METHOD FOR OPERATING A SOIL CULTIVATION MACHINE

Description

[0001] The present invention relates to a method for operating a soil cultivation machine, such as a soil compactor.

[0002] German patent application DE 10 2019 127 640 A1 discloses a method for operating a soil compactor-type tillage machine in which a maximum steering angle, with which the machine can be steered in a curve, is predetermined depending on the machine's travel speed. As the travel speed increases, the maximum steering angle, i.e., the maximum extent to which the machine can be steered, is reduced. This prevents the machine from tipping over if it is turned too sharply at high speed.Furthermore, excessively uneven loading caused by centrifugal forces occurring in a curve steering state, which a roller unit of such a soil cultivation machine exerts on the soil to be cultivated, for example to be compacted, in its inner and outer curve areas, is avoided, thereby also preventing uneven soil cultivation behavior in the direction of a roller rotation axis.

[0003] A method for operating a soil cultivation machine according to the preamble of claim 1 is known from CN 113 152 215 A. In this method, a steering angle and a travel speed of the soil cultivation machine are detected. Furthermore, the distance of the front and rear sections of the soil cultivation machine to an edge of the soil to be cultivated are detected by means of a plurality of non-contact distance sensors and a plurality of contact distance sensors, and thus the angle at which the soil cultivation machine approaches or moves away from the edge is determined. When the soil cultivation machine approaches the edge and when it moves away from the edge, the steering angle and the speed of the soil cultivation machine are adjusted so that the angle at which the soil cultivation machine approaches or moves away from the edge is determined.moving away from this corresponds to a target approach angle or a target distance angle.

[0004] The object of the present invention is to provide a method for operating a soil cultivation machine, such as a soil compactor, which achieves high efficiency in soil cultivation while increasing operational reliability.

[0005] According to the invention, this problem is solved by a method for operating a soil cultivation machine, wherein the soil cultivation machine comprises two roller units arranged at a distance from each other in a longitudinal direction of the machine, wherein each of the two roller units is rotatable about a roller axis of rotation, wherein the two roller units are pivotable relative to each other for steering the soil cultivation machine, wherein in a straight-ahead steering state corresponding to a steering state of the soil cultivation machine with a minimum steering range, the roller axes of rotation of the two roller units are oriented substantially parallel to each other, and in a curve steering state corresponding to a steering state of the soil cultivation machine with a steering range that differs from the minimum steering range, the roller axes of rotation of the two roller units have an orientation relative to each other that deviates from a parallel orientation.the procedure includes the following measures: , a) Providing a steering angle-speed relationship that reflects a maximum permissible driving speed depending on the steering angle, b) Recording the actual steering angle of the tillage machine, c) Setting the driving speed of the tillage machine such that the driving speed does not exceed the maximum permissible driving speed assigned to the actual steering angle recorded in measure b) according to the steering angle-speed relationship provided in measure a).

[0006] In contrast to the prior art, the method according to the invention uses the steering angle, rather than the travel speed of a soil cultivation machine, as the guiding parameter. This means that, regardless of the travel speed, a soil cultivation machine operated in this way can be steered to any extent up to its maximum possible steering angle. A potentially safety-critical situation, in which such a soil cultivation machine is intended to be steered into a specific area of ​​the soil to be cultivated, but this is not possible due to a speed-dependent limitation of the steering angle, while an operator expects the machine to be able to move into this area and, for example, past an obstacle, cannot therefore occur.

[0007] Furthermore, the method according to the invention allows the maximum possible steering range of such a soil cultivation machine to be utilized at any time, regardless of the driving speed, so that every area of ​​the soil to be cultivated that can be reached with the maximum steering range can also be traversed. It is not necessary to make multiple additional passes due to a limitation of the steering range in order to move the soil cultivation machine into an area of ​​the soil to be cultivated that could be reached with a single pass or a smaller number of passes without such a limitation.

[0008] If, during the operation of a soil cultivation machine, a state is reached in which the driving speed exceeds the maximum permissible driving speed associated with the actual steering dimension of the soil cultivation machine, the driving speed can, according to the invention, be reduced in measure c) such that the driving speed essentially corresponds to the maximum permissible driving speed associated with the actual steering dimension.

