 300 on its own as well as that of any cargo, driver, passengers, fuel, etc., that the vehicle is currently carrying. The forces FZ1 Z4are, as indicated in FIG. 3, oriented along the vertical (e.g. z-) direction, and pointing vertically towards ground (if assumed that FIG. 3 illustrates the vehicle 300 as seen from above).

[0071] Using the model of the vehicle 300 illustrated in FIG. 3, it can be deduced that in order to e.g. lift the wheel unit 312 without the vehicle 300 tipping over, a total normal load (force) Fztotai= FZ1+ FZ2+ FZ3+ FZ4times a distance q of a center-of-gravity COG of the vehicle 300 should not be less than the force FZ1times a distance Fxbetween the center point of the wheel unit 312 and the diagonal d23formed between the other wheel unit 314 on the same axle as the wheel unit 312 and the wheel unit 322 of the other axle. Phrased differently, for the wheel unit 312 to be liftable from ground, the following condition should be satisfied:Fztotai ’ Q — FZ1’ Ri-A more strict condition may be satisfied as Fztotai• q > FZ1• Rt. Here, it is also further assumed that if the COG lies on a same side of the diagonal d23as the center pointthe distance q will be negative, and the condition not fulfilled.Likewise, for the other wheel units 314, 322 and 324, similar conditions may be deduced in order for each of these wheel units to be liftable from ground without the vehicle 300 tipping over, namely thatfor the wheel unit 314,Fztotai ’rFZ3• R3for the wheel unit 322, andFztotai ’ Q — FZ4 ’ ^4for the wheel unit 324 (or with > instead of > for stricter conditions), wherein r is a distance from the COG to the diagonal d14, and wherein R2and R3are the distances from the center points w2and w3, respectively, to the diagonal d14, and wherein / ?4is the distance from the center point w4to the diagonal d23, as indicated in FIG. 3. Phrased differently, in order to lift a particular wheel unit on a particular axis, the total normal load (force) times a distance to a diagonal formed between the other wheel unit on the particular and the diagonally opposite wheel unit on the other axis should preferably exceed the normal load (force) on the particular wheel unit times a distance between the particular wheel unit and the same diagonal.

[0072] FIG. 3 thus serves to illustrate an example of how a model of the vehicle can be used to determine whether a particular wheel unit is liftable, based on knowledge about e.g. the various geometries of the vehicle and at least a normal load (force) on the particular wheel unit and a total normal load (force) of the vehicle (or vehicle unit) as a whole. For example, real-time data may be obtained from various sensors (such as pressure sensors or other forms of load sensing) provided at each wheel or wheel unit.

[0073] If a current state of the vehicle 300, i.e. current normal load forcesZ1 Z4are such that it is confirmed that e.g. the particular wheel unit 322 can not be safely lifted from ground, the model shown in FIG. 3 may further be used to deduce whether the normal load forcesZ1 Z4can be changed such that the relevant condition is fulfilled, i.e. whether the vehicle 300 can be transitioned into a new state (i.e. a new normal load forces configuration) in which the condition is fulfilled and the particular wheel unit is liftable from ground without the vehicle tipping over. In order to do so, it is envisaged as being useful to consider the current capability of the active suspension, such that only e.g. candidate normal load forces for the various wheel units are tested that are actually achievable by the active suspension.

[0074] FIG. 3 also illustrates an example of how the distances r, q and / ?i,...,4can be calculated based on knowledge about the vehicle’s 300 geometry.

[0075] For example, a distance x of the COG to the longitudinal centerlinecan be found aswhere FZright= FZ2+ FZ4assuming the COG is currently on the right side of the longitudinal centerline Zxas shown in FIG. 3. The same expression for x may still apply also with the COG of the vehicle being on the left side of the longitudinal centerline l2, in which case the value of x would be negative. Similarly, a distance y of the COG to the transverse centerline l2can be found aswhere FZrear= FZ3+ FZ4assuming the COG is currently below the transverse centerline l2as shown in FIG. 3. The same expression for y may still apply also with the COG of the vehicle being above the transverse centerline l2, in which case the value of y would be negative. Using the center point w4as an example, an angle 6 between the diagonal cZ14and the longitudinal centerline Zxcan be defined as 6 = atan(T / 2). The perpendicular distance Z?4from center point w4to the diagonal d23can be defined asand similar expressions may be found also for the other distances RltR2and R3, etc.

[0076] A shortest distance h from the COG to the vehicle center c can be defined as h = / x2+ y2, and an angle < > between a line extending from the vehicle center c to the COG and the diagonal cZ14can be defined as (p = asin(x / / i) — 6. From these expressions, one can finally find that r = h • sin (p and q = h • sin(7T — 20 — < >).

