Method and system for controlling the acceleration of a vehicle cabin in the Z-direction

Abstract

Methods for controlling acceleration (a z ) of a cabin (2) of a vehicle (1) in a Z-direction, wherein the acceleration (a z ) in the Z-direction from an output torque (T output ) a drive source (4) of the vehicle (1); wherein the drive source (4) is provided with an output shaft (22) which is connected to at least one drive wheel of the vehicle (1), wherein the method comprises the steps to: a) Regulating the output torque (T output ) the driving source (4) in response to a difference (e) between a reference acceleration (a z,ref ) in the Z-direction and a measured acceleration (a z,meas ) in the Z-direction to reduce the acceleration (a z ) the cabin (2) in the Z-direction; and b) Calculating an output torque derivative (dT) based on the difference (e) between the reference acceleration (a z,ref) in the Z-direction and the measured acceleration (a z,meas ) in the Z direction to establish a torque derivation limit (dT) lim ) to determine the acceleration (az) in the cabin (2) in the Z direction.

Description

Technical field

[0001] The invention relates to a method and a system for controlling the acceleration of a vehicle cabin in the Z-direction according to the accompanying claims. The invention also relates to a computer program, a computer-readable medium, and a vehicle according to the accompanying claims. Background and state of the art

[0002] Vehicle handling, the feeling of control, and driver comfort are crucial aspects in the development of modern vehicles, such as heavy vehicles like trucks or buses. Therefore, it is essential that the vehicle meets the driver's expectations and desires. In addition to material modifications, the vehicle's control software can be developed and improved to enhance its drivability.

[0003] Gear shifting is one area where software could be used to control vehicle drivability. A common way to shift gears in a vehicle transmission is to reduce the torque transmitted from the engine to the clutch to zero and then shift the transmission into neutral. The engine speed can then be controlled to synchronize the gears being engaged. Once the new gear is engaged, the torque can be increased to the level requested by the driver.

[0004] A vehicle's powertrain can be defined as a group of components that generate the power requested by the driver and transmit that power to the vehicle's drive wheels and then to the road. Due to the varying properties and torsional effects within the powertrain, vibrations can occur when the force and torque within the powertrain change.

[0005] The engine and transmission can be controlled during gear changes to manage the drivetrain's behavior. This drivetrain behavior can affect the vehicle's drivability, the feeling of control, and driver comfort.

[0006] German patent application DE 10 2013 218 021 A1 discloses methods and devices for damping vibrations in a vehicle. The device comprises a first sensor that generates a first signal indicating a first phase angle of a first wheel of the vehicle, and a second sensor that generates a second signal indicating a second phase angle of a second wheel of the vehicle. The device further comprises a control module that, based on the first and second signals, outputs a third signal to adjust at least the first phase angle and / or the second phase angle when the vehicle detects a vibration.

[0007] The publication US 2013 / 0297109A1 (and the patent family member DE 102013104658A1) discloses a vehicle comprising an electrically driven traction motor and a control system for steering the vehicle. The traction motor can be selectively coupled to the vehicle's drive wheels by means of a clutch located between them. In one embodiment, by changing the torque or the clutch pressure, drivetrain vibrations perceived by a vehicle occupant can be dampened based on a difference between the rotational speed of a drivetrain component and a filtered rotational speed of the drivetrain component.

[0008] German patent application DE 10 2015 008 656 A1 discloses a method and a system for limiting vibrations in a vehicle cabin. The system measures cabin vibrations when one or more of at least two different configurations of injector corrections (corresponding to adjustments of the amount of fuel injected into the engine by the injectors) are used in the vehicle, the measurements using at least one accelerometer located in the vehicle. The measurement results are then used to limit vibrations.

