WO2015094025A1

WO2015094025A1 - Control assembly for a vehicle

Info

Publication number: WO2015094025A1
Application number: PCT/SE2013/000198
Authority: WO
Inventors: Roland Kvist; Thomas Kvist
Original assignee: Volvo Construction Equipment Ab
Priority date: 2013-12-20
Filing date: 2013-12-20
Publication date: 2015-06-25
Also published as: GB201612573D0; GB2536841A

Abstract

The present disclosure relates to a control assembly (16) for a vehicle (10). The vehicle (10) has an extension along a longitudinal dimension (L) in the intended drive direction of the vehicle (10). The vehicle (10) comprises a front vehicle portion (12) and a rear vehicle portion (14). Moreover, the front and rear vehicle portions (12, 14) are connected to one another such that the front and rear vehicle portions (12, 14) can pivot relative to one another around a geometrical axis of rotation (AR) extending substantially along the longitudinal dimension (L). The control assembly (16) further comprises an active torque generator (18) adapted to selectively impart a torque around the geometrical axis of rotation (AR) between the front vehicle portion (12) and the rear vehicle portion (14).

Description

CONTROL ASSEMBLY FOR A VEHICLE

TECHNICAL FIELD

The present disclosure relates to a control assembly according to the preamble of claim 1. Moreover, the present disclosure relates to a vehicle. Further, the present disclosure relates to a method for controlling a vehicle.

BACKGROUND

A vehicle, for instance a working machine, may comprise a front vehicle portion and a rear vehicle portion. For instance, the front vehicle portion may be a tractor unit and the rear vehicle portion may be a trailer unit. An example of a working machine that comprises a front vehicle portion and a rear vehicle portion is an articulated hauler.

The rear vehicle portion may be adapted to carry load. The weight and/or position of the load may depend on e.g. the present application and/or load situation for the vehicle. Moreover, the vehicle may be adapted to travel upon various types of ground conditions and at various speeds.

The above combinations of e.g. loads, ground conditions and speeds may result in different types of conditions for at least a portion of the vehicle and some of these conditions may be less desired.

As a non-limiting example of an undesired condition, various vibrations may occur in the vehicle, such as in a driver's cabin thereof. As another non-limiting example of an undesired condition, if the vehicle is located on non-even ground, there may be a risk that e.g. one or more of the traction members, e.g. wheels, of the vehicle may lose contact with the ground.

SUMMARY

An object of the present disclosure is to provide a control assembly for a vehicle which may mitigate at least one of the undesired conditions discussed hereinabove. This object is achieved by a control assembly according to claim 1.

As such, the present disclosure relates to a control assembly for a vehicle. The vehicle has an extension in a longitudinal dimension in the intended drive direction of the vehicle. The vehicle comprises a front vehicle portion and a rear vehicle portion. The front and rear vehicle portions are connected to one another such that the front and rear vehicle portions can pivot relative to one another around a geometrical axis of rotation extending substantially in the longitudinal dimension. According to the present disclosure, the control assembly further comprises an active torque generator adapted to selectively impart a torque around the geometrical axis of rotation between the front vehicle portion and the rear vehicle portion.

The control assembly according to the above implies a versatile control of a vehicle.

As used herein, the expression "active torque generator" relates to a generator that is adapted to impart a torque to a system by adding energy to the system. As such, the "active torque generator" of the present disclosure is distinct from a damper which by definition dissipates energy from the system.

Optionally, the active torque generator comprises a first active torque generator portion that is adapted to be connected to the front vehicle portion and a second active torque generator portion that is adapted to be connected to the rear vehicle portion. Optionally, one of the first and second active torque generator portions comprises a stator and the other one of the first and second active torque generator portions comprises a rotor. As such, the active torque generator may comprise an electric motor one component of which is associated with the front vehicle portion and another portion of which is associated with the rear vehicle portion.