[0077] A model of the vehicle 100 as presented above may form part of mapped knowledge about the vehicle. Such mapped knowledge may indicate an estimated dynamic response of the vehicle, and may further include e.g. how normal loads on the wheel units depend on e.g. at least one of a roll, pitch, heave and individual wheel unit height positions (i.e. distances between wheel unit and chassis), and about a loaded vehicle weight distribution and standard wheel level height positions (i.e. distances between wheel unit and chassis when the vehicle is level). Such knowledge may be collected offline, e.g. in a laboratory or during previous driving experiences. Knowledge may be collected about how e.g. normal load forcesFzidepend on distances dzi, how distances dzidepend on normal load forces Fzi, and / or e.g. how normal load forces Fzidepend on a vehicle roll angle, pitch angle, heave and / or COG. Here, distances dzimay e.g. be defined as distances between wheel unit and chassis, distances between chassis and ground at each wheel unit, deviations from a level ride height of the vehicle 100, etc., or in any other way suitable to quantify whether a particular wheel unit is lifted and by how much. If e.g. defining the distances as deviations from some level (such as a ride height level), the distances may of course also be negative, to indicate that for example a particular wheel unit is lowered instead of lifted, etc. Such distances may also be referred to as e.g. vertical wheel unit displacements, or similar. Phrased differently, mapped knowledge about the vehicle 100 may e.g. include one or more equations such as presented above, and / or tabulated data obtained from experiments and / or real driving experiences. In case of tabulated data, it is envisaged that such data may also be interpolated and / or extrapolated, or otherwise combined, in order to provide estimates for situations that do not directly correspond to any set of data stored as part of the mapped knowledge. Mapped knowledge, such as tabulated data, may e.g. be stored in the memory 152 and access by the computing system 150 as part of performing the envisaged method and operations herein.

[0078] As an example, experiments were performed on a bus having four wheel units distributed evenly on two axles. A total normal load of the bus was determined to be 13195 kilograms [kg]. When level (as a baseline), the normal load on each wheel unit was determined to be 2740 kg on the front left wheel unit, 2215 kg on the front right wheel unit, and 4120 kg on each of the rear left and right wheel units. In an attempt to lift the front right wheel unit from ground, it was determined that the comer of the front left wheel unit should be lifted 40 mm, that the corner of the front right wheel unit should be lowered 30 mm, and that height of the rear wheel units should be left unchanged. Lowering a comer was performed by retracting (i.e. by cylinder compression) the corresponding wheel unit, and lifting a comer was performed by lowering the corresponding wheel unit (i.e. by cylinder extension). After performing the determined operations as indicated above, it was further determined that the new state (i.e. the new normal loads configuration) was that a normal load on the front left wheel unit was 4820 kg, that a normal load on the front right wheel unit was 0 kg, that a normal load on the rear left wheel unit was 1680 kg, and that a normal load on the rear right wheel unit was 6620 kg, summing up to a total normal load of the vehicle of 13120kg. Normal loads were determined using scales positioned between each wheel unitand ground. The difference in total normal load force before and after transitioning the vehicle to the new state was attributed to a person being present in the vehicle when establishing the baseline but not during the attempted wheel unit lift. More importantly, it was noted that by transitioning the vehicle to the new state, the normal load on the front right wheel unit was indeed reduced to 0 kg, and the front right wheel unit could then be lifted without affecting the other wheel units and with no risk of the vehicle tipping over.

[0079] Various other exemplary vehicles or vehicle units as envisaged herein will now be described with reference also to FIGS. 4A, 4B and 4C.

[0080] FIG. 4A schematically illustrates a semitrailer vehicle combination 400, including a tractor vehicle A and a semitrailer B. For the present disclosure, all of the combination 400 may be referred to as a vehicle, or the parts A and B may be referred to as respective vehicle units of the combination 400. For the present disclosure, the reference numeral 400 may also be used to denote only the tractor vehicle A, etc. In what follows, the reference numeral 400 refers also to the tractor vehicle A.

[0081] The vehicle 400 includes a first axle 410 (a steerable front axle, in this example) and a rear axle 420 (a driven axle, in this example). A (single) wheel unit 412 is provided on one side of the axle 410 (with another, not shown, such wheel unit also being provided on the other side of the axle 410). A (dual) wheel unit 422 is provided on one side of the axle 420 (with another, now shown, such wheel unit also being provided on the other side of the axle 420). The vehicle 400 further includes a computer system (control unit) 450, which may correspond to the computer system 150 described earlier herein with reference to e.g. FIGS. 1 A and IB. The particular wheel unit that is to be lifted (if affirmed by the method / computer system 450) may e.g. be the wheel unit 412, the wheel unit 422, or any other wheel unit on the axles 410 and 420. It is thus envisaged that the vehicle 400 further includes an active suspension, in order to individually control the vertical heights / displacements of the wheel units, following the same principles as already discussed herein.

[0082] FIG. 4B schematically illustrates another exemplary vehicle 401 in form of an articulated bus. In this case, the vehicle 401 has two vehicle units A and B, namely a front unit A and a rear unit B. The rear unit B is linked to the front unit A using an articulation, in order to e.g. increase the tumability of the rather long vehicle 401 as a whole. The front unit A includes two axles, namely a front (steerable) axle 410a and a rear axle 420a / 410b. The rear unit B includes a single axle 420b, which is preferably a driven axle of the vehicle 400.A wheel unit 412a is provided on the axle 410a (with a similar wheel unit also provided on the other, not shown, side of the axle 410a). A wheel unit 422a / 412b is provided on the axle 420a / 412b (with a similar wheel unit also provided on the other, not shown, side of the axle 420a / 412b. A wheel unit 422b is provided on the axle 420b (with a similar wheel unit also provided on the other, not shown, side of the axle 420b). The vehicle 401 has an active suspension for individual controlling the vertical heights / displacements of the wheel units, as well as a computer system (control unit) 450, that may e.g. correspond to the computer system 150.