[0009] German patent application DE 10 2012 221 837 A1 discloses a method and a device for controlling the acceleration of a vehicle body, taking into account protruding areas / road surface irregularities determined by an acceleration sensor. The measured acceleration data are filtered by a bandpass filter, which is selected to match the vibrations occurring in the drivetrain. Based on the filtered acceleration data, a target torque of the drivetrain is applied with a corresponding compensating torque. Brief description of the invention

[0010] Vibrations that can occur when force and torque in the powertrain change can be transmitted to the vehicle cabin, thus affecting vehicle handling, the feeling of control, and driver comfort. Even if vibrations in the powertrain components are reduced, the vehicle cabin may still vibrate when torque changes during gear shifting due to variations in the vehicle's propulsive force. The vibrations generated in the vehicle, and therefore in the cabin, can have different directions. The perpendicular direction, relative to the vehicle's direction of travel, can be defined as the Z-direction. The vehicle's direction of travel itself can be defined as the X-direction.When the gears are shifted and the torque is changed, the altered driving force of the vehicle results in a change in torque at the drive wheels and drive shafts. This change in torque at the drive wheels and drive shafts causes vibrations in the Z-direction of the vehicle's cabin. These Z-direction vibrations can be uncomfortable for the driver and passengers in the cabin.

[0011] There is a need to further develop a method and a system that reduce cabin discomfort caused by movements resulting from changes in the propulsive force from the powertrain. There is also a need to further develop a method and a system where the gearshift in a vehicle reduces cabin movements from the perspective of comfort and drivability. Finally, there is a need to further develop a method and a system where the gearshift in a vehicle reduces cabin movements from the perspective of wear on the components used in the cabin's suspension system.

[0012] Therefore, the object of the invention is to develop a method and a system that reduce cabin discomfort caused by movements resulting from changes in the propulsive force from the drivetrain. Another object of the invention is to develop a method and a system in which the gearshift in a vehicle reduces cabin movements from the perspective of comfort and drivability. A further object of the invention is to develop a method and a system in which the gearshift in a vehicle reduces cabin movements from the perspective of wear on components used in the cabin's suspension system.

[0013] According to the invention, a method, a computer program, a computer-readable medium, a system, and a vehicle are provided as defined in the independent claims. Developments are described in the dependent claims.

[0014] The tasks mentioned here can be accomplished by the aforementioned methods and systems for controlling the acceleration of a vehicle cabin in the Z-direction according to the attached claims.

[0015] According to the invention, a method for controlling the acceleration of a vehicle cabin in a Z-direction is provided, wherein the acceleration in the Z-direction originates from an output torque of a drive source of the vehicle. The drive source is provided with an output shaft that is connected to at least one drive wheel of the vehicle. The method comprises the steps of: a) Regulating the output torque of the drive source in response to a difference between a reference acceleration in the Z-direction and a measured acceleration in the Z-direction to reduce the acceleration of the cabin in the Z-direction; and b) Calculating an output torque derivative based on the difference between the reference acceleration in the Z direction and the measured acceleration

[0016] Acceleration in the Z direction to establish a torque derivation limit to reduce acceleration in the cabin in the Z direction.

[0017] This method can control gear shifting with regard to cabin comfort rather than the internal states of the powertrain. Comfort is improved by minimizing accelerations in the Z-direction during gear shifting. The movements are controlled by the power source. Using this method to reduce vibrations may eliminate the need for additional actuators with appropriate control systems. The durability of dampers and springs can be improved by controlling and / or suppressing cabin movements. The output torque of the power source can be controlled so that acceleration in the Z-direction follows a reference acceleration set to a value considered comfortable. The power source can be an internal combustion engine and / or an electric motor.

[0018] A torque output limit can be used to apply output torque to deliver a desired acceleration in the Z-direction of the cabin. The acceleration in the Z-direction of the front part of a vehicle chassis and the acceleration in the Z-direction of the cabin are closely related. The dynamics in the Z-direction between the front part of the chassis and the cabin can be compensated. An algorithm can be used in a control arrangement to manage the output torque output for optimal comfort. The torque's descent and ascent ramps before and after gear changes can be configured differently.

[0019] The procedure preferably also includes the step to: c) before step a): Setting the reference acceleration in the Z direction to a value that is considered acceptable for an acceleration of the cabin in the Z direction.

[0020] The reference acceleration in the Z-direction can be set to a value considered acceptable and comfortable based on experience gained from comfort studies. The comfort experience can include a subjective element. Eliminating all vibrations in a vehicle can provide the best possible comfort. However, various studies suggest that vibrations in the Z-direction in the range of 4 to 8 Hz and vibrations in the X-direction in the range of 1 to 2 Hz can be highly unpleasant for the human body. Therefore, reducing vibrations in the Z-direction in the range of 4 Hz and above can be particularly beneficial.