Optionally, the active torque generator is adapted to selectively impart a torque around the geometrical axis of rotation directly on a shaft of one of the front vehicle portion and the rear vehicle portion. As used herein, the expression "shaft" relates to a member that is fixedly attached to the front vehicle portion or the rear vehicle portion. This implies a rapid response for the active torque generator. Optionally, the vehicle comprises a powertrain adapted to generate motive power. The active torque generator is adapted to selectively impart the torque such that a set of different torque magnitudes can be obtained for a specific magnitude of motive power generated by the powertrain. The possibility to obtain a plurality of different torque magnitudes implies a versatile torque application.

Optionally, the control assembly is adapted to determine a condition value indicative of a condition of a portion of the vehicle. The active torque generator is adapted to selectively impart a torque around the geometrical axis of rotation between the front vehicle portion and the rear vehicle portion such that the condition of the portion of the vehicle corresponds to a new condition value within a condition threshold range.

Optionally, the condition value is indicative of an occurring or imminent position change of a portion of the front vehicle portion. For instance, the position change may be in a position change direction having a component that is perpendicular to the longitudinal dimension. As such, the position change value may be different from the speed of the vehicle. Optionally, the condition value is indicative of an occurring or imminent velocity and/or acceleration of the portion of the vehicle.

Optionally, the front vehicle portion comprises a driver's seat, the condition value comprising information indicative of the acceleration of the driver's seat. As such, the active torque generator may be used for improving the working environment for the driver of the vehicle.

Optionally, the control assembly is adapted to determine an operating state, the control assembly further being adapted to determine the position change threshold range based on the operating state. The above implies that the tolerance of the control of the condition of a portion of the vehicle may be made dependent on the operating state.

Optionally, the operating state comprises information indicative of at least one of the following parameters: the velocity of the vehicle, the mass of at least one of the front and rear vehicle portions, the angular velocity of the pivoting of the rear vehicle portion relative to the front vehicle portion, the angular acceleration of the pivoting of the rear vehicle portion relative to the front vehicle portion and the position of the rear vehicle portion relative to the front vehicle portion. A second aspect of the present disclosure relates to a vehicle comprising a control assembly according to the first aspect of the present disclosure.

A third aspect of the present disclosure relates to a method for controlling a vehicle. The vehicle has an extension in a longitudinal dimension in the intended drive direction of the vehicle. The vehicle comprises a front vehicle portion and a rear vehicle portion. The front and rear vehicle portions are connected to one another such that the first and rear vehicle portions can pivot relative to one another around a first axis of rotation extending substantially in the longitudinal dimension. The vehicle comprises an active torque generator adapted to selectively impart a torque around the first axis of rotation between the front vehicle portion and the rear vehicle portion.

The method comprises:

- determining a condition value indicative of a condition of a portion of said vehicle, and

- using said active torque generator to selectively impart a torque between said front vehicle portion and said rear vehicle portion around said first axis of rotation such that the condition of said portion of said vehicle corresponds to a new condition value within a condition threshold range. Optionally, the condition value may be a position change value indicative of an occurring or imminent position change, for instance in a position change direction having a component that is perpendicular to the longitudinal dimension, of a portion of the vehicle.

A fourth aspect of the present disclosure relates to a computer program comprising program code means for performing the steps of the third aspect of the present disclosure when the program is run on a computer.

A fifth aspect of the present disclosure relates to a computer readable medium carrying a computer program comprising program code means for performing the steps of the third aspect of the present disclosure when the program code means is run on a computer. BRIEF DESCRIPTION OF THE DRAWINGS

With reference to the appended drawings, below follows a more detailed description of embodiments of the invention cited as examples.

In the drawings: Fig. 1 illustrates a vehicle; Fig. 2 illustrates an implementation of an active torque generator; Fig. 3 illustrates another implementation of an active torque generator; Fig. 4 is a flow chart of a method for controlling a vehicle; Fig. 5 illustrates a vehicle on a slope, and

Fig. 6 illustrates a vehicle in the Fig. 5 condition, but with an applied torque. It should be noted that the appended drawings are not necessarily drawn to scale and that the dimensions of some features of the present invention may have been exaggerated for the sake of clarity.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

The invention will be described in the following for a vehicle in the form of an articulated hauler 10 such as the one illustrated in Fig. 1. The articulated hauler 10 should be seen as an example of a vehicle which could comprise a control assembly according to the present invention. However, the transmission assembly of the present invention may be implemented in a plurality of different types of objects, e.g. other types of vehicles. Purely by way of example, the control assembly could be implemented in a working machine such as a wheel loader, a dumper truck, or any other type of construction equipment.