[0083] In some examples, the procedure for lifting a particular wheel unit of a vehicle or vehicle unit may apply to e.g. the axle 410a and the axle 420a, and the particular wheel unit may be any of the wheel units 412a and 422a (or their counterparts on the other side of the unit B). In this case, the vehicle unit B has four wheel units on two axles. When performing the determination regarding whether such a particular wheel unit is liftable without the vehicle 401 tipping over, the read vehicle unit B may either be ignored or taken into account, e.g. with a model of the vehicle 401 that takes the geometry of the whole vehicle 401 into account. In some other examples, the procedure for lifting the particular wheel unit of a vehicle or vehicle unit may apply to e.g. the axle 410b and the axle 420b, such that the vehicle units that may or may not (determine on the outcome of the procedure) be lifted correspond to vehicle units 412b and 422b (and their counterparts on the other side of the unit B), etc. In such a situation, the front unit A may be ignored when performing the required calculations before (possibly) attempting to lift a wheel unit, or may be taken into account if the model of the vehicle 401 is such that the geometry of the full vehicle 401 is included. It may, in yet other examples, also be envisaged that e.g. if attempting assess the liftability of a wheel unit on the axle 420a / 410b, it may be considered whether sufficient balance of the vehicle 401 may be obtainable by adjusting the normal loads on the other wheel units, including both those on the axle 410a and the axle 420b. In this case, the risk may not necessarily include the vehicle 401 “tipping” over, but rather e.g. a sagging of the vehicle on the middle, a damaging twist of the vehicle 401 at the articulation, or similar. This applies to all examples herein, i.e. that “tipping over” is used as a term for all unwanted situations, such as part of the vehicle hitting the ground due to lifting of the particular wheel unit, the vehicle falling over on its side, etc., which may be caused by a change of balance (or loss of balance) caused by lifting of the particular wheel unit.

[0084] FIG. 4C describes yet another exemplary vehicle 402 in the form of a delivery truck. Here, there is no vehicle units. The vehicle 402 has a front (steerable) axle 410a / 410b, and two rear axles 420a and 420b (that may or may not both be driven axles). A wheel unit 412a / b is provided on the axle 410a / 410b (and similarly on the other side of the vehicle 402), a wheel unit 422a is provided on the axle 420a (and similarly on the other side of the vehicle 402), and a wheel unit 422b is provided on the axle 420b (and similarly on the other side of the vehicle 402). The vehicle 402 has an active suspension, that is capable of individually adjusting the vertical heights / displacement of the wheel units on the axle 410a / 410b, as well of the wheel units on at least one of the axles 420a and 420b. The vehicle 402 further includes a computer system (control unit) 450, that may correspond to the computer system 150. It is further assumed that e.g. one of the axles 420a and 420b is a lift axle that may be raised. In other examples, it may be assumed that if none of the axles 420a and 420b are liftable axles, or in a situation wherein both of the axles 420a and 420b are lowered when the procedure of the present disclosure is to be performed, the axles 420a and 420b may be considered as a same “axle”, and the wheel units on each side of the vehicle 402 that belong to either the axle 420a or the axle 420b may be considered as a same “wheel unit”, or similar. In other such cases, only a single one of the axles 420a and 420b may be considered in combination with the axle 410a / 410b, etc.

[0085] In some examples, the procedure of the present disclosure may apply when one of the axles 420a and 420b is lifted, in which case the vehicle 402, for the purpose of the present disclosure, is a vehicle with only a front axle and a rear axle. For example, if the axle 420b is lifted, the front axle 410a and the rear axle 420a may be considered as the two axles in e.g. FIG. 3. Likewise, if it is instead the axle 420a that is lifted, the front axle 410b and the rear axle 420b may be considered as the two axles in e.g. FIG. 3. Generally herein, it is envisaged that even though a vehicle or vehicle unit may have two or more axles arranged closely together such that balance is not a real issue if attempting to lift a wheel unit of one of those axles (as support would always be provided by the wheel units of the other closely arranged axle), the principles discussed herein still apply, as one of the closely arranged axles may e.g. be lifted, the two or more closely arranged axles may be considered as a same “axle” as mentioned above, or only a single one of the two or more closely arranged axles may be considered in combination with e.g. a front axle that is separated from the two or more closely arranged axles. Phrased differently, the present disclosure is not related to whether aparticular wheel unit on one of multiple closely arranged axles is liftable, as it is envisaged that sufficient support / balance is always provided by the one or more other closely arranged axles than the one on which the particular wheel unit is provided. Instead, the present disclosure is concerned with determining whether a particular wheel is liftable, where lifting of the particular wheel would risk causing sufficient unbalance for the vehicle to “tip over” (as defined above, including e.g. any undesired risk of damage to the vehicle, and e.g. sagging, leaning, heaving, etc., of the vehicle). As an example, if considering a vehicle with a front axle and two rear axles, the present disclosure is relevant if attempting to decide whether to lift a wheel unit on the front axle, in case which the two rear axles may either be considered as a same “axle”, or one of the rear axles may be ignored. The present disclosure is, for such a vehicle, also relevant if attempting to decide whether to lift a wheel unit on the rear axle, in case the other rear axle is for example already lifted, or similar. The present disclosure may also apply e.g. if attempting to decide whether wheel units of both the rear axles (on a same side of the vehicle) are liftable together, or similar, as that may also risk causing the undesired jeopardizing of the three-point balance introduced by lifting one particular wheel unit (or wheel unit combination on a same side of the vehicle) that would, if not lifted, provide the fourth point of contact with ground.

