Handling of vehicle in case of steering system failure

Abstract

A computer system (200) for a (heavy) vehicle equipped with an active wheel suspension (230) is provided. Processing circuitry (210) is configured to obtain an indication (220) of an occurring or imminent failure of an ordinary steering system (222), and in response to obtaining such an indication control (250) the active suspension in accordance with a particular sequence of vehicle roll angles, as part of generating vehicle yaw moment to steer the vehicle using the active suspension instead of the ordinary steering system. A corresponding (heavy) vehicle, method, computer program product and storage medium are also provided.

Description

HANDLING OF VEHICLE IN CASE OF STEERING SYSTEM FAILURETECHNICAL FIELD

[0001] The disclosure relates generally to the field of heavy vehicles having height adjustable suspension, such as an active suspension. In particular aspects, the disclosure relates to handling (such as steering) of such vehicles in case of failure of a steering system of the vehicle. 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] A steering system of a vehicle is responsible for controlling the vehicle in a desired direction, and thereby forms a vital part of the overall vehicle configuration. The steering system may e.g. include a steering wheel, mechanical linkage, electronics, steering assist servos, or even fully steer-by-wire systems. Although vital to the performance and / or functioning of the vehicle, steering systems are not immune to failure. For this reason there are various solutions available which, in case the steering system where to fail, relies on using the brakes and / or propulsion of the vehicle to carry out a so-called safe stop in which the vehicle is directed to a side of the road and brought to a halt. For example, by applying different brake forces to different wheels, e.g. by braking one side of the vehicle differently from the other side, the direction of the vehicle may at least partially be controlled by generating suitable yaw moment. The same principle applies also in case it may be controlled how much propulsion torque that is provided to each side of the vehicle, such that the vehicle’s direction of movement may be affected by adjusting the applied propulsion torques accordingly.

[0003] The present disclosure aims at facilitating the handling of a vehicle in case of steering system failure, to reduce the risk of accidents and to improve upon contemporary solutions for such situations.SUMMARY

[0004] According to a first aspect of the present disclosure, there is provided a computer system for a (heavy) vehicle equipped with an active suspension (system), such as an active wheel or wheel unit suspension (system). The computer system includes processing circuitry configured to: obtain an indication of an occurring or imminent failure of an ordinary steering system of the vehicle; in response to obtaining the indication, control the active suspension of the vehicle in accordance with at least one particular sequence of vehicle roll angles, as part of generating (or creating) vehicle yaw moment to steer the vehicle using height-adjustable suspension instead of the ordinary steering system. The first aspect of the present disclosure may seek to improve the handling of the vehicle during failure of the ordinary steering system, such that the suspension of the vehicle takes over all or part of the responsibility of the ordinary steering system during failure of the latter. A technical benefit may include that using the active suspension to generate vehicle body roll may provide a more efficient way of generating the yaw moment required to steer the vehicle, instead of or in addition to e.g. steering-by-braking and / or steering-by-propulsion.

[0005] Optionally in some examples, including in at least one preferred example, the processing circuitry may be further configured to, as part of generating vehicle yaw moment, also control a propulsion (system) of the vehicle. A technical benefit may include that combining the use of the active suspension also with the propulsion may provide a more efficient (emergency) steering of the vehicle.

[0006] Optionally in some examples, including in at least one preferred example, the processing circuitry may be further configured to, as part of generating vehicle yaw moment, use a map or model-based algorithm indicating one or more yaw moments resulting from given vehicle roll angles. A technical benefit may include that the control of the active suspension can be made more efficient, without having to rely on trial-and-error procedures and similar.

[0007] Optionally, in some examples, including in at least one preferred example, the processing circuitry may be further configured to determine the at least one particular sequence of vehicle roll angles from a set of one or more predetermined sequences of vehicle roll angles. A technical benefit may include that the computer system does not need to spend critical time on recalculating such sequences for each new emergency situation, but may relyon precalculated sequences corresponding to e.g. one or more maneuvers of the vehicle that has been proven (statistically) useful in the past.

[0008] Optionally, in some examples, including in at least one preferred example, the processing circuitry may be further configured to: obtain a warning about an imminent risk of colliding with an object ahead of the vehicle, and, determine the at least one particular sequence of vehicle roll angles as at least one sequence of vehicle roll angles suitable to avoid collusion with the object ahead. As mentioned above, a technical benefit may include that a suitable sequence of vehicle roll angles may be found more quickly than if attempting to recalculate such a sequence from scratch.

[0009] Optionally, in some examples, including in at least one preferred example, the at least one particular sequence of vehicle roll angles may be pertinent to (i.e. result in / correspond to) a lane-changing maneuver for the vehicle.

[0010] Optionally, in some examples, including in at least one preferred example, the at least one particular sequence of vehicle roll angles may be pertinent to a pull-to-curb or pull- to-side maneuver for the vehicle.

[0011] Optionally, in some examples, including in at least one preferred example, the processing circuitry may be further configured to, as part of generating the vehicle yaw moment, control also a braking (system) of the vehicle. A technical benefit may include that the steering may thus be made more efficient in emergency situations, by complementing the use of the active suspension to steer the vehicle with one or both of the propulsion and braking (systems) of the vehicle.

[0012] Optionally, in some examples, including in at least one preferred example, the processing circuitry may be further configured to obtain an indication that an emergency or escape lane (such as a brake-down lane) is available ahead of the vehicle, and to determine the at least one particular sequence of vehicle roll angles as at least one sequence of vehicle roll angles suitable to steer the vehicle into the emergency or escape lane. A technical benefit may include that such lanes may provide for a safer stop of the vehicle, especially if a speed of the vehicle is high when the ordinary steering brakes down.