[0009] If the tillage machine returns to a steering state that does not require a previously specified speed limit, or no longer requires it to the extent previously imposed, it may be provided that, after reducing the speed to the maximum permissible speed associated with the actual steering range of the tillage machine, the steering state is changed towards a steering state with a smaller steering range: The driving speed is increased to the maximum permissible driving speed associated with the steering state with a smaller steering range if the driving speed existing before the reduction in driving speed is higher than the maximum permissible driving speed associated with the steering state with a smaller steering range, or the driving speed is increased to the driving speed existing before the reduction in driving speed if the driving speed existing before the reduction in driving speed is lower than the maximum permissible driving speed associated with the steering state with a smaller steering range.

[0010] In a procedure that is easy to implement and does not require operator interaction, the driving speed can be automatically increased to the maximum permissible driving speed associated with the steering state with the smaller steering range, or to the driving speed present before the reduction in driving speed, when the steering state changes towards the steering state with a smaller steering range.

[0011] Alternatively, it can be provided that when the steering input changes towards a steering input with a smaller steering angle, the vehicle speed is only increased to the maximum permissible speed associated with the steering input with the smaller steering angle, or to the speed present before the reduction in speed, if a speed increase confirmation is present. Such a speed increase confirmation can be generated, for example, by the operator manipulating a designated confirmation device, such as a switch or the like, so that an increase in vehicle speed only occurs when the operator permits it and therefore the operator cannot be surprised by a sudden increase in speed.

[0012] If the driving speed of the soil cultivation machine is to be increased from a driving speed below the maximum permissible driving speed associated with the actual steering adjustment to a target driving speed above the maximum permissible driving speed associated with the actual steering adjustment, the driving speed of the soil cultivation machine can be increased in such a way as to essentially correspond to the maximum permissible driving speed associated with the actual steering adjustment, so that the basically specified target driving speed is not initially reached, in order to avoid an excessively high driving speed in measure c).

[0013] If, after increasing the driving speed to the maximum permissible driving speed associated with the current steering angle, the steering state changes towards a steering state with a smaller steering angle: Can the driving speed be increased to essentially correspond to the maximum permissible driving speed associated with the steering state with a smaller steering range if the target driving speed is higher than the maximum permissible driving speed associated with the steering state with a smaller steering range, or can the driving speed be increased to essentially correspond to the target driving speed if the target driving speed is lower than the maximum permissible driving speed associated with the steering state with a smaller steering range?

[0014] Even when returning to a steering state with a smaller steering range, the driving speed can be automatically increased to the maximum permissible driving speed or the target driving speed associated with the steering state with a smaller steering range if the steering state changes in the direction of the steering state with a smaller steering range.

[0015] Alternatively, to increase operational safety, the driving speed can only be increased to the maximum permissible driving speed associated with the steering state with the smaller steering range or the target driving speed if a speed increase confirmation is present.

[0016] In a simple design example of the steering angle-driving speed relationship that ensures high operational reliability, the maximum permissible driving speed can decrease essentially linearly with increasing steering angle, at least in one range of driving speed.

[0017] A restriction of the driving speed in a condition where this is not actually necessary can be avoided by ensuring that, when the steering angle is below a threshold steering angle, the maximum permissible driving speed corresponds to the maximum possible driving speed of the soil cultivation machine.

[0018] Since even at comparatively low driving speeds there is essentially no risk of tipping over or uneven loading of the soil being worked by a roller unit, it can further be provided that at driving speeds below a threshold driving speed, no change in driving speed dependent on a steering dimension takes place.

[0019] The steering angle can be determined, for example, based on the position of at least one steering actuator. Such a steering actuator can be designed, for instance, as a piston / cylinder unit that acts between the machine frame of a tillage machine and a roller frame pivotally mounted on it, which in turn rotatably supports a roller unit. The position of such a steering actuator can be detected, and this information can be used to determine the steering angle. Alternatively or additionally, the steering angle can be determined based on the actuation of a steering control device, such as a steering wheel or a joystick. This actuation can also be detected by means of appropriate sensors, and this information can be used to determine the steering angle.