[0086] FIG. 5 schematically illustrates a diagram of an exemplary computer system 150 for implementing examples disclosed herein. The computer system 500 is adapted to execute instructions from a computer-readable medium to perform these and / or any of the functions or processing described herein. The computer system 500 may be connected (e.g., networked) to other machines in a LAN (Local Area Network), LIN (Local Interconnect Network), automotive network communication protocol (e.g., FlexRay), an intranet, an extranet, or the Internet. While only a single device is illustrated, the computer system 500 may include any collection of devices that individually or jointly execute a set (or multiple sets) of instructions to perform any one or more of the methodologies discussed herein. Accordingly, any reference in the disclosure and / or claims to a computer system, computing system, computer device, computing device, control system, control unit, electronic control unit (ECU), processor device, processing circuitry, etc., includes reference to one or more such devices to individually or jointly execute a set (or multiple sets) of instructions to perform any one or more of the methodologies discussed herein. For example, control system may include a single control unit or a plurality of control units connected or otherwise communicativelycoupled to each other, such that any performed function may be distributed between the control units as desired. Further, such devices may communicate with each other or other devices by various system architectures, such as directly or via a Controller Area Network (CAN) bus, etc.

[0087] The computer system 500 may comprise at least one computing device or electronic device capable of including firmware, hardware, and / or executing software instructions to implement the functionality described herein. The computer system 500 may include processing circuitry 502 (e.g., processing circuitry including one or more processor devices or control units), a memory 504, and a system bus 506. The computer system 500 may include at least one computing device having the processing circuitry 502. The system bus 506 provides an interface for system components including, but not limited to, the memory 504 and the processing circuitry 502. The processing circuitry 502 may include any number of hardware components for conducting data or signal processing or for executing computer code stored in memory 504. The processing circuitry 502 may, for example, include a general-purpose processor, an application specific processor, a Digital Signal Processor (DSP), an Application Specific Integrated Circuit (ASIC), a Field Programmable Gate Array (FPGA), a circuit containing processing components, a group of distributed processing components, a group of distributed computers configured for processing, or other programmable logic device, discrete gate or transistor logic, discrete hardware components, or any combination thereof designed to perform the functions described herein. The processing circuitry 502 may further include computer executable code that controls operation of the programmable device.

[0088] The system bus 506 may be any of several types of bus structures that may further interconnect to a memory bus (with or without a memory controller), a peripheral bus, and / or a local bus using any of a variety of bus architectures. The memory 504 may be one or more devices for storing data and / or computer code for completing or facilitating methods described herein. The memory 504 may include database components, object code components, script components, or other types of information structure for supporting the various activities herein. Any distributed or local memory device may be utilized with the systems and methods of this description. The memory 504 may be communicably connected to the processing circuitry 502 (e.g., via a circuit or any other wired, wireless, or network connection) and may include computer code for executing one or more processes describedherein. The memory 504 may include non-volatile memory 508 (e.g., read-only memory (ROM), erasable programmable read-only memory (EPROM), electrically erasable programmable read-only memory (EEPROM), etc.), and volatile memory 510 (e.g., randomaccess memory (RAM)), or any other medium which can be used to carry or store desired program code in the form of machine-executable instructions or data structures and which can be accessed by a computer or other machine with processing circuitry 502. A basic input / output system (BIOS) 512 may be stored in the non-volatile memory 508 and can include the basic routines that help to transfer information between elements within the computer system 500.

[0089] The computer system 500 may further include or be coupled to a non-transitory computer-readable storage medium such as the storage device 514, which may comprise, for example, an internal or external hard disk drive (HDD) (e.g., enhanced integrated drive electronics (EIDE) or serial advanced technology attachment (SATA)), HDD (e.g., EIDE or SATA) for storage, flash memory, or the like. The storage device 514 and other drives associated with computer-readable media and computer-usable media may provide nonvolatile storage of data, data structures, computer-executable instructions, and the like.

[0090] Computer-code which is hard or soft coded may be provided in the form of one or more modules. The module(s) can be implemented as software and / or hard-coded in circuitry to implement the functionality described herein in whole or in part. The modules may be stored in the storage device 514 and / or in the volatile memory 510, which may include an operating system 516 and / or one or more program modules 518. All or a portion of the examples disclosed herein may be implemented as a computer program 520 stored on a transitory or non-transitory computer-usable or computer-readable storage medium (e.g., single medium or multiple media), such as the storage device 514, which includes complex programming instructions (e.g., complex computer-readable program code) to cause the processing circuitry 502 to carry out actions described herein. Thus, the computer-readable program code of the computer program 520 can comprise software instructions for implementing the functionality of the examples described herein when executed by the processing circuitry 502. In some examples, the storage device 514 may be a computer program product (e.g., readable storage medium) storing the computer program 520 thereon, where at least a portion of a computer program 520 may be loadable (e.g., into a processor) for implementing the functionality of the examples described herein when executed by theprocessing circuitry 502. The processing circuitry 502 may serve as a controller or control system for the computer system 500 that is to implement the functionality described herein.

[0091] The computer system 500 may include an input device interface 522 configured to receive input and selections to be communicated to the computer system 500 when executing instructions, such as from a keyboard, mouse, touch-sensitive surface, etc. Such input devices may be connected to the processing circuitry 502 through the input device interface 522 coupled to the system bus 506 but can be connected through other interfaces, such as a parallel port, an Institute of Electrical and Electronic Engineers (IEEE) 1394 serial port, a Universal Serial Bus (USB) port, an IR interface, and the like. The computer system 500 may include an output device interface 524 configured to forward output, such as to a display, a video display unit (e.g., a liquid crystal display (LCD) or a cathode ray tube (CRT)). The computer system 500 may include a communications interface 526 suitable for communicating with a network as appropriate or desired.