As is indicated in Fig. 1 , the vehicle 10 has an extension in a longitudinal dimension L in the intended drive direction of the vehicle. The vehicle 10 comprises a front vehicle portion 12 and a rear vehicle portion 14. The front and rear vehicle portions 12, 14 are connected to one another such that the front and rear vehicle portions can pivot relative to one another around a geometrical axis of rotation A_R extending substantially along the longitudinal dimension L. As such, when the vehicle 10 is located on horizontal ground, the longitudinal dimension L, and consequently also the geometrical axis of rotation A_Ri may be substantially horizontal.

Moreover, the front and rear vehicle portions 2, 14 are preferably connected to one another such that the front and rear vehicle portions can pivot relative to one another around a steering axis A_s extending substantially in the vertical dimension V. Preferably, and as is indicated in the Fig. 1 embodiment, the vehicle 10 is a frame-steered vehicle which comprises one or more actuators (not shown) for changing the pivot angle around the steering axis A_s to thereby steer the vehicle 10. Purely by way of example, the one or more actuators may comprise a hydraulic actuator, e.g. a hydraulic cylinder, and/or an electric actuator.

Fig. 1 further illustrates that the vehicle 10 comprises a control assembly 16. The control assembly 16 comprises an active torque generator 8 adapted to selectively impart a torque around the geometrical axis of rotation A_R between the front vehicle portion 12 and the rear vehicle portion 14.

The vehicle 10 comprises a powertrain 15 adapted to generate motive power. The active torque generator 18 is preferably adapted to selectively impart the torque such that a set of different torque magnitudes can be obtained for a specific magnitude of motive power generated by the powertrain 15. As such, the magnitude of the imparted torque is not necessarily proportional to the magnitude of motive power generated by the powertrain 15.

The control assembly 16 may be adapted to determine a condition value indicative of a condition of a portion of the vehicle 10. The active torque generator 18 is preferably adapted to selectively impart a torque around the geometrical axis of rotation A_R between the front vehicle portion 12 and the rear vehicle portion 14 such that the condition of the portion of the vehicle 10 corresponds to a new condition value within a condition threshold range. As a non-limiting example, the control assembly may be adapted to determine a condition value indicative of an occurring or imminent position change, for instance in a position change direction having a component that is perpendicular to the longitudinal dimension, of a portion of the vehicle 10. The active torque generator 18 may preferably be adapted to selectively impart a torque around the geometrical axis of rotation A_R between the front vehicle portion 12 and the rear vehicle portion 14 such that an occurring or imminent position change of the portion of the vehicle 10 corresponds to a position change value within a position change threshold range. Purely by way of example, the condition value may be indicative of an occurring or imminent position change of a portion of the front vehicle portion. Alternatively, or in addition, the position change value may be indicative of an occurring or imminent velocity and/or acceleration of a portion, such as the front portion, of the vehicle. As another example, the front vehicle portion comprises a driver's seat and the position change value comprises information indicative of the acceleration of the driver's seat 17. Purely by way of example, the position change value may comprise information indicative of the acceleration in one or more directions of the driver's seat 17. To this end, the control assembly 16 may comprise a driver's seat sensor 19 that is adapted to determine e.g. the acceleration along one or more of the longitudinal dimension L, the transversal dimension T or the vertical dimension V in at least a portion of the driver's seat 7. Purely by way of example, the control assembly 16 may comprise an electronic control unit 21 that is in communication with the driver's seat sensor 19, and/or any other sensor for determining a condition value, as well as the active torque generator 18.