[0020] The travel speed can be determined, for example, based on the rotational speed of at least one of the roller units. Alternatively or additionally, the travel speed can be determined based on the position of a hydraulic drive system for at least one of the roller units. Such a hydraulic drive system generally comprises one or more hydraulic pumps and, assigned to each driven roller unit, at least one hydraulic motor. The hydraulic motor and / or the hydraulic pump supplying it can operate with variable displacement or variable flow rate to adjust the amount of circulating fluid used to determine the travel speed. The position of such a hydraulic motor or pump, or the flow rate of the fluid flowing through it, is thus linked to the travel speed of a tillage machine.In another variant, the travel speed can be determined based on the position of a drive control device. As long as no control intervention to reduce the travel speed is present, there is a substantially unambiguous relationship between the position of a drive control device, for example, a drive lever operated by a person, and the travel speed of a tillage machine. However, the position of such a drive control device can be considered a parameter representing a target travel speed actually specified by the operator, particularly when an intervention to reduce the travel speed has occurred. In a further option for determining the travel speed, it can be determined based on position information provided by a position detection system.Such a positioning system can be satellite-based, for example, GPS. By determining changes in the position of a tillage machine, its speed can be inferred from the position information.

[0021] The present invention is described in detail below with reference to the accompanying figures. These show: Fig. 1 a side view of a soil cultivation machine designed as a soil compactor; Fig. 2 a schematic representation of a soil cultivation machine in a curve steering state; Fig. 3 a steering degree-travel speed diagram showing a steering degree-travel speed relationship.

[0022] In Fig. 1 A soil cultivation machine designed as a soil compactor is generally designated by 10. The soil cultivation machine 10 comprises a roller unit 14, designed as a compaction roller in the illustrated example, on a rear carriage 12, and a roller unit 18, also designed as a compaction roller, on a front carriage 16. Each of the roller units 14, 18 is rotatably mounted about an associated roller axis of rotation on the rear carriage 12 and the front carriage 16, respectively. For example, each of the roller units 14, 18 can be driven to rotate about its respective associated roller axis of rotation.

[0023] In the illustrated embodiment, each of the roller units 14, 18 is designed with a roller shell constructed of steel material. In an alternative embodiment, one or both roller units 14, 18 could be divided in the direction of the respective roller axis of rotation or could comprise a plurality of rubber wheels successively in the direction of the roller axis of rotation.

[0024] The rear carriage 12 and the front carriage 16 are pivotally connected to each other about a steering axis A in the area of ​​an articulated joint 20. The steering axis A can be oriented essentially orthogonally to the ground 22 on which the tillage machine 10 moves, but can also have an angular position relative to the ground 22 that deviates from an orthogonal orientation and / or changes during a steering operation.

[0025] A control station, generally designated 24, for an operator is provided on the rear carriage 12. A seat 26 for the operator is arranged on the control station 24. Furthermore, a steering actuation element 28, designed as a steering wheel in the illustrated example, is provided on the control station 24. Actuation of the steering actuation element 28 activates a steering system that pivots the front carriage 16 relative to the rear carriage 12, so that, starting from a straight-ahead driving condition in which the axes of rotation of the two roller units 14, 18 are essentially parallel to each other, the rear carriage 12 and the front carriage 16 are angled relative to each other, and accordingly, the axes of rotation of the two roller units 14, 18 also come into an angled position relative to each other.

[0026] At the operator station 24, a drive control device 30, designed, for example, as a drive lever, is also provided. By pivoting the drive control device 30, an operator can specify a speed at which the soil cultivation machine 10 is moved over the soil 22 to be cultivated. Depending on the degree of actuation of the drive control device 30, a generally hydraulically operated drive system is activated to drive one or both of the roller units 14, 18 to rotate about their respective roller axis of rotation.

[0027] The tillage machine 10 further comprises a control unit generally designated 32. The control unit 32 receives, for example, information about the degree of actuation of the steering control device 28 and about the degree of actuation of the drive control device 30 and controls the corresponding system areas, i.e., a steering system and a drive system respectively, according to the respective degree of actuation detected, in order to move the tillage machine 10 at the speed specified by an operator in the direction specified by the operator.The control unit 32 can include one or more programmable microprocessors which, by processing stored control programs and taking into account various parameters, such as a driving speed or a steering dimension, control various system areas of the soil cultivation machine 10 in order to carry out a soil cultivation operation intended for this machine.