[0092] The operational actions described in any of the exemplary aspects herein are described to provide examples and discussion. The actions may be performed by hardware components, may be embodied in machine-executable instructions to cause a processor to perform the actions, or may be performed by a combination of hardware and software. Although a specific order of method actions may be shown or described, the order of the actions may differ. In addition, two or more actions may be performed concurrently or with partial concurrence.

[0093] Finally, a generalized computer system falling with the present disclosure will now be described with reference also to FIG. 6.

[0094] FIG. 6 schematically illustrates an exemplary computer system 600 (that may correspond to e.g. the computer system 150 or computer system 450 as described earlier herein). The computer system 600 includes processing circuitry 610, that is configured to obtain an indication (via a message / reading / signal / detection, etc., 620 about a desire to lift a particular wheel unit of a vehicle or vehicle unit with which the computer system 600 is associated. Here, “associated” means that the computer system may e.g. form part of the vehicle or vehicle unit, or e.g. be provided separately from the vehicle or vehicle unit but still able to control the required functionality of the vehicle or vehicle unit. The computer system 600 may e.g. form part of a cloud service, server, or similar, with which the vehicle or vehicleunit is configured to communicate. It is assumed that the vehicle or vehicle unit has an active suspension 630 as described earlier herein, such as e.g. with reference to FIGS. 1 A and IB.

[0095] The computer system 600 and processing circuitry 610 are further configured to use a model 640 of the vehicle or vehicle unit to determine whether the particular wheel unit is individually liftable (that is, without also lifting e.g. a wheel unit on an opposite side of a same axle, such as done if e.g. lifting a whole axle) from ground using the active suspension 630, without the vehicle (risking) tipping over. The model 640 may e.g. be stored in and accessible from a memory 642, in form of e.g. mapped knowledge. In response to determining that the particular wheel unit is in fact liftable, the computer system 600 and processing circuitry 610 are further configured to control the active suspension 630 to individually lift the particular wheel unit from ground, via e.g. a control message / signal / indication 650 provided from the computer system 600 to the active suspension 630. Such control may e.g. be direct, or indirect if the computer system 600 e.g. instructs another unit / entity responsible for controlling the active suspension 630 to control the active suspension 630 to lift the particular wheel unit.

[0096] As illustrated in FIG. 6, optionally, the control system 600 and processing circuitry 610 may also be configured to communicate with an interface 680 from which suspension capability information (as described earlier herein, as part of e.g. a signal / message / indication 682) can be provided to the control system 600 and processing circuitry 610, such that the processing circuitry 610 may take the current capabilities of the active suspension 630 into account when deciding e.g. if the vehicle or vehicle unit can be transitioned to a new state in which the particular wheel unit is in fact liftable, as also described earlier herein. In some examples, it is envisaged that the interface 680 may, in addition to providing suspension capabilities, also receive control commands for the active suspension 630, in which case the computer system 600 and processing circuitry 610 may instead (or in addition) control the active suspension 630 via the interface 680 (in which case the messaging / signaling / indicating 682 is two-way). For example, the interface 680 may provide a standardized interface with a standardized set of possible control commands as well as e.g. a standardized set of interface capabilities that are reported from the interface 680 to the computer system 600 and processing circuitry 610. This may be advantageous in that the computer system 600 may not need to know the exact configuration of the active suspension630, as the interface 680 will serve as a translator between active suspension 630 specificdetails to a standardized language that the computer system 600 may understand.

[0097] In summary of all of the above, the present disclosure improves upon currently available technology in that it uses an active suspension of a vehicle (or vehicle unit) to lift a particular wheel unit. In particular, the present disclosure proposes to not just attempt to lift the particular wheel unit on a trial-and-error basis, but instead use a model of the vehicle to first determine whether the particular wheel unit is liftable at all. This avoids e.g. spending energy on failed lifting attempts, and / or risking that the vehicle tips over as a result of lifting the particular wheel without first checking whether the lifting is possible and safe. The present disclosure also envisages that, in some examples, the model of the vehicle is also used to check whether the vehicle may be transitioned, using the active suspension, into a new state in which the particular wheel is liftable, and to, if affirmative, transition the vehicle to this new state before attempting to lift the particular wheel.

[0098] In further summary, with the solution as proposed herein, the need for having to use heavy and often hard-to-use hydraulic jacks and similar can be avoided, making the job of the driver easier when attempting to e.g. fix a deflated tire when parked along the road. The present disclosure also proposes to, in some examples, enable the vehicle to drive in a limp-home mode after the particular wheel unit has been lifted, perhaps with a reduced maximum speed, acceleration, steering, etc., in order to maintain balance even with one wheel unit lifted from ground. The proposed solution also includes, in some examples, to also check whether lifting of the particular wheel unit, and in particular transitioning the vehicle to the new state, is motivated in terms of energy expense, as it may sometimes be more energy efficient to leave the vehicle as is and instead call for backup assistance from e.g. a tow truck or mobile service unit or similar.

[0099] The terminology used herein is for the purpose of describing particular aspects only and is not intended to be limiting of the disclosure. As used herein, the singular forms "a," "an," and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. As used herein, the term "and / or" includes any and all combinations of one or more of the associated listed items. It will be further understood that the terms "comprises," "comprising," "includes," and / or "including" when used herein specify the presence of stated features, integers, actions, steps, operations, elements, and / or components,but do not preclude the presence or addition of one or more other features, integers, actions, steps, operations, elements, components, and / or groups thereof.