[0021] The procedure preferably also includes the step to: d) Increase the torque derivation limit and the output torque if the difference between the reference acceleration in the Z direction and the measured acceleration in the Z direction is negative.

[0022] Before gear changes, the torque can be reduced to zero. This reduced torque can represent a graphical descent slope. The reference acceleration in the Z-direction is set to a value considered comfortable based on experience gained from comfort studies. The difference between the reference acceleration in the Z-direction and the measured acceleration in the Z-direction can be calculated by iterating a control arrangement. If the difference is negative, this means that a larger output torque can be applied to the drive wheels, and the saturation limits, defined by the torque derivative limit, can be increased. The tuning parameters of a control arrangement for a descent slope situation can include the reference acceleration in the Z-direction and a constant value that is added to the saturation limits in case the difference can be negative.

[0023] The procedure preferably also includes the step to: d) Keeping the torque derivation limit constant if the difference between the reference acceleration in the Z direction and the measured acceleration in the Z direction is positive.

[0024] If the difference between the reference acceleration in the Z-direction and the measured acceleration in the Z-direction is positive, this means that the acceleration in the Z-direction has reached the reference acceleration. The saturation, represented by the torque derivative limit, can then be maintained at the same level until the difference between the reference acceleration in the Z-direction and the measured acceleration signal in the Z-direction becomes negative again. The tuning parameters of the descending-edge control arrangement are the reference acceleration in the Z-direction and a constant value that is added to the saturation limits in case the difference can be positive.

[0025] The procedure preferably also includes the step to: d) Reducing the torque derivation limit if the difference between the reference acceleration in the Z direction and the measured acceleration in the Z direction is positive.

[0026] If the difference between the reference acceleration in the Z-direction and the measured acceleration in the Z-direction is positive, this means that the acceleration in the Z-direction has reached the reference acceleration. Then, the saturation, represented by the torque derivative limit, can be reduced so that the difference between the reference acceleration in the Z-direction and the measured acceleration in the Z-direction can be zero or negative. The tuning parameters of the descent-slope control arrangement are the reference acceleration in the Z-direction and a constant value that is added to the saturation limits in case the difference is positive.

[0027] The procedure preferably also includes the step to: d) Increase the torque derivation limit and the output torque if the difference between the reference acceleration in the Z direction and the measured acceleration in the Z direction is positive.

[0028] After shifting gears, the driver may demand torque. This increased torque can be represented by a graphical ramp. The reference acceleration in the Z-direction is set to a value considered comfortable based on experience gained from comfort studies. The difference between the reference acceleration in the Z-direction and the measured acceleration in the Z-direction can be calculated by iterating a control arrangement. If the difference is positive, this means that a greater output torque can be applied to the drive wheels, and the saturation limits, defined by the torque derivative limit, can be increased. The tuning parameters of a control arrangement for a ramp-up situation can include the reference acceleration in the Z-direction and a constant value that is added to the saturation limits in case the difference is positive.

[0029] The procedure preferably also includes the step to: d) Keeping the torque derivation limit and the output torque constant if the difference between the reference acceleration in the Z direction and the measured acceleration in the Z direction can be negative.

[0030] If the difference between the reference acceleration in the Z-direction and the measured acceleration in the Z-direction is negative, the saturation, represented by the torque derivative limit, is maintained at the same level until the difference between the reference acceleration in the Z-direction and the measured acceleration signal in the Z-direction can again be positive. The tuning parameters of a control arrangement for a rising-edge situation can be the reference acceleration in the Z-direction and a constant value that is added to the saturation limits in case the difference can be negative.

[0031] The procedure preferably also includes the step to: d) Reducing the torque derivation limit and the output torque if the difference between the reference acceleration in the Z direction and the measured acceleration in the Z direction is negative.