Generally, at least in the example wherein the vehicle 10 is an articulated hauler, the mass of the rear vehicle portion 14 is generally greater than the front vehicle portion 12. In such an example, the mass of the rear vehicle portion 14 may be utilized for dampening the motions of the front vehicle portion 12 by imparting a torque between the front and rear vehicle portions 12, 14 using the active torque generator 18.

Further, the control assembly 16 may comprise one or more other sensors 23 adapted to determine e.g. one or more dynamic and/or static parameters of at least a portion of the vehicle 10. As non-limiting examples, such parameters may comprise: the speed of the vehicle, the acceleration of the rotation around the geometrical axis of rotation A_R, the speed of the rotation around the geometrical axis of rotation A_R, the mass and/or position of at least a portion of the vehicle 10 or a value indicative of the slope of the ground beneath the vehicle 10. Moreover, the control assembly may be adapted to determine an operating state. The control assembly may be adapted to determine the operating condition threshold range based on the operating state. As a non-limiting example, the operating state may be indicative of the type of condition that the vehicle 10 currently is in, such as a loading condition, an off-loading condition, a loaded transport condition or an unloaded transport condition.

Further, the operating state may comprise information indicative of at least one of the following parameters: the velocity of the vehicle 10, the mass of at least one of the front and rear vehicle portions 12, 14, the angular velocity of the pivoting of the rear vehicle portion 14 relative to the front vehicle portion 12, the angular acceleration of the pivoting of the rear vehicle portion 14 relative to the front vehicle portion 12 and the position of the rear vehicle portion 14 relative to the front vehicle portion 12.

As such, the operating condition threshold range, and consequently the tolerance by which the control assembly 16 operates, may be changed depending on the operating state. As a non-limiting example, if the condition value is indicative of an acceleration in the driver's seat 17 and the operating state is indicative of the velocity of the vehicle 10, the operating condition threshold range, and thus the tolerance of the control of the acceleration in the driver's seat 17, may be selected so as to increase with an increased velocity of the vehicle 10.

Moreover, the vehicle 10 generally extends along a transversal dimension T extending substantially perpendicularly to the longitudinal dimension. The vehicle comprises at least one wheel located at a transversal distance, i.e. a distance along the transversal dimension T, from the first axis of rotation A_R. The active torque generator is adapted to impart a load to the wheel. As a non-limiting example, the active torque generator 18 may be adapted to impart a load to the wheel in the vertical dimension V.

Fig. 2 illustrates an implementation of the active torque generator 18. As may be gleaned from Fig. 2, the active torque generator 18 illustrated therein comprises a first active torque generator portion 20 that is adapted to be connected to the front vehicle portion (not shown in Fig. 2) and a second active torque generator portion 22 that is adapted to be connected to the rear vehicle portion (not shown in Fig. 2). The implementation of the active torque generator 18 illustrated in Fig. 2 comprises an electric motor.

5

Purely by way of example, and as is indicated in Fig. 2, the first active torque generator portion 20 may be connected to, or even form part of, a pivotable joint pin 24. The pivotable joint pin 24 may for instance be adapted to house a bearing pin (not shown) which may be substantially vertically extending in order to allow the pivotable joint pin 24 10 to be pivoted around the steering axis A_s. The second active torque generator portion 22 may be connected, for instance fixedly connected, to a rear vehicle section 26, e.g. a shaft, which in turn may form part of, or may be connected to, the rear vehicle portion 14.

As a non-limiting example, one of the first and second active torque generator portions 20, 15 22 comprises a stator and the other one of the first and second active torque generator portions 20, 22 comprises a rotor. In the implementation illustrated in Fig. 2, the pivotable joint pin 24 comprises the rotor 28 whereas second active torque generator portion 22 comprises the stator 30.

20 Purely by way of example, the rotor 28 may be connected to the pivotable joint pin 24. In the implementation of the active torque generator 18 illustrated in Fig. 2, the rotor 28 forms part of the pivotable joint pin 24. As a non-limiting example, the rotor 28 may comprise a magnetic portion which may be a permanent magnet and/or an electromagnet. In a similar vein, the stator 30 may comprise a magnetic portion which may be a

25 permanent magnet and/or an electromagnet. Preferably, at least one of the rotor 28 and the stator 30 comprises an electromagnet.