[0100] It will be understood that, although the terms first, second, etc., may be used herein to describe various elements, these elements should not be limited by these terms. These terms are only used to distinguish one element from another. For example, a first element could be termed a second element, and, similarly, a second element could be termed a first element without departing from the scope of the present disclosure.

[0101] Relative terms such as "below" or "above" or "upper" or "lower" or "horizontal" or "vertical" may be used herein to describe a relationship of one element to another element as illustrated in the Figures. It will be understood that these terms and those discussed above are intended to encompass different orientations of the device in addition to the orientation depicted in the Figures. It will be understood that when an element is referred to as being "connected" or "coupled" to another element, it can be directly connected or coupled to the other element, or intervening elements may be present. In contrast, when an element is referred to as being "directly connected" or "directly coupled" to another element, there are no intervening elements present.

[0102] Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure belongs. It will be further understood that terms used herein should be interpreted as having a meaning consistent with their meaning in the context of this specification and the relevant art and will not be interpreted in an idealized or overly formal sense unless expressly so defined herein.

[0103] It is to be understood that the present disclosure is not limited to the aspects described above and illustrated in the drawings; rather, the skilled person will recognize that many changes and modifications may be made within the scope of the present disclosure and appended claims. In the drawings and specification, there have been disclosed aspects for purposes of illustration only and not for purposes of limitation, the scope of the disclosure being set forth in the following claims.

[0104] The following is an exemplifying list of examples envisaged herein:Example 1 : A computer system (150, 450, 500, 600) for a heavy vehicle or vehicle unit (100, 300, 400, 401, 402, A, B) equipped with a plurality of wheel units (112, 312) and an active suspension (630), wherein the computer system includes processing circuitry (610)configured to: - obtain an indication (620) about a desire to lift a particular one of the wheel units (112, 312) of the vehicle or vehicle unit from ground; - use a model (640) of the vehicle or vehicle unit to determine whether the particular wheel unit is individually liftable from ground using the active suspension without the vehicle or vehicle unit tipping over, and - in response to an affirmative outcome of said determining, control (650) the active suspension to individually lift the particular wheel unit from ground.Example 2: The computer system of example 1, wherein the particular wheel unit is arranged on an axle (110) of the vehicle or vehicle unit, and wherein to individually lift the particular wheel unit from ground includes to not lift another wheel unit (114) arranged on an opposite side of the same axle.Example 3: The computer system of example 1 or 2, wherein the processing circuitry is further configured to: - obtain suspension capability information (682) pertinent to a current capability of the active suspension, and - in response to a non-affirmative outcome of said determining, use the model of the vehicle or vehicle unit to further determine whether the vehicle or vehicle unit can, in accordance with the obtained suspension capability information and by using the active suspension, be transitioned to a new state in which the particular wheel unit is liftable from ground without the vehicle or vehicle unit tipping over and, - in response to an affirmative outcome of said further determining, control the active suspension to transition the vehicle or vehicle unit to the new state and lift the particular wheel unit from ground.Example 4: The computer system of example 3, wherein transitioning the vehicle or vehicle unit to the new state includes shifting a normal load (Fzi) on the particular wheel unit to one or more other of the wheel units.Example 5: The computer system of example 4, wherein shifting the normal load includes moving a center of gravity (COG) of the vehicle or vehicle unit (300) using the active suspension.Example 6: The computer system of example 3 or 4, wherein shifting the normal load includes using a stiffness of a chassis of the vehicle and a roll movement caused by the active suspension.Example 7: The computer system of any one of examples 3 to 6, wherein the processing circuitry is further configured to control the active suspension to lift the particular wheel from ground only after also confirming that an energy required to perform such a lifting of theparticular wheel unit and / or transitioning of the vehicle or vehicle unit to the new state is below an energy threshold.Example 8: The computer system of any one of examples 3 to 7, wherein the suspension capability information includes at least one of: i) current normal load forces (Fzi) on each of a plurality of wheel units of the vehicle or vehicle unit including the particular wheel unit; ii) limitations for possible normal load forces on each of the plurality of wheel units after adjusting the active suspension; and iii) limitations for possible distances (dzi) between each of the plurality of wheel units and a chassis of the vehicle or vehicle unit and / or for possible vertical displacements / heights of the wheel units.Example 9: The computer system of any one of the preceding examples, wherein the model of the vehicle or vehicle unit includes a mapped knowledge of a loaded vehicle or vehicle unit weight distribution and standard wheel height level positions.Example 10: The computer system of any one of the preceding examples, wherein the model of the vehicle or vehicle unit includes mapped knowledge about how normal loads on one or more wheel units of the vehicle depend on at least one of a roll, pitch, heave and individual wheel unit height positions of the vehicle or vehicle unit.Example 11 : The computer system of any one of the preceding examples, wherein using the model of the vehicle or vehicle unit to determine that the particular wheel unit is liftable includes to: - obtain a size of a normal load force (FZ1) applied on the particular wheel unit (312, w- as well as a total normal load force (Fztotai= FZ1+ FZ2+ FZ3+ FZ4) of the vehicle or vehicle unit (300), wherein the particular wheel unit and a first other wheel unit (314, w2) of the vehicle or vehicle unit are arranged on a first axle (310) of the vehicle or vehicle unit and second and third other wheel units (322, w3324, w4) of the vehicle or vehicle unit are arranged on opposite sides of another, second axle (320) of the vehicle or vehicle unit, wherein the particular wheel unit and the second other wheel unit are on a same side of the vehicle or vehicle unit, and - verify that i) the normal load force on the particular wheel unit times a distance (F- from the particular wheel unit to a first diagonal (d23) formed between the first and second other wheel units exceeds a sum of the total normal load force times a distance (q) from a center-of-gravity (COG) of the vehicle or vehicle unit to the first diagonal, and ii) the center-of-gravity of the vehicle or vehicle unit is on an opposite side of the first diagonal than the particular wheel unit.Example 12: The computer system of any one of the preceding examples, wherein the processing circuitry is further configured to: - determine whether a differential (170) of an axle (110) to which the particular wheel unit (112) belongs is an open differential, and - in response to an affirmative outcome of said determining, control a braking system (174) of the vehicle or vehicle unit to apply brake force on the particular wheel unit proportional to a brake force applied on another wheel (114) unit arranged on an opposite side of the same axle.Example 13: The computer system of any one of the preceding examples, wherein the processing circuitry is further configured to: - obtain an indication about a desire to loosen and / or tighten one or more wheel bolts or nuts of the particular wheel unit, and - control a motion support device, MSD, of the vehicle or vehicle unit to rotate the particular wheel unit once the particular wheel unit is lifted from ground.Example 14: The computer system of any one of the preceding examples, wherein the processing circuitry is further configured to: - transition the vehicle or vehicle unit to a limphome mode, in which the vehicle or vehicle unit is allowed to be driven at a limited speed and / or with a limited steering with the particular wheel unit lifted from ground.Example 15: The computer system of any one of the preceding examples, wherein to control the active suspension to lift the particular wheel from ground includes to compensate wheel height levels of one or more other wheels of the vehicle or vehicle unit such that a normal load on the particular wheel unit is zero.Example 16: A vehicle or vehicle unit (100, 300, 400, 401, 402, A, B), including: - a plurality of wheel units (112, 114, 122, 124) arranged on multiple axles (110, 120) of the vehicle or vehicle unit; - an active suspension (630) for controlling a distance (dzij between each wheel unit and a chassis of the vehicle or vehicle unit, and - the computer system (150, 450, 500, 600) of any one of examples 1 to 15.Example 17: The vehicle or vehicle unit of example 16, wherein the vehicle or vehicle unit has a total of two axles each having a transverse pair of wheel units.Example 18: The vehicle or vehicle unit of example 16, wherein the vehicle or vehicle unit is an articulated bus (401) formed by at least two vehicle units (A, B), and wherein at least one of said two vehicle units (A) has a total of two axles (410a, 420a) each having a transverse pair of wheel units (412a; 422a).Example 19:A computer-implemented method (200) for lifting a particular wheel unit of a heavy vehicle or vehicle unit equipped with a plurality of wheel units and an active suspension, wherein the method includes: - obtaining (S210), by processing circuitry of a computer system, an indication about a desire to lift a particular wheel unit of the vehicle or vehicle unit from ground; - using, by the processing circuitry, a model of the vehicle or vehicle unit to verify (S220) that the particular unit is individually liftable from ground using the active suspension without the vehicle or vehicle unit tipping over, and - in response to said determining, controlling (S230), by the processing circuitry, the active suspension to individually lift the particular wheel unit from ground. Example 20: A computer program product (514) including program code (520) for performing, when executed by a processing circuitry (502) of a computer system (500), the method of example 19.Example 21 : A non-transitory computer-readable storage medium (514) including instructions (520), which when executed by a processing circuitry (502) of a computer system (500), cause the processing circuitry to perform the method of example 19.