[0028] In Fig. 2 A soil cultivation machine 10 of this type is depicted in a basic manner. The rear carriage 14, extending along a longitudinal axis LH, is visible. The roller unit 14 is rotatably mounted on this rear carriage about its associated roller rotation axis WH. Similarly, the roller unit 18 is rotatable about its associated roller rotation axis Wv on the front carriage 16, which extends along a longitudinal axis Lv. The respective longitudinal axis LH and Lv can each be considered as an axis or direction of extension orthogonal to the roller rotation axis WH and Wv, respectively, of the rear carriage 14 and the front carriage 16. Furthermore, the longitudinal axis LH of the rear carriage can also be considered the longitudinal axis LB of the soil cultivation machine 10.

[0029] In Fig. 2 A steering actuator 34 acting between the rear carriage 14 and the front carriage 16 can be seen. In the illustrated embodiment, the steering actuator 34 is designed as a piston / cylinder unit whose longitudinal extension can be changed by the supply or discharge of pressurized fluid, thereby triggering a pivoting movement of the front carriage 16 relative to the rear carriage 14 in the area of ​​the articulation joint 20. For stability reasons, for example, two steering actuators 34 can be provided, one on each side of the articulation joint 20 and acting between the rear carriage 14 and the front carriage 16.

[0030] At least one such steering actuator 34 can be assigned a steering sensor 36, which detects the position state of the steering actuator 34. This position state of the steering actuator 34 essentially represents the steering state or steering range with which the tillage machine 10 is steered in a curve driving condition. In particular, such a steering range can be described as the one in Fig. 2 The angle α between the longitudinal axis LB of the tillage machine or the rear longitudinal axis LH and the front longitudinal axis Lv is considered. In a straight-ahead steering state, which corresponds to a steering state with minimal steering range, the angle α is zero. This can be seen in Fig. 2 The angle α is also represented between the roller rotation axes WH, Wv, which are not oriented parallel to each other in a curve steering state, i.e., a steering state with a steering range deviating from the minimum steering range. If the two roller units 14, 18 have the same diameter, the roller rotation axes Wv, WH intersect at a point of intersection S. If the roller units 14, 18 have different diameters, the roller rotation axes Wv, WH projected onto the ground 22 intersect at this point of intersection S.

[0031] The travel speed of the soil cultivation machine 10 can be detected, for example, by a speed sensor 38, which detects the rotational speed of one of the roller units 14, 18, in the illustrated example, roller unit 18. Since there is essentially no slippage with respect to the soil 22 to be cultivated during the operation of such a soil cultivation machine 10, it can be assumed that the rotational speed of, for example, the roller unit 18 is uniquely linked to the travel speed of the soil cultivation machine 10. Alternatively, the travel speed could also be derived from the position of the hydraulically actuated travel drive system or the position of the travel control device 30.

[0032] According to the present invention, the soil compactor 10 is operated in such a way that there is a fundamental relationship between the maximum permissible driving speed of the soil cultivation machine 10 and the steering state, i.e., for example, the extent to which the front carriage 16 is articulated relative to the rear carriage 14 in the area of ​​the articulation joint 20, which in turn is represented by the angle α. Fig. 3 shows a relationship between the steering extent L, for example represented by the steering angle α, and the driving speed V of the tillage machine 10. In particular, the Fig. 3 Based on curve K, a steering angle-travel speed relationship is established, which specifies the maximum permissible travel speed at which the tillage machine 10 can be operated depending on the current steering state or steering angle. This actual steering angle, detected, for example, by the steering sensor 36 and represented by the angle α, is considered the actual steering angle.

[0033] The Fig. 3 This shows that the soil cultivation machine 10 can, in principle, be operated at a speed between a minimum V min and a maximum V max. The minimum speed V min could, for example, correspond to a speed of 0 km / h, i.e., a standstill. The maximum speed V max could, for example, be the maximum possible speed and be around 20 km / h. It could also be provided that the maximum speed V max can be limited by an operator to a value below the maximum possible speed.

[0034] The steering range L can be adjusted between a minimum steering range L min, i.e. a steering angle α of 0° or a straight-ahead steering state, and a maximum steering range L max, which can be in the range of approximately 35° when considering the angle α as the steering angle or steering range.

[0035] The steering angle-travel speed relationship represented by curve K can be divided into two ranges, K1 and K2. Range K1 corresponds to a range of comparatively low travel speeds for the tillage machine 10, in which it operates at a speed below a threshold travel speed Vs of, for example, approximately 5 km / h. In this speed range, there is no critical relationship between the steering angle and the travel speed, so that for any travel speed within this range, the maximum steering angle Lmax can be selected, or a restriction of the maximum permissible travel speed based on the steering angle L does not apply.