Purely by way of example, the active torque generator 18 may be such that an air gap Δ is obtained between the rotor 28 and the stator 30. As a non-limiting example, the air gap Δ 0 is circumferentially extending between the rotor 28 and the stator 30 and the air gap Δ may be within the range of 0.01 to 1 mm.

Purely by way of example, the active torque generator 18 may comprise a retention assembly 32 for limiting, preferably preventing, relative displacement between the rotor 28 and the stator 30 in at least one direction along the longitudinal dimension L and/or the vertical dimension V.

In the implementation of the active torque generator 18 illustrated in Fig. 2, the retention assembly 32 comprises a flange 34 that may be connected, directly or indirectly, to the rotor 28. Moreover, the flange 34 may be adapted to, directly or indirectly, abut an abutment surface 38 that is connected, directly or indirectly, to the stator 30. In the Fig. 2 implementation, the flange 34 is connected to the pivotable joint pin 24 by means of a joint 36. The joint 36 may comprise a weld joint, glue joint or the like. However, in the implementation illustrated in Fig. 2, the joint 36 comprises a bolt joint.

As such, the flange 34 and the abutment surface 38 may limit the relative displacement of the rotor 28 and the stator 30 in at least one direction in the longitudinal dimension L but allow a rotation of the rotor 28 relative to the stator 30. To this end, though purely by way of example, the retention assembly 32 may comprise a bearing assembly (not shown) which is located between the flange 34 and the abutment surface 38. As another non- limiting example, the retention assembly may comprise a lubricant that is accommodated between the flange 34 and the abutment surface 38. Moreover, it is also envisaged that implementations of the retention assembly 32 comprise a second flange 40 and a second abutment surface 42 that may limit the relative displacement of the rotor 28 and the stator 30 in least the other direction in the

longitudinal dimension L but allow a rotation of the rotor 28 relative to the stator 30. Purely by way of example, and as is indicated in Fig. 2, the second flange 40 and the second abutment surface 42 may be located on the opposite side of the rotor 28 and/or stator 30 in the longitudinal dimension L, as compared to the first flange 34 and the first abutment surface 38.

Fig. 3 illustrates another implementation of the active torque generator 18. As compared to the Fig. 2 active torque generator 18, the Fig. 3 torque generator instead comprises a fluid motor 44. Purely by way of example, and as is indicated in Fig. 3, the fluid motor 44 may comprise a sealed cavity 46 that is formed between the pivotable joint pin 24 and the rear vehicle section 26. Moreover, the fluid motor 44 may comprise a plurality of blades 48 that are connected to the pivotable joint pin 24 and located within the cavity 46. Preferably, at least one of the blades 48 extends at least partially along the longitudinal dimension L. Further, the fluid motor 44 may comprise pressurized medium supply assembly 50 adapted to supply pressurized medium, such as a fluid, for instance air or oil, to the cavity 46. When pressurized medium is supplied to the cavity 46, a torque around the geometrical axis of rotation A_R may be generated.

Purely by way of example, the pressurized medium supply assembly 50 may comprise a pressure source 52, for instance a pump, and a conduit assembly 54 adapted to provide fluid communication between the pressure source 52 and the cavity 46. The conduit assembly 54 may comprise one or more conduits, such as an inlet conduit and an outlet conduit, although the conduit assembly 54 is illustrated by one single line in Fig. 3. In order to be able to vary the magnitude and/or the direction of the thereby imparted torque, the fluid motor 44 preferably has the capability to change the pressure level and/or direction of flow in the cavity 46. As a non-limiting example, the pressurized medium supply assembly 50 may be adapted to supply positive as well as negative pressures to the cavity 46.

Instead of, or in addition to, the electric motor or the fluid motor that have been discussed hereinabove, the type of active torque generator 18 may for instance comprise an actuator (not shown), for instance a linear actuator, that is adapted to impart a torque around the geometrical axis of rotation A_R.