Claims

ClaimsWhat is claimed is:

1. A computer system (150, 450, 500, 600) for a heavy vehicle or vehicle unit (100, 300, 400, 401, 402, A, B) equipped with a plurality of wheel units (112, 312) and an active suspension (630), wherein the computer system comprises processing circuitry (610) configured to:- obtain an indication (620) about a desire to lift a particular one of the wheel units (112, 312) of the vehicle or vehicle unit from ground;- use a model (640) of the vehicle or vehicle unit to determine whether the particular wheel unit is individually liftable from ground using the active suspension without the vehicle or vehicle unit tipping over, and- in response to an affirmative outcome of said determining, control (650) the active suspension to individually lift the particular wheel unit from ground.

2. The computer system of claim 1, wherein the particular wheel unit is arranged on an axle (110) of the vehicle or vehicle unit, and wherein to individually lift the particular wheel unit from ground comprises to not lift another wheel unit (114) arranged on an opposite side of the same axle.

3. The computer system of claim 1 or 2, wherein the processing circuitry is further configured to:- obtain suspension capability information (682) pertinent to a current capability of the active suspension, and- in response to a non-affirmative outcome of said determining, use the model of the vehicle or vehicle unit to further determine whether the vehicle or vehicle unit can, in accordance with the obtained suspension capability information and by using the active suspension, be transitioned to a new state in which the particular wheel unit is liftable from ground without the vehicle or vehicle unit tipping over and,- in response to an affirmative outcome of said further determining, control the active suspension to transition the vehicle or vehicle unit to the new state and lift the particular wheel unit from ground.

4. The computer system of claim 3, wherein transitioning the vehicle or vehicle unit to the new state comprises shifting a normal load (Fzi) on the particular wheel unit to one or more other of the wheel units.

5. The computer system of claim 4, wherein shifting the normal load comprises moving a center of gravity (COG) of the vehicle or vehicle unit (300) using the active suspension.

6. The computer system of claim 3 or 4, wherein shifting the normal load comprises using a stiffness of a chassis of the vehicle and a roll movement caused by the active suspension.