[0013] Optionally, in some examples, including in at least one preferred example, the processing circuitry may be further configured to obtain suspension capability information pertaining to a current capability of the active suspension of the vehicle, and to control the active suspension also based on the suspension capability information. A technical benefit oftaking the capabilities of the suspension into account may include that more energy efficient solutions are obtained, more accurate and quicker ways of steering the vehicle to a desired location after the ordinary steering system failure, and / or that solutions that are theoretically but not practically possible are avoided completely or at least more often. The suspension capability information may e.g. include information about possible load transfers that may be achieved by the active suspension as currently configured, what actual vehicle roll angles that are physical possible given the current state of the vehicle’s active suspension, and similar. The suspension capability information may e.g. indicate that one or more actuators of the active suspension is currently not offering their full potential (due to e.g. being fully or partially damaged), and the computer system may take this into account when deciding how to operate the height-adjustable suspension to steer the vehicle by generating the sequence of vehicle roll angles for steering.

[0014] Optionally, in some examples, including in at least one preferred example, the processing circuitry may be further configured to obtain the suspension capability information and control the active suspension of the vehicle via a same suspension control / capability interface. A technical benefit may include that the computer system can be made agnostic to the exact configuration of the active suspension, and include all information required via the interface only. For example, the computer system may thus not be required to have any hardcoded data about e.g. various types of suspension actuators, their capabilities, etc. programmed into its memory, but may receive any such information (as needed) from the interface. Likewise, the computer system may not need to be explicitly configured to communicate with a particular actuator or control system of the active suspension, but both the control and readout of capabilities may instead be performed via the interface which may be standardized such that how to communicate with the interface does not depend on the exact configuration of the active suspension.

[0015] According to a second aspect of the present disclosure, there is provided a heavy vehicle. The vehicle includes an active suspension (such as an active wheel or wheel unit suspension), a steering system for ordinary steering of the vehicle, and the computer system of the first aspect (or any embodiment thereof disclosed herein).

[0016] Optionally, in some examples, including in at least one preferred example, of the vehicle, the active wheel suspension may be a gas-hydraulic wheel suspension and / or pneumatic wheel suspension.

[0017] According to a third aspect of the present disclosure, there is provided a computer- implemented method for steering of a (heavy) vehicle having an active (wheel / wheel unit) suspension during steering system failure. The method includes obtaining, by processing circuitry of a computer system (such as the computer system of the first aspect or embodiments thereof described herein), an indication about an occurring or imminent failure of an ordinary steering system of the vehicle, and, in response to obtaining the indication, controlling the active suspension of the vehicle in accordance with at least one particular sequence of vehicle roll angles, as part of generating vehicle yaw moment to steer the vehicle using the active suspension instead of the ordinary steering system.

[0018] According to a fourth aspect of the present disclosure, there is provided a computer program product including program code (e.g. instructions) for performing, when executed by a processing circuitry of a computer system (such as the computer system of the first aspect or embodiments thereof described herein), the method of the third aspect (or any embodiments thereof disclosed herein).

[0019] According to a fifth aspect of the present disclosure, there is provided a computer- readable storage medium comprising instructions, which when executed by a processing circuitry of a computer system (such as the computer system of the first aspect or embodiments thereof described herein), cause the processing circuitry to perform the method of the third aspect (or any embodiments thereof described herein). The storage medium may be non-transitory.

[0020] 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.

[0021] 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 benefitsBRIEF DESCRIPTION OF THE DRAWINGS

[0022] Examples are described in more detail below with reference to the appended drawings.

[0023] FIGS. 1A and IB schematically illustrate an exemplary vehicle, in form of a bus, equipped with an active suspension, according to examples of the present disclosure.

[0024] FIG. 2 schematically illustrates an exemplary computer system according to examples of the present disclosure.

[0025] FIGS. 3A and 3B schematically illustrate exemplary use-cases according to examples of the present disclosure.

[0026] FIG. 4 schematically illustrates a flowchart of an exemplary method according to an example of the present disclosure.

[0027] FIG. 5 schematically illustrates a diagram of an exemplary computer system for implementing examples disclosed herein, according to an example.DETAILED DESCRIPTION

[0028] 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.

[0029] Figs. 1A and IB schematically illustrates an exemplary heavy vehicle 100 according to an example, in form of a bus. This particular vehicle 100 has a front and rear (wheel) axles 110 and 120, respectively. The front axle 110 includes left and rear wheel units 112 and 114, respectively, and the rear axle 120 includes left and right wheel units 122 and 124, respectively. Herein, a “wheel unit” may be a single wheel, a set of dual wheels, a set of triple wheels, or similar. In the particular example illustrated in FIGS. 1 A and IB, the wheel units 112 and 114 are each single wheels, while the wheel units 122 and 124 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 100, and the second axel 120 is a driven rear axle of the vehicle 100.

[0030] A vehicle as envisaged herein may be at least partially or fully electric, wherein one or more electrical machines are used to propel the vehicle. In other examples as envisaged herein, propulsion may instead be provided by one or more internal combustion engines (ICEs). In any case, it is envisaged that the vehicle has at least one driven axle.

[0031] The vehicle 100 is further equipped with an active suspension, that allows to individually control a distance between each wheel unit 112, 114, 122 and 124 and a chassis of the vehicle 100 in a vertical direction. In this particular example, the active suspensionincludes 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. Other examples of how to implement a gas-hydraulic suspension is of course also envisaged and suitable for use within the realm of the present disclosure. In other examples, if the cylinders 130a-d are instead airsprings, 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. Spring action can be provided by compression of the air, and the amount of sprint action can be adjusted by changing the air volume within each cylinder. Likewise, damping action may be provided by e.g. controlled throttling of a flow of air to / from each cylinder, and similar. Other examples are also envisaged, as long as these alternatives allow to adjust the distances as described above.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 further spring action is required. Independently of 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 dynamically, i.e. based on a control signal and via use of one or more actuators, instead of by mechanical adjustment performed by hand. Such active suspensions are commonly known and available to the skilled person.