Irrespective of the type of active torque generator 18 that is used, and purely by way of example, the active torque generator 18 may be adapted to selectively impart a torque around the geometrical axis of rotation A_R directly on a shaft of one of the front vehicle portion and the rear vehicle portion.

Moreover, irrespective of the implementation of the active torque generator 18 that is used, the active torque generator 18 may be used in a method according to the present invention for controlling a vehicle 10. As such, and with reference to Fig. 4, the method comprises: 54 determining a condition value indicative of a condition of a portion of the vehicle 0, and 56 using said active torque generator 18 to selectively impart a torque between said front vehicle portion 12 and said rear vehicle portion 14 around said first axis of rotation such that the condition of said portion of said vehicle corresponds to a new condition value within a condition threshold range. As has previously been indicated, the condition threshold range may be determined based on an operating state such as the speed or mass of the vehicle 10.

As may be gleaned from Fig. 4, the method according to the present invention may use an iterative process wherein 58 the new condition value is determined after, or during, imparting a torque and that 60 the new condition value thus determined is compared to the condition threshold range, which may be a predetermined condition threshold range. If the new condition value is within the condition threshold range, the iterative process is terminated, otherwise the iterative process continues until a new condition value within the condition threshold range is obtained.

As a non-limiting example, the condition value may be a position change value indicative of an occurring or imminent position change, for instance in a position change direction having a component that is perpendicular to the longitudinal dimension, of a portion of the vehicle.

It should be noted that the condition value may also, or instead, be indicative of a static condition. To this end, reference is made to Fig. 5 wherein the condition value is indicative of the difference in normal forces between the wheels of a vehicle. In Fig. 5, only the rear vehicle portion 14 of the vehicle 10 is visible. The vehicle 10 may be in a stationary condition, e.g. a loading or off-loading condition, or a dynamic condition, e.g. a forward driving condition.

As may be gleaned from Fig. 5, the vehicle 10 rests on a slope with an angle a resulting in that the normal force acting on the left set of wheels 3 of the rear vehicle portion 14 may be substantially smaller than the normal force N₂ acting on the right set of wheels 13. As such, there is a risk that the left set of wheels may slip as the vehicle 10 moves or begins to move. Alternatively, there is a risk that the normal force N_! acting on the left set of wheels 13 is reduced to a small amount which may imply an increased risk that the rear vehicle portion 14 is more prone to roll over.

In order to reduce the differences in normal forces N₂ , the active torque generator 18 may be used to impart a torque T_imp around the geometrical axis of rotation A_R between the front vehicle portion (not shown in Fig. 5 or Fig. 6) and said rear vehicle portion 16. The torque imparted T_imp has a direction such that the rear vehicle portion 14 is imparted a torque in a counter-clockwise direction. Such a condition is indicated in Fig. 6. As may be gleaned when comparing the conditions in Fig. 5 and Fig. 6, respectively, the differences in the normal forces N₂ is smaller in the Fig. 6 condition as compared to the Fig. 5 condition which implies that the Fig. 6 condition may be preferred from e.g. a drivability and/or a safety point of view.

As such, in the Fig. 5 and Fig. 6 example, the condition value is indicative of the difference in the normal forces N₂ and the condition threshold range is indicative of an acceptable difference in the normal forces N₂. Purely by way of example, the magnitude of such a condition threshold range may be made dependent on the angle a of the slope.

It should be noted that the method may use a plurality of different condition values based on e.g. data from sensors determining dynamic and/or static parameters of at least a portion of the vehicle 10 using e.g. any one of the sensors that have been discussed hereinabove with reference to Fig. 1.

Finally, it should be recognized that structures and/or elements and/or method steps shown and/or described in connection with any disclosed form or embodiment of the invention may be incorporated in any other disclosed or described or suggested form or embodiment as a general matter of design choice. It is the intention, therefore, to be limited only as indicated by the scope of the claims appended hereto.