7. The computer system of any one of claims 3 to 6, wherein the processing circuitry is further configured to control the active suspension to lift the particular wheel from ground only after also confirming that an energy required to perform such a lifting of the particular wheel unit and / or transitioning of the vehicle or vehicle unit to the new state is below an energy threshold.

8. The computer system of any one of claims 3 to 7, wherein the suspension capability information comprises at least one of: i) current normal load forces (Fzi) on each of a plurality of wheel units of the vehicle or vehicle unit including the particular wheel unit; ii) limitations for possible normal load forces on each of the plurality of wheel units after adjusting the active suspension; and iii) limitations for possible distances (dzi) between each of the plurality of wheel units and a chassis of the vehicle or vehicle unit and / or for possible vertical displacements / heights of the wheel units.

9. The computer system of any one of the preceding claims, wherein the model of the vehicle or vehicle unit comprises a mapped knowledge of a loaded vehicle or vehicle unit weight distribution and standard wheel height level positions.

10. The computer system of any one of the preceding claims, wherein the model of the vehicle or vehicle unit comprises mapped knowledge about how normal loads on one or morewheel units of the vehicle depend on at least one of a roll, pitch, heave and individual wheel unit height positions of the vehicle or vehicle unit.

11. The computer system of any one of the preceding claims, wherein using the model of the vehicle or vehicle unit to determine that the particular wheel unit is liftable comprises to:- obtain a size of a normal load force (FZ1) applied on the particular wheel unit (312, w- as well as a total normal load force (Fztotai = FZ1+ FZ2+ FZ3+ FZ4) of the vehicle or vehicle unit (300), wherein the particular wheel unit and a first other wheel unit (314, w2) of the vehicle or vehicle unit are arranged on a first axle (310) of the vehicle or vehicle unit and second and third other wheel units (322, w3; 324, w4) of the vehicle or vehicle unit are arranged on opposite sides of another, second axle (320) of the vehicle or vehicle unit, wherein the particular wheel unit and the second other wheel unit are on a same side of the vehicle or vehicle unit, and- verify that i) the normal load force on the particular wheel unit times a distance (Fx) from the particular wheel unit to a first diagonal (d23) formed between the first and second other wheel units exceeds a sum of the total normal load force times a distance (q) from a center-of-gravity (COG) of the vehicle or vehicle unit to the first diagonal, and ii) the center- of-gravity of the vehicle or vehicle unit is on an opposite side of the first diagonal than the particular wheel unit.

12. The computer system of any one of the preceding claims, wherein the processing circuitry is further configured to:- determine whether a differential (170) of an axle (110) to which the particular wheel unit (112) belongs is an open differential, and- in response to an affirmative outcome of said determining, control a braking system (174) of the vehicle or vehicle unit to apply brake force on the particular wheel unit proportional to a brake force applied on another wheel (114) unit arranged on an opposite side of the same axle.

13. The computer system of any one of the preceding claims, wherein the processing circuitry is further configured to:- obtain an indication about a desire to loosen and / or tighten one or more wheel bolts or nuts of the particular wheel unit, and- control a motion support device, MSD, of the vehicle or vehicle unit to rotate the particular wheel unit once the particular wheel unit is lifted from ground.

14. The computer system of any one of the preceding claims, wherein the processing circuitry is further configured to:- transition the vehicle or vehicle unit to a limp-home mode, in which the vehicle or vehicle unit is allowed to be driven at a limited speed and / or with a limited steering with the particular wheel unit lifted from ground.

15. The computer system of any one of the preceding claims, wherein to control the active suspension to lift the particular wheel from ground comprises to compensate wheel height levels of one or more other wheels of the vehicle or vehicle unit such that a normal load on the particular wheel unit is zero.

16. A vehicle or vehicle unit (100, 300, 400, 401, 402, A, B), comprising:- a plurality of wheel units (112, 114, 122, 124) arranged on multiple axles (110, 120) of the vehicle or vehicle unit;- an active suspension (630) for controlling a distance dzi) between each wheel unit and a chassis of the vehicle or vehicle unit, and- the computer system (150, 450, 500, 600) of any one of claims 1 to 15.

17. The vehicle or vehicle unit of claim 16, wherein the vehicle or vehicle unit has a total of two axles each having a transverse pair of wheel units.

18. The vehicle or vehicle unit of claim 16, wherein the vehicle or vehicle unit is an articulated bus (401) formed by at least two vehicle units (A, B), and wherein at least one of said two vehicle units (A) has a total of two axles (410a, 420a) each having a transverse pair of wheel units (412a; 422a).

19. A computer-implemented method (200) for lifting a particular wheel unit of a heavy vehicle or vehicle unit equipped with a plurality of wheel units and an active suspension, wherein the method comprises:- obtaining (S210), by processing circuitry of a computer system, an indication about a desire to lift a particular wheel unit of the vehicle or vehicle unit from ground;- using, by the processing circuitry, a model of the vehicle or vehicle unit to verify (S220) that the particular unit is individually liftable from ground using the active suspension without the vehicle or vehicle unit tipping over, and- in response to said determining, controlling (S230), by the processing circuitry, the active suspension to individually lift the particular wheel unit from ground.

20. A computer program product (514) comprising program code (520) for performing, when executed by a processing circuitry (502) of a computer system (500), the method of claim 19.

21. A non-transitory computer-readable storage medium (514) comprising instructions (520), which when executed by a processing circuitry (502) of a computer system (500), cause the processing circuitry to perform the method of claim 19.

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