[0032] 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 anyof 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 on or more pressure providing elements, such as a compressor, to provide sufficient fluid pressure in the active suspension system.

[0033] 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 or be included as part of, a computer system 150, and is configured to e.g. control the active suspension to individually adjust the distance between each wheel unit 112, 114, 122, 124 and the chassis of the vehicle 100.

[0034] 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 vehicle 100, 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 and / or a current operational state 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. Herein, it is assumed that the computer system 150 is capable of receiving at least an indication of a working condition for a steering system of the vehicle 100, such as including the steering wheel 162 and / or a steering servo 172 used to provide assisted (servo) steering of the vehicle 100, or similar.

[0035] The computer system 150 may also be communicatively coupled to, and e.g. capable of controlling, a transmission / propulsion system 174 of the vehicle 100 responsible for e.g. propelling and / or braking the vehicle 100 (in FIGS. 1 A and IB), the braking systemof the vehicle is not explicitly shown. 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 communicate with / control one or more other parts of the vehicle 100. In some examples, one, more or all such units required to perform a certain functionality being recited herein as “performed by the computer system” are assumed to be included as part of the computer system 150.

[0036] 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. a map or model -based algorithm that may be used to indicate e.g. one or more yaw moments resulting from given vehicle roll angles, and similar, as will be described in more detail later herein, and optionally one or more other models and / or algorithms descriptive of vehicle behavior. As used herein, a model descriptive of a vehicle behavior may include a static, dynamic and / or kinematic mode of the vehicle.

[0037] 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 (and / or changing rates) on each of the wheel units 112, 114, 122 and 124 after adjusting the active suspension, and / or limitations for possible distances (and / or changing rates) 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 othersensors (not shown) capable of providing such information about the active suspension capabilities.

[0038] The control unit 150 may further be configured to communicate with (i.e. at least receive data from) one or more sensors 190 of the vehicle 190, such as e.g. one or more cameras, radars, LIDARs, ultra-sonic sensors, and similar, that may be used to e.g. detect whether there is an imminent risk of colliding with an object ahead of the vehicle 100. For example, sensors 190 (such as e.g. cameras, radars, LIDARs, etc.) may scan the section of road ahead of the vehicle 100, and use e.g. image processing, sensor fusion, occupancy grid methods, and similar, to detect objects or abnormalities ahead of the vehicle, and the control unit 150 may process such data in order to e.g. estimate a risk of colliding with such an object, taking into account e.g., if necessary, other factors such as a speed and direction of the own vehicle 100, road surface conditions, speed and direction of the object, and similar. If the risk is deemed as exceeding e.g. a threshold, a warning about the imminent risk of collision may be issued and acted upon by the control unit 150 as will be described in more detail later herein.

[0039] The present disclosure aims at solving, or at least alleviating, the problem of what to do in case of a breakdown / failure of the ordinary steering system, such as e.g. one or more problems / failures of the steering wheel 162, the steering servo(s) 172 or any other failure (such as mechanical failure) of one or more components necessary for the ordinary steering system to operate as desirable. In particular, the present disclosure proposes to solve this problem or problems by using the active suspension of the vehicle 100 to steer the vehicle 100 in case the ordinary steering system fails.

[0040] How the computer system 150 is envisaged to operate to solve this task using the active suspension will now be described in more detail with reference also to FIG. 2.

[0041] FIG. 2 schematically illustrates an exemplary computer system 200 according to one or more examples of the present disclosure. The computer system 200 may be the control unit 150 or at least be used to implement the functionality of the control unit 150 as described herein. The computer system 200 includes processing circuitry 210 that is configured to obtain an indication (via e.g. a message 220) of an occurring or imminent failure of an ordinary steering system 222 of the vehicle. In response to obtaining such an indication, the processing circuitry 210 is further configured to control (by issuing one or more control messages 250 thereto) an active suspension 230 of the vehicle. As used herein, a “message”may be a signal on any form suitable for conveying a message between two entities or functional modules / unit, such as e.g. an electric signal, an optical signal, an electromagnetic signal, a mechanical signal, and similar. The processing circuitry 210 is configured to control the active suspension 230 in accordance with at least one particular sequence of vehicle roll angles, as part of (e.g. in order to create / generate) vehicle yaw moment Mz(such as e.g. shown in FIG. 1 A). This in order to steer the vehicle using the active suspension 230 instead of the ordinary steering system 222. The indication 220 may for example be received from one or more sensors of the vehicle responsible for detecting a breakdown of the ordinary steering system 222. As used herein, vehicle roll angles may include e.g. separate roll angles for different wheel axles (such as e.g. the front and rear wheel axles 110 and 120 of the vehicle 100 illustrated in FIG. 1A).

[0042] In some examples, it is envisaged that the control unit 150 may determine one or more such sequences of vehicle roll angles on-the-fly, e.g. in response to the steering system failure and based on e.g. a current situation around the vehicle, such as identified objects ahead of the vehicle, a configuration of the road ahead, prevailing road conditions (such as friction coefficient estimates), a currently loading / weight distribution of the vehicle, and similar.

[0043] In some examples, the processing circuitry 210 may be configured to also control a propulsion 262 of the vehicle, e.g. by issuing a control message 260, as part of generating the vehicle yaw moment Mz. In yet other examples, the processing circuitry 210 may be configured to also (in addition to, or instead of controlling the propulsion 262) control a braking of the vehicle, e.g. by issuing a control message 290 to a braking system 292 of the vehicle.