Claims

1. A control assembly (16) for a vehicle (10), said vehicle (10) having an extension along a longitudinal dimension (L) in the intended drive direction of said vehicle (10), said vehicle (10) comprising a front vehicle portion (12) and a rear vehicle portion (14), said front and rear vehicle portion (12, 14) being connected to one another such that said front and rear vehicle portions (12, 14) can pivot relative to one another around a geometrical axis of rotation (A_R) extending substantially along said longitudinal dimension (L),

c h a ra cte r i ze d i n t h at said control assembly (16) further comprises an active torque generator (18) adapted to selectively impart a torque around said geometrical axis of rotation (A_R) between said front vehicle portion (12) and said rear vehicle portion (14).

The control assembly (16) according to claim 1 , wherein said active torque generator (18) comprises a first active torque generator portion (20) that is adapted to be connected to said front vehicle portion (12) and a second active torque generator portion (22) that is adapted to be connected to said rear vehicle portion (14).

The control assembly (16) according to claim 2, wherein one of said first and second active torque generator portions (20, 22) comprises a stator (30) and the other one of said first and second active torque generator portions (20, 22) comprises a rotor (28).

The control assembly (16) according to any one of the preceding claims, wherein said active torque generator (18) is adapted to selectively impart a torque around said geometrical axis of rotation directly on a shaft of one of said front vehicle portion ( 2) and said rear vehicle portion (14).

The control assembly (16) according to any one of the preceding claims, wherein said vehicle comprises a powertrain (15) adapted to generate motive power, said active torque generator (18) being adapted to selectively impart said torque such that a set of different torque magnitudes can be obtained for a specific magnitude of motive power generated by said powertrain (15).

6. The control assembly (16) according to any one of the preceding claims, wherein said control assembly (16) is adapted to determine a condition value indicative of a condition of a portion of said vehicle, said active torque generator (18) being adapted to selectively impart a torque around said geometrical axis of rotation between said front vehicle portion (12) and said rear vehicle portion (14) such that the condition of said portion of said vehicle corresponds to a new condition value within a condition threshold range.

7. The control assembly (16) according to claim 6, wherein said condition value is indicative of an occurring or imminent position change of a portion of said front vehicle portion (12).

8. The control assembly (16) according to claim 6 or 7, wherein said condition value is indicative of an occurring or imminent velocity and/or acceleration of said portion of said vehicle.

9. The control assembly (16) according to claim 8, wherein said front vehicle portion (12) comprises a driver's seat (17), said condition value comprising information indicative of the acceleration of said driver's seat.

10. The control assembly (16) according to any one of claims 6 to 9, wherein said control assembly (16) is adapted to determine an operating state, said control assembly (16) further being adapted to determine said position change threshold range based on said operating state.

11. The control assembly (16) according to claim 10, wherein said operating state comprises information indicative of at least one of the following parameters: the velocity of the vehicle, the mass of at least one of said front and rear vehicle portions (14), the angular velocity of the pivoting of said rear vehicle portion (14) relative to said front vehicle portion (12), the angular acceleration of the pivoting of said rear vehicle portion (14) relative to said front vehicle portion (12) and the position of said rear vehicle portion (14) relative to said front vehicle portion (12).

12. A vehicle comprising a control assembly (16) according to any one of the

preceding claims.

A method for controlling a vehicle, said vehicle having an extension along a longitudinal dimension (L) in the intended drive direction of the vehicle, said vehicle comprising a front vehicle portion (12) and a rear vehicle portion (14), said front and rear vehicle portions (14) being connected to one another such that said first and rear vehicle portions (14) can pivot relative to one another around a first axis of rotation extending substantially in said longitudinal dimension, said vehicle comprising an active torque generator (18) adapted to selectively impart a torque around said first axis of rotation between said front vehicle portion (12) and said rear vehicle portion (14), said method comprising:

- using said active torque generator (18) to selectively impart a torque

between said front vehicle portion (12) and said rear vehicle portion

(14) around said first axis of rotation such that the condition of said portion of said vehicle corresponds to a new condition value within a condition threshold range.

A computer program comprising program code means for performing the steps of claim 13 when said program is run on a computer.

15. A computer readable medium carrying a computer program comprising program code means for performing the steps of claim 13 when said program code means is run on a computer.