[0036] If the driving speed V exceeds the threshold driving speed Vs, the maximum permissible driving speed decreases with increasing steering angle L, according to the range of the steering angle-driving speed relationship K represented by range K2. When the steering angle L is within the range of a threshold steering angle Ls, the maximum permissible driving speed corresponds to the maximum possible driving speed Vmax of the tillage machine 10. As the steering angle increases towards the maximum steering angle Lmax, the maximum permissible driving speed decreases until it reaches the threshold driving speed Vs, which is then specified as the maximum permissible driving speed when the steering angle reaches the maximum steering angle Lmax.

[0037] If the soil cultivation machine 10 is steered only to a comparatively small extent, which means that in the example shown the steering dimension is less than the threshold steering dimension L s, a limitation of the travel speed is not necessary, so that if the steering dimension L is less than the threshold steering dimension L s the soil cultivation machine 10 can be moved over the soil to be cultivated at a travel speed V max if desired.

[0038] Taking into account the in Fig. 3 The soil cultivation machine 10 can be operated in such a way that, if it is moved over the ground 22 at a speed in the range between the threshold speed V s and the maximum speed V max, for example starting from a straight-ahead steering state, i.e. a steering state with minimum steering dimension L min, no intervention in the driving speed takes place as long as the steering dimension is below the threshold steering dimension L s and / or the driving speed V specified according to the actuation of the driving control device 30 does not exceed the maximum permissible driving speed associated with the respective current steering dimension.

[0039] If the steering state is changed towards a steering state with a greater steering angle, this can lead to the current driving speed exceeding the maximum permissible driving speed associated with the steering state with the greater steering angle. This causes the drive system to be controlled by the control unit 32 in such a way that the driving speed is reduced until it corresponds to the maximum permissible driving speed associated with the currently existing steering state. This is achieved, for example, by intervening in the hydraulic drive system by reducing the delivery volume of one or more hydraulic pumps and / or reducing the displacement volume of one or more hydraulic motors.If the steering actuation device 28 is actuated in such a state in the direction of further steering, i.e. further increasing the steering range L, this results in a further reduction of the driving speed V to the maximum permissible driving speed associated with the then existing actual steering state.

[0040] Starting from a state where the vehicle speed has been reduced due to a comparatively large steering angle, if the steering angle is reduced again, the vehicle speed can also be increased accordingly, possibly down to the speed that was set by an operator before the reduction in speed was initiated. This means that as the steering angle decreases, the vehicle speed is automatically increased in line with the increasing maximum permissible speed, for example, until the vehicle speed set before the reduction was initiated is reached again.As long as the maximum permissible speed, which depends on the current steering position, is still below the speed set before the intervention, the speed can only be increased to the maximum permissible speed corresponding to the current steering input. Only when this is below the previously set speed can the previously set speed be restored.

[0041] As an alternative to this automatic return of the travel speed to the value present before the control intervention, it is possible to allow or enable an increase in travel speed only if this is actually confirmed by an operator of the tillage machine 10. For this purpose, an operating element, for example in the form of a switch, a push button or the like, can be provided at the control station 24, via which an operator can enter a speed increase confirmation, whereupon, under the control of the control unit 32, the travel drive system is operated in such a way that the speed is increased again, for example to the travel speed specified or present before the intervention to reduce the travel speed.To indicate to the operator that the driving speed can be increased again, it may be provided, for example, that when the steering input has been reduced to a value such that the driving speed existing before the intervention can actually be reached again, corresponding information is displayed, for example on a display, so that the operator can then release the speed increase by manipulating the control device.