[0044] In general, a desirable yaw moment Mzmay be generated by requesting particular roll angles for the vehicle, e.g. for the front and rear axles 110 and 120. For example, a relationship between radius of path ( / ?p), vehicle roll angle(s) (0ron(,i), where i indicates a particular axle), and vehicle velocity / speed may be established and used to determine what roll angles to request in order to steer according to Rpat a particular velocity / speed. If assuming that e.g. Rpis constant for a given vehicle roll angle 6 regardless of vehicle speed v, it may be assumed that yaw moment Mzwill increase with increased velocity v. A relationship between e.g. yaw rate (or yaw velocity), e.g. 0yawwhere 0yawis a yaw angle ofthe vehicle, and yaw moment Mzmay also be established and used as part of steering the vehicle using the active suspension 230. For example, if assuming that Rpis constant regardless of vehicle speed v, a simple relation may be established as 0yaw= v / Rp. If experiments for a particular vehicle show that Rpis not independent of vehicle speed v, a more complex relationship may be established e.g. based on experimental and / or modelbased data for the vehicle., e.g. such that 0yawwhere f is some function relating yaw rate and yaw moment.

[0045] The yaw moment Mzmay also be influenced using the propulsion 262 and / or braking 290 of the vehicle, such as when performing torque vectoring. For example, by applying negative torques (i.e. braking) on one side of the vehicle, and by applying positive torques (i.e. propulsion) on the other side of the vehicle, a contribution to the yaw moment Mzwanting to turn the vehicle to the side on which negative torques are applied can be generated, and vice versa. For example, it may be established how Mzdepends on e.g. torque vectoring and steering angle, which may be affected by the active suspension system. The function f relating yaw rate and yaw moment may e.g. depend on various parameters such as wheel axles cornering stiffness, effective rolling radius of wheel units, axle track width, distance from vehicle center of gravity (COG) to the wheel axle, and similar. Using e.g. a single-track model of the vehicle, one may for example notice that yaw rate depend not only on the yaw moment but also on e.g. vehicle states such as longitudinal and lateral velocities of the vehicle. Herein, it is thus envisaged that in some examples, the computer system 200 and processing circuitry 210 are configured to control the propulsion 262 and / or braking system 292 of the vehicle, e.g. by sending suitable control messages 260 and 290, respectively, to these entities.

[0046] As used herein, “to steer the vehicle” may also be referred to as to “perform a steering maneuver”, “perform a yaw maneuver”, or similar. Of course, part of an overall steering sequence may also include e.g. keeping the vehicle at a straight course (i.e. with no turning of the vehicle) between two or more other parts of the sequence (where turning is desirable).

[0047] In some examples, the sequence of vehicle roll angles may be selected from a plurality of predetermined sequences of vehicle roll angles. For example, it is envisaged to pre-calculate sequences of vehicle roll angles corresponding to different “standard”maneuvers of the vehicle. For example, one such maneuver may be a “turn right and then (immediately) turn left” maneuver, while another such maneuver may be a “turn left and then (immediately) turn right” maneuver, etc. In other examples, more simple maneuvers such as “turn left”, “turn right”, “turn straight after having turned left”, “turn straight after having turned right”, etc., may also be stored, and combined in order to generate more complex maneuvers. The computer system 200 and processing circuitry 210 may then be configured to e.g. estimate what it would desire the vehicle to do in order to safely resolve the situation of a failed ordinary steering system 222, and then select one or more predetermined maneuvers (e.g. one or more predetermined sequences of vehicle roll angles) that would provide such a behavior of the vehicle. A sequence of vehicle roll angles may include a plurality of roll angles that are to be commanded in a particular order in order to cause a particular steering maneuver, such as a lane-changing maneuver, steer-to-curb / -side maneuver, or similar. As used herein, it is envisaged that the computer system is configured to determine when exactly to request / command each roll angle based on e.g. a current speed of the vehicle. For example, a sequence of vehicle roll angles may include timings of the roll angles for a baseline speed of the vehicle, and the computer may then adjust these timings of the roll angles based on a deviation of the current speed of the vehicle from the baseline speed, or similar. The computer system may also be further configured to take into account e.g. a current loading of the vehicle, road surface conditions, tire conditions, vehicle inertial moment and similar as part of deciding whether (and how) to modify the predetermined sequence of vehicle roll angles in accordance with a current state of the vehicle. As a trivial example, a sequence of vehicle roll angles may e.g. include instructions that for a vehicle driving at a baseline speed vbi, a lane-changing maneuver is caused by requesting e.g. one particular vehicle roll angle (or set of roll angles) at a first time instance t15and by requesting e.g. another particular vehicle roll angle (or set of roll angles) at a later, second time instance t2. For example, the sequence may include instructions to roll the vehicle with +X degrees at time t15and to then roll the vehicle with —X degrees at time t2, and similar. This is only one of many possible alternatives, and other sequences corresponding to other more or less complex maneuvers are of course also possible.

[0048] In some examples, the predetermined sequences of vehicle roll angles may also include corresponding target values for the braking and / or propulsion of the vehicle. For example, a particular maneuver may be defined as a sequence of vehicle roll angles, torquerequests, and similar, that in combination is assumed to generate the particular maneuver. If how to control e.g. the active suspension, braking and / or propulsion of the vehicle is not just linearly depending on e.g. vehicle velocity, there may e.g. be multiple sequences for a same type of maneuver, each corresponding to a different vehicle speed. If the exact speed of the vehicle does not correspond exactly to one such predetermined sequence, extrapolation and / or interpolation between e.g. two sequences for neighboring speeds may be used as an example of how to resolve such a situation, and similar. In particular, as envisaged herein, the used of a plurality of predetermined sequences (of at least vehicle roll angles) may help to avoid the computer system 200 having to calculate such sequences in real-time, especially when such real-time calculations are not possible or deemed undesirable for other reasons.

[0049] Such dependencies of yaw moment on e.g. vehicle roll angles (which are in turn affected by the active suspension 230) may for example be compiled into a map or modelbased algorithm indicative of one or more yaw moments resulting from given vehicle roll angles (and / or e.g. from given torque requests, vehicle speeds, etc.), and such a map or model-based algorithm may be used by the computer system 200 as part of deciding how to control the active suspension 230 in order to steer the vehicle. For example, such a map or model-based algorithm may be provided from a storage 242, e.g. as data 240, accessible from the computer system 200. For example, the map or model-based algorithm may e.g. take a particular desired yaw moment as input, and output one or more vehicle roll angles that it believes will result in the requested desired yaw moment. The computer system 200 may the control the active suspension 230 to generate such one or more vehicle roll angles (including e.g., in some examples, different roll angles for different wheel axles). The storage may also be used to store e.g. the predefined sequences of vehicle roll angles that correspond to different “standard” maneuvers of the vehicle.

[0050] In some examples, the computer system 200 and processing circuitry 210 may be further configured to receive a warning (e.g. message) 270 about an imminent risk of colliding with an object ahead of the vehicle and, in response thereto, determine which of the (e.g. predetermined) sequences of vehicle roll angles to use in order to generate a maneuver that avoids such a collision. As mentioned earlier herein, this may include combining two or more of the predetermined sequences, e.g. as part of extrapolation / interpolation and / or in order to generate more complex maneuvers than those of the corresponding predetermined sequences.

[0051] As mentioned earlier herein, the imminent collision warning 270 may e.g. be obtained from one or more sensors of the vehicle, such as one or more cameras 272, radars, LIDARs, and similar, or from some other unit in communication with such sensors, capable of detecting objects or other abnormalities ahead of the vehicle. In some examples, the computer system 200 and processing circuitry 210 may instead be configured to only receive raw data from the sensors (such as 272), and perform the required image processing, data fusion, occupancy grid detection methods, etc., necessary to detect and assess the risk of colliding with objects on its own, or at least perform one or more calculations complementary to those performed e.g. in the sensors 272.

[0052] The control system 200 and processing circuitry 210 may also be configured to communicate with an interface 280 (such as interface 180) from which suspension capability information (as described earlier herein, as part of e.g. a signal / message / indication 282) can be provided to the control system 200 and processing circuitry 210, such that the processing circuitry 510 may take the current capabilities of the active suspension 230 into account when e.g. determining how to control the active suspension 230 in order to steer the vehicle in case of steering system failure. In some examples, it is envisaged that the interface 280 may, in addition to providing suspension capabilities, also receive control commands for the active suspension 230, in which case the computer system 200 and processing circuitry 210 may instead (or in addition) control the active suspension 230 via the interface 280 (in which case the messaging / signaling / indicating 282 is two-way and the control message(s) 250 may not be needed). For example, the interface 280 may provide a standardized interface with a standardized set of possible control commands as well as e.g. a standardized set of suspension capabilities that are reported from the interface 280 to the computer system 200 and processing circuitry 210. As described earlier herein, this may be advantageous in that the computer system 200 may not need to know the exact configuration of the active suspension 230, as the interface 280 will serve as a translator between active suspension 230 specificdetails to a standardized language that the computer system 200 may understand.

[0053] The interface 280 may provide information such as current normal loads Fzion each i :th wheel unit, current distances / displacements dzi, current limits for Fziand / or dzi(i.e. F^F1and / or d^1), current limits for changes of Fziand / or dzi(i.e. AFz'mand / or Ad^1), and / or current rate of change limits dFzi / dt and / or d(dzi) / dt (e.g. “normal load changing rate limitations” and / or “level changing rate limitations”, e.g., andsimilar. Force limitations may in some examples include separate limits for e.g. raising and lowering of a wheel unit, etc.

[0054] If used to also control the active suspension, the interface 280 may for example receive commands such as requests for a particular normal load force Fzqto be exerted on the i :th wheel unit, a particular distanceto be configured for the i :th wheel unit, a particular change in normal load force ^Fzfq, a particular change in distance Adzi, a request to achieve a certain normal load force Fzqor change in normal load force ^F^qwhile remaining within a limitation in distancea request to achieve a certain distance dzriqor change in distance dzreqwhile remaining within a limitation in normal load forceand similar. In other example, the interface 280 may also, or instead, receive commands indicated requested wheel roll angles, such as 6, and may translate such commands into suitable commands for controlling the active suspension 230 in order to provide such vehicle roll angles.

[0055] Using the suspension capability information obtained from the interface 280 may provide a more efficient usage of the active suspension, e.g. by avoiding requesting normal load changes and / or wheel roll angles, that are not currently obtainable, and / or by e.g. taking into account whether all suspension actuators (such as cylinders) for the wheel units are working properly (as a failure or reduced capacity of a particular such actuator may be signaled by the interface 280 by e.g. reducing the reported rate of change limitations, or similar). If such failures or reduced capacities are reported, the computer system 200 and processing circuitry 210 may take that into account when deciding how to control the active suspension 230 to achieve particular maneuvers of the vehicle. Other advantageous uses of the reported suspension capability information in order to control the active suspension 230 to steer the vehicle are of course also possible. Although not shown in FIG. 2, there may of course be other such interfaces also for the braking system 292 and / or propulsion system 262, such that the computer system 200 can be made aware of the capabilities of also these entities and use such knowledge when deciding how to also control these entities to cause the desired maneuvers of the vehicle. Such interfaces may of course also be used to provide control commands, such that e.g. the messages 260 and / or 290 can be dropped and all communication with the propulsion system 262 and / or braking system 292 instead be handledvia such interfaces, making the computer system 200 agnostic also about the exact configurations of the propulsion system 262 and / or braking system 292.