[0042] If the tillage machine 10 is operated in a curve steering state, i.e. a state with a steering angle α other than zero, and the speed of the tillage machine 10 is increased in such a steering state that it would exceed the maximum permissible travel speed associated with the steering state or the actual steering dimension, since the target travel speed specified according to the actuation dimension of the drive control device 30 is higher than the maximum permissible travel speed specified for the existing actual steering state, the travel speed is only increased until the maximum permissible travel speed for this actual steering state is reached.When the steering control 28 is actuated to increase the steering angle, this also results in a reduction of the maximum permissible travel speed, which in turn necessitates an intervention in the drive system to reduce the travel speed to the then-current maximum permissible travel speed. If, starting from such a state, the steering control 28 is actuated in the direction of a smaller steering angle, the maximum permissible travel speed increases, so that the travel speed of the tillage machine 10 can then automatically be increased towards the target travel speed specified by the actuation of the drive control 30. However, as long as the maximum permissible travel speed remains below this target travel speed, the maximum permissible travel speed will not actually be exceeded.Only when the maximum permissible driving speed falls below the target driving speed by further reducing the steering angle, i.e., a smaller actual steering angle, can the speed be increased to the target driving speed and the soil cultivation machine 10 be moved according to the target driving speed specified by the extent of the actuation of the driving control device 30.

[0043] As an alternative to this automated increase of the driving speed to the target driving speed, i.e., without interaction by an operator, it can also be provided that when the steering angle is reduced, a change in the driving speed, starting from the initially reduced driving speed and below the target driving speed, namely the initially specified maximum permissible driving speed, is only increased if an operator provides a corresponding confirmation of the speed increase by manipulating a confirmation device provided for this purpose.Here, too, it could be provided, for example, that if, based on the current steering state, the soil cultivation machine 10 can actually be moved at the target travel speed, this is signaled acoustically or visually to the operator, so that he can then release the increase in travel speed by manipulating the control device.

[0044] The inventive method, in which the steering range is used as a guide parameter for the maximum permissible driving speed within a range of steering angle and driving speed, fundamentally avoids potentially critical driving situations that could result in the tillage machine tipping over or at least leading to uneven tillage performance. Nevertheless, the tillage machine remains steerable to a maximum extent, thus preventing situations in which a tillage machine can no longer be moved into a desired area or past an obstacle due to limited steering capability.

[0045] It should be noted that this approach can also be applied to differently structured tillage machines, for example, tillage machines where steering is achieved by each of the two roller units being pivotally mounted on a central machine frame via a steering bracket. Other parameters can also be used to provide information about the travel speed or steering angle. For example, the travel speed can be determined by changes in the position information provided by a satellite-based positioning system. The steering angle can also be derived from the actuation of a steering control device, which can be detected by sensors associated with such a device.

[0046] The relationship between steering angle and vehicle speed can, particularly in the range where the maximum permissible vehicle speed varies with the steering angle, exhibit a different behavior than that shown in Fig. 3 exhibit the depicted linear progression. For example, a step-like progression could be chosen, as well as a parabolic or asymptotic progression. Furthermore, it should be noted that the steering input-vehicle speed relationship is not necessarily to be represented in the form of a diagram, as shown in Fig. 3 The information that is displayed must be stored. This could also be provided in the form of one or more mathematical formulas or a characteristic map.

Claims

1. A method for operating a soil processing machine, wherein the soil processing machine comprises two roller units (14, 18) arranged at a distance from one another in a machine longitudinal direction (L), wherein each of the two roller units (14, 18) is rotatable around a roller axis of rotation (WH, Wv), wherein the two roller units (14, 18) are pivotable with respect to one another in order to steer the soil processing machine (10), wherein in a straight-ahead steering state corresponding to a steering state of the soil processing machine with a minimum extent of steering (Lmin), the roller axes of rotation (WH, WV) of the two roller units (14, 18) are oriented essentially in parallel to one another, and in a cornering steering state corresponding to a steering state of the soil processing machine (10) having an extent of steering differing from the minimum extent of steering (Lmin), the roller axes of rotation (WH, WV) of the two roller units (14, 18) have an orientation with respect to one another that deviates from a parallel orientation, wherein the method comprises the following measure: b) detecting an actual extent of steering of the soil processing machine (10), characterized in that the method further comprises the following measures: a) providing an extent of steering-driving speed relationship (K) reflecting a maximum permissible driving speed as a function of the extent of steering (L), c) setting a driving speed (V) of the soil processing machine (10) in such a way that the driving speed (V) does not exceed the maximum permissible driving speed assigned to the actual extent of steering detected in measure b) in accordance with the extent of steering-driving speed relationship (K) provided in measure a).

2. The method as claimed in claim 1, characterized in that if the driving speed is above the maximum permissible driving speed assigned to the actual extent of steering of the soil processing machine (10), the driving speed (V) is reduced in measure c) in such a way that the driving speed (V) essentially corresponds to the maximum permissible driving speed assigned to the actual extent of steering.