[0056] As also envisaged herein, a decision to use either the active suspension, braking or propulsion system (or to what extend each of these systems is to be used) to achieve the final goal of steering the vehicle by generating vehicle yaw moment may also be taken by the computer system as described herein, based on information about e.g. how much energy each system will consume and / or how quickly the desired yaw moment can be generated by each system (or by combination of two or more systems). For example, a cost function may be provided for each system (e.g. for the active suspension, propulsion and braking system), and the controller may request the desired action based on the current situation. Such costs functions can be hardcoded into e.g. the computer system and / or obtained from the suspension capability interface and / or from such interfaces for the braking and propulsion systems. For example, if the desired maneuver is to pull the vehicle to a curb / side of the road under non-(time-)critical conditions, the control action may be something that uses the least amount of energy but takes a longer time. Likewise, if the desired maneuver is e.g. to avoid collision and thereby more (time-)critical, the control action may instead be something that is more quicker but also more energy consuming. As used herein, to “avoid a collision with an object” may also be referred to as e.g. “performing a (lateral) avoidance maneuver in respect of the object”, and similar.

[0057] Various example scenarios / situations (i.e. use-cases), and how the proposed solution may resolve a situation arising due to a failure of the ordinary steering system in such scenarios, will now be described in more detail with reference also to FIGS. 3A and 3B.

[0058] FIG. 3A schematically illustrates an exemplary set of scenarios 300. As a first such example, it is detected that a vehicle 100 as envisaged herein has a steering failure 310. In response thereto, it is determined that a particular sequence of vehicle roll angles (and optionally also corresponding control of the propulsion and / or braking system of the vehicle 100) will result in a pull-to-curb / -side maneuver 320 that is deemed suitable to resolve the negative situation as soon as possible. This may include identifying that there is a curb (or verge, or other suitable part on the side of the road) 330 where the vehicle 100 may safely stop, and that the maneuver 320 will result in a safe transitioning of the vehicle 100 to a stop at the curb 330. As another example, it may instead be determined that there is roadside parking area 340 or similar further up ahead, and a sequence of other vehicle roll angles mayinstead be selected which causes a maneuver 321 resulting in the vehicle being safely steered and stopped in the area 340. As yet another example, it is detected that there is a steering failure 311 for a vehicle 101, and an indication is received by the processing circuitry that that there is an emergency lane / escape lane 350 ahead of the vehicle 101. A particular sequence of vehicle roll angles (and optionally corresponding braking and / or propulsions requests) is determined as being able to cause a maneuver 322 that safely brings the vehicle101 into the lane 350, and the active suspension (and possibly also the braking and / or propulsion system) of the vehicle 101 is controlled accordingly to perform such a maneuver 322.

[0059] FIG. 3B schematically illustrates another exemplary set of scenarios 301. In one example, it is detected that there is a failure 312 of the ordinary steering system of a vehicle102 currently driving in a left L lane of a road. It is also issued / obtained a warning 313 about an imminent risk of the vehicle 102 colliding with an object 360 ahead of the vehicle 102 if no further action is taken. It can e.g. be assumed that braking of the vehicle 102 not sufficient to avoid colliding with the object 360 (in this case a damaged vehicle which is standing still on the road). It is determined that a particular sequence of vehicle roll angles will cause a (lane-changing) maneuver 323 that avoids the colliding with the object 360, and the active suspension (and optionally the braking and / or propulsion system) of the vehicle 102 is controlled accordingly to cause the maneuver 323 such that the vehicle 102 changes to the other, right R lane before / instead of colliding with the object 360. As it was detected that the steering system of the vehicle 102 is no longer operable, after having avoided the collision via the maneuver 323, a further sequence of vehicle roll angles may also be determined, causing a pull-to-curb / -side maneuver 324 such that the vehicle 102 is safely brought to a stop at the side 330 of the road. In another example, it is detected that there is a steering failure 314 of a vehicle 103, and that there is also an imminent risk 315 of the vehicle 103 colliding with an object 362 ahead of the vehicle 103 (such as a car standing still in the same, right R, lane as that currently driving in by the vehicle 103). A particular sequence of vehicle roll angles may be selected that results in a (lane-changing) maneuver 325 in which the vehicle 103 changes to the other, left L, lane of the road, such that the collision is avoided. It may then, due to the steering system of the vehicle 103 still being inoperable, be decided to select an additional sequence of vehicle roll angles that causes a maneuver 327 that brings the vehicle 103 to a safe stop along the side 330 of the road. Alternatively, it may be determinedthat it is safer to directly bring the vehicle 103 to a stop at the side 300 of the road and still avoid the collision with the object 362, by performing a maneuver 326 (i.e. a particular sequence of vehicle roll angles). In any case, control of the active suspension (and optionally also the braking and / or propulsion system) of the vehicle 103 avoids the collision with the object 362 and brings the vehicle 103 to a safe stop.

[0060] Numerous alternative scenarios are of course also possible, all including the same principle of i) detecting that there is a steering system failure of a vehicle, ii) selecting a sequence of vehicle roll angles (in accordance with a particular maneuver suitable for bringing the vehicle to a safe stop, potentially after also avoiding a collision), and iii) controlling the active suspension (and optionally also the braking and / or propulsion system of the vehicle) to perform such a maneuver. It is also envisaged that the active suspension may also be used to complement the ordinary steering system in case of partial breakdown of the latter. For example, if detecting that e.g. the steering servo is damaged such that the steering wheel is hard to turn for the driver, the active suspension (and possibly the braking and / or propulsion system) of the vehicle may be used to provide the requested vehicle yaw indicated by the position of the steering wheel. For example, if the steering wheel is heavy to turn for the driver and the driver attempts to turn the steering wheel clockwise in order to turn the vehicle to the right, the active suspension may be used to roll the vehicle such that such a steering request is obtained in the best way possible. How much to roll the vehicle may be determined as a function of steering wheel input, and possibly also based on e.g. a longitudinal speed of the vehicle.

[0061] FIG. 4 schematically illustrates a flowchart of an exemplary method 400 for steering of a heavy vehicle having an active suspension during steering system failure. The method is e.g. a computer-implemented method, and the various operations thereof may be performed by processing circuitry of a computer system, such as e.g. processing circuitry 210 of computer system 200, or similar.

[0062] As part of an operation S410, the method 400 includes to obtain the indication of an occurring or imminent failure of the ordinary steering system of the vehicle.

[0063] As part of an operation S420, the method 400 includes to, in response to obtaining the indication about the steering system failure, control the active suspension of the vehicle in accordance with the at least one particular sequence of vehicle roll angles, as part ofgenerating vehicle yaw moment to steer the vehicle using the active suspension instead of the ordinary steering system.

[0064] As generally used herein, that the active suspension is used for steering “instead of the ordinary steering system” also include the possibility of the ordinary steering system not having completely failed, but operating at a reduced level not sufficient to safely steer the vehicle to e.g. avoid collisions and / or safely bring the vehicle to a safe stop at e.g. a road side or similar.

[0065] FIG. 5 schematically illustrates a diagram of an exemplary computer system 150 for implementing examples disclosed herein, such as all or part of the control unit 150 and / or the computer system 200. 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 communicatively coupled 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.

[0066] 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 500may 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.

[0067] 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 described herein. 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.

[0068] 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.

[0069] 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 the processing 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.

[0070] 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 system500 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.

[0071] 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.

[0072] In summary of all of the above, the present disclosure improves upon currently available technology in that utilizes the active suspension of a vehicle to steer the vehicle in case of failure of the ordinary steering system of the vehicle, and optionally also uses the propulsion and / or braking system of the vehicle to further enhance such steering. This allows the vehicle to be brough to a safe stop, after e.g. first having performed one or more collision avoidance maneuvers (such as lane-lane changing and similar). The active suspension is controlled based on a sequence of vehicle roll angles that may in some examples be precomputed, in order to not having the computer system / control unit to calculate such sequences in a critical situation such as when in a failed steering system state. A decision to use a particular maneuver in order to handle the situation may e.g. be decided upon after first using one or more sensors of the vehicle, such as e.g. one or more cameras, radars, LIDARs, and similar, to confirm that the maneuver is safe, and that there are e.g. no objects blocking the execution of such a maneuver. Being able to bring the vehicle to a safe stop may be especially important for e.g. autonomous vehicles, and / or in situations wherein the time required before called-for help arrive is substantial and leaving the vehicle i.e. parked in the middle of a road is not deemed safe.

[0073] 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.

[0074] 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.

[0075] 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.

[0076] 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.

[0077] 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.

[0078] The following is an exemplifying list of examples envisaged herein:Example 1 : A computer system (150, 200, 500) for a heavy vehicle equipped with an active wheel suspension (230), the computer system including processing circuitry (210, 502) configured to: obtain an indication (220) of an occurring or imminent failure of an ordinary steering system (222) of the vehicle; in response to obtaining said indication, control (250) the active suspension of the vehicle in accordance with at least one particular sequence of vehicle roll angles, as part of generating vehicle yaw moment (Mz) to steer the vehicle using the active suspension instead of the ordinary steering system.Example 2: The computer system of example 1, wherein the processing circuitry is further configured to, as part of generating vehicle yaw moment, also control (260) a propulsion (262) of the vehicle.Example 3: The computer system of example 1 or 2, wherein the processing circuitry is further configured to, as part of generating vehicle yaw moment, use a map or model-based algorithm (240) indicating one or more yaw moments resulting from given vehicle roll angles.Example 4: The computer system of any one of examples 1 to 3, wherein the processing circuitry is further configured to determine the at least one particular sequence of vehicle roll angles from a set of one or more predetermined sequences of vehicle roll angles.Example 5: The computer system of any one of the preceding examples, wherein the processing circuitry is further configured to: obtain a warning (270) about an imminent risk of colliding with an object (360, 362) ahead of the vehicle, and determine the at least one particular sequence of vehicle roll angles as at least one sequence of vehicle roll angles suitable to avoid such collision with the object ahead.Example 6: The computer system of any one of the preceding examples, wherein the at least one particular sequence of vehicle roll angles is pertinent to a lane-changing maneuver (323, 325) for the vehicle.Example 7: The computer system of any one of the preceding examples, wherein the at least one particular sequence of vehicle roll angles is pertinent to a pull-to-curb or pull-to-side maneuver (320, 321, 326, 327) for the vehicle.Example 8: The computer system of any one of the preceding examples, wherein the processing circuitry is further configured to, as part of generating the vehicle yaw moment, control (290) also a braking system (292) of the vehicle.Example 9: The computer system of any one of the preceding examples, wherein the processing circuitry is further configured to obtain an indication of that an emergency or escape lane (350) is available ahead of the vehicle, and to determine the at least one particular sequence of vehicle roll angles as at least one sequence of vehicle roll angles suitable to steer (322) the vehicle into said emergency or escape lane.Example 10: The computer system of any one of the preceding examples, wherein the processing circuitry is further configured to obtain suspension capability information (282) pertaining to a current capability of the active suspension of the vehicle, and to control (250) the active suspension also based on the suspension capability information.Example 11 : The computer system of example 10, wherein the processing circuitry is further configured to both obtain the suspension control information and control the active suspension of the vehicle via a same suspension control / capability interface (280).Example 12: A heavy vehicle (100) including: an active wheel suspension (230), a steering system (162, 172, 222) for ordinary steering of the vehicle, and the computer system (150, 200, 500) of any one of examples 1 to 11.Example 13: The vehicle of example 12, wherein the active suspension is a gas-hydraulic wheel suspension and / or pneumatic wheel suspension.Example 14: A computer-implemented method (400) for steering of a heavy vehicle having an active wheel suspension during steering system failure, the method being performed by processing circuitry (210, 502) of a computer system (200, 500), the method including: obtaining (S410) an indication of an occurring or imminent failure of an ordinary steering system of the vehicle; in response to obtaining said indication, controlling (S420) the active suspension of the vehicle in accordance with at least one particular sequence of vehicle roll angles, as part of generating vehicle yaw moment to steer the vehicle using the active suspension instead of the ordinary steering system.Example 15: A computer program product (514) including program code (520) for performing, when executed by a processing circuitry (210, 502) of a computer system (200, 500), the method (400) of example 14.Example 16: A non-transitory computer-readable storage medium (514) including instructions (520), which when executed by a processing circuitry (210, 502) of a computer system (200, 500), cause the processing circuitry to perform the method (400) of example 14.