3. The method as claimed in claim 2, characterized in that if, after decreasing the driving speed (V) to the maximum permissible driving speed assigned to the actual extent of steering, the steering state is changed in the direction toward a steering state with a lesser extent of steering (L): - the driving speed (V) is increased to the maximum permissible driving speed assigned to the steering state having a lesser extent of steering (L) if the driving speed (V) existing before the reduction of the driving speed (V) is higher than the maximum permissible driving speed assigned to the steering state having a lesser extent of steering (L), or - the driving speed (V) is increased to the driving speed (V) existing before the reduction of the driving speed (V) if the driving speed (V) existing before the reduction of the driving speed (V) is less than the maximum permissible driving speed assigned to the steering state having a lesser extent of steering (L).

4. The method as claimed in claim 3, characterized in that the driving speed (V) is increased automatically to the maximum permissible driving speed assigned to the steering state with a smaller extent of steering (L) or to the driving speed (V) that existed before the driving speed (V) was reduced when the steering state changes in the direction toward the steering state with a smaller extent of steering (L).

5. The method as claimed in claim 3, characterized in that the driving speed (V) is increased to the maximum permissible driving speed assigned to the steering state with a smaller extent of steering (L) or to the driving speed (V) that existed before the driving speed (V) was reduced when the steering state changes in the direction toward the steering state with a smaller extent of steering (L) only when a speed increase confirmation is present.

6. The method as claimed in to any one of claims 1-5, characterized in that if the driving speed (V) of the soil processing machine is to be increased, starting from a driving speed (V) below the maximum permissible driving speed assigned to the actual extent of steering, to a target driving speed above the maximum permissible driving speed assigned to the actual extent of steering, in measure c) the driving speed (V) of the soil processing machine (10) is increased in such a way that it essentially corresponds to the maximum permissible driving speed assigned to the actual extent of steering.

7. The method as claimed in claim 6, characterized in that if, after increasing the driving speed (V) to the maximum permissible driving speed assigned to the actual extent of steering, the steering state is changed in the direction toward a steering state with a lesser extent of steering (L): - the driving speed (V) is increased in such a way that it essentially corresponds to the maximum permissible driving speed assigned to the steering state having a lesser extent of steering (L) if the target driving speed is higher than the maximum permissible driving speed assigned to the steering state having a lesser extent of steering (L), or - the driving speed (V) is increased in such a way that it essentially corresponds to the target driving speed if the target driving speed is less than the maximum permissible driving speed assigned to the steering state having a lesser extent of steering (L).

8. The method as claimed in claim 7, characterized in that the driving speed (V) is increased automatically to the maximum permissible driving speed assigned to the steering state with a smaller extent of steering (L) or to the target driving speed when the steering state changes in the direction toward the steering state with a smaller extent of steering (L).

9. The method as claimed in claim 7, characterized in that the driving speed (V) is increased to the maximum permissible driving speed assigned to the steering state with a smaller extent of steering (L) or to the target driving speed when the steering state changes in the direction toward the steering state with a smaller extent of steering (L) only when a speed increase confirmation is present.

10. The method as claimed in any one of claims 1-9, characterized in that at least in one range of the driving speed (V), the maximum permissible driving speed decreases essentially linearly with increasing extent of steering (L).

11. The method as claimed in any one of claims 1-10, characterized in that when the extent of steering (L) is below a threshold extent of steering (LS), the maximum permissible driving speed corresponds to a maximum driving speed (Vmax).

12. The method as claimed in any one of claims 1-11, characterized in that when the driving speed (V) is below a threshold driving speed (Vs), there is no change in the driving speed dependent on an extent of steering (L).

13. The method as claimed in any one of claims 1-12, characterized in that the extent of steering (L) is determined based on a positioning state of at least one steering actuator (34), and / or in that the extent of steering (L) is determined based on an extent of actuation of a steering actuating element (28).

14. The method as claimed in any one of claims 1-13, characterized in that the driving speed (V) is determined based on a rotational speed of at least one of the roller units (14, 18) and / or in that the driving speed (V) is determined based on a positioning state of a hydraulic drive system for at least one of the roller units, and / or in that the driving speed (V) is determined based on an positioning state of a driving actuating element (30), and / or in that the driving speed (V) is determined based on position information provided by a position detection system.