Claims

ClaimsWhat is claimed is:

1. A computer system (150, 200, 500) for a heavy vehicle equipped with an active wheel suspension (230), the computer system comprising processing circuitry (210, 502) configured to:- obtain an indication (220) of an occurring or imminent failure of an ordinary steering system (222) of the vehicle;- in response to obtaining said indication, control (250) the active suspension of the vehicle in accordance with at least one particular sequence of vehicle roll angles, as part of generating vehicle yaw moment (Mz) to steer the vehicle using the active suspension instead of the ordinary steering system.

2. The computer system of claim 1, wherein the processing circuitry is further configured to, as part of generating vehicle yaw moment, also control (260) a propulsion (262) of the vehicle.

3. The computer system of claim 1 or 2, wherein the processing circuitry is further configured to, as part of generating vehicle yaw moment, use a map or model-based algorithm (240) indicating one or more yaw moments resulting from given vehicle roll angles.

4. The computer system of any one of claims 1 to 3, wherein the processing circuitry is further configured to determine the at least one particular sequence of vehicle roll angles from a set of one or more predetermined sequences of vehicle roll angles.

5. The computer system of any one of the preceding claims, wherein the processing circuitry is further configured to:- obtain a warning (270) about an imminent risk of colliding with an object (360, 362) ahead of the vehicle, and- determine the at least one particular sequence of vehicle roll angles as at least one sequence of vehicle roll angles suitable to avoid such collision with the object ahead.

6. The computer system of any one of the preceding claims, wherein the at least one particular sequence of vehicle roll angles is pertinent to a lane-changing maneuver (323, 325) for the vehicle.

7. The computer system of any one of the preceding claims, wherein the at least one particular sequence of vehicle roll angles is pertinent to a pull-to-curb or pull-to-side maneuver (320, 321, 326, 327) for the vehicle.

8. The computer system of any one of the preceding claims, wherein the processing circuitry is further configured to, as part of generating the vehicle yaw moment, control (290) also a braking system (292) of the vehicle.

9. The computer system of any one of the preceding claims, wherein the processing circuitry is further configured to obtain an indication of that an emergency or escape lane (350) is available ahead of the vehicle, and to determine the at least one particular sequence of vehicle roll angles as at least one sequence of vehicle roll angles suitable to steer (322) the vehicle into said emergency or escape lane.

10. The computer system of any one of the preceding claims, wherein the processing circuitry is further configured to obtain suspension capability information (282) pertaining to a current capability of the active suspension of the vehicle, and to control (250) the active suspension also based on the suspension capability information.

11. The computer system of claim 10, wherein the processing circuitry is further configured to both obtain the suspension control information and control the active suspension of the vehicle via a same suspension control / capability interface (280).

12. A heavy vehicle (100) comprising:- an active wheel suspension (230),- a steering system (162, 172, 222) for ordinary steering of the vehicle, and- the computer system (150, 200, 500) of any one of claims 1 to 11.

13. The vehicle of claim 12, wherein the active suspension is a gas-hydraulic wheel suspension and / or pneumatic wheel suspension.

14. A computer-implemented method (400) for steering of a heavy vehicle having an active wheel suspension during steering system failure, the method being performed by processing circuitry (210, 502) of a computer system (200, 500), the method comprising:- obtaining (S410) an indication of an occurring or imminent failure of an ordinary steering system of the vehicle;- in response to obtaining said indication, controlling (S420) the active suspension of the vehicle in accordance with at least one particular sequence of vehicle roll angles, as part of generating vehicle yaw moment to steer the vehicle using the active suspension instead of the ordinary steering system.

15. A computer program product (514) comprising program code (520) for performing, when executed by a processing circuitry (210, 502) of a computer system (200, 500), the method (400) of claim 14.

16. A non-transitory computer-readable storage medium (514) comprising instructions (520), which when executed by a processing circuitry (210, 502) of a computer system (200, 500), cause the processing circuitry to perform the method (400) of claim 14.

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