[0032] If the difference between the reference acceleration in the Z-direction and the measured acceleration in the Z-direction is negative, the saturation, represented by the torque derivation limit, can be reduced until the difference between the reference acceleration in the Z-direction and the measured acceleration signal in the Z-direction can again be positive. The tuning parameters of a control arrangement for a rising-edge situation can be the reference acceleration in the Z-direction and a constant value that is added to the saturation limits in case the difference can be negative.

[0033] According to the invention, a system for controlling the acceleration of a vehicle cabin in a Z-direction is provided, comprising a control arrangement, wherein the control arrangement comprises: Means of regulating the output torque of the drive source in response to a difference between a reference acceleration in the Z direction and a measured acceleration in the Z direction, in order to reduce the acceleration of the cabin in the Z direction. Means of calculating an output torque derivative based on the difference between the reference acceleration in the Z-direction and the measured acceleration in the Z-direction, in order to define a torque derivative limit to reduce the acceleration in the cabin in the Z-direction.

[0034] The system can include a control arrangement that manages gear shifting with regard to cabin comfort rather than the internal states of the powertrain. Comfort is improved by minimizing accelerations in the Z-direction during gear shifting. Movements are controlled by the power source. Using this system to reduce vibrations may eliminate the need for additional actuators or control systems. The durability of dampers and springs can be improved by controlling and / or suppressing cabin movements. The output torque of the power source can be controlled so that acceleration in the Z-direction follows a reference acceleration set at a value considered comfortable. The power source can be an internal combustion engine and / or an electric motor.

[0035] A torque output limit can be used to apply output torque to deliver a desired acceleration in the Z-direction of the cabin. The acceleration in the Z-direction of the front part of a vehicle chassis and the acceleration in the Z-direction of the cabin are closely related. The dynamics in the Z-direction between the front part of the chassis and the cabin can be compensated. An algorithm can be used in a control arrangement to manage the output torque output for optimal comfort. The torque's descent and ascent ramps before and after gear changes can be configured differently.

[0036] The tax arrangement preferably also includes: Means of adjusting the reference acceleration in the Z-direction to a value considered acceptable for cabin acceleration in the Z-direction.

[0037] The reference acceleration in the Z-direction can be set to a value considered acceptable and comfortable based on experience gained from comfort studies. The comfort experience can include a subjective element. Eliminating all vibrations in a vehicle can provide the best possible comfort. However, various studies suggest that vibrations in the Z-direction in the range of 4 to 8 Hz and vibrations in the X-direction in the range of 1 to 2 Hz can be highly unpleasant for the human body. Therefore, reducing vibrations in the Z-direction in the range of 4 Hz and above can be particularly beneficial.

[0038] Additional objectives, advantages, and novel features of the invention will become apparent to the person skilled in the art from the following details and through the implementation of the invention. Although the invention is described below, it should be clear that the invention is not limited to the specifically described details. The person skilled in the art, having access to the present teachings, will recognize additional applications, modifications, and inclusions in other areas that are within the scope of the invention. Brief description of the drawings

[0039] The following is a description of exemplary preferred embodiments with reference to the accompanying drawings. These show: Fig. 1 schematically a vehicle in a side view which is equipped with a system for controlling the acceleration of a cabin of the vehicle in the Z direction according to an embodiment, Fig. 2 schematically a drive train in a top view, which is equipped with a system for controlling the acceleration of a cabin of the vehicle in the Z direction according to an embodiment, Fig. 3. A graph showing the variation of output torque over time during gear shifting. Fig. 4 a block diagram of a control arrangement according to an embodiment, and Fig. 5 a flowchart for a method for controlling the acceleration of a vehicle cabin in the Z direction according to one embodiment. Detailed description

[0040] Fig. Figure 1 schematically shows a vehicle 1 in a side view, which may be equipped with a system 7 for controlling the acceleration of a cabin 2 of the vehicle 1 in the Z-direction according to one embodiment. The vehicle 1 may also be equipped with a drive train 3 comprising a power source 4, a clutch 5, a transmission 6, a driveshaft 10, and drive wheels 8. The power source 4 may be an internal combustion engine and / or an electric motor, which may be coupled to the transmission 6 via the clutch 5. The transmission 6 may be connected to the drive wheels 8 of the vehicle 1 via the driveshaft 10. The vehicle 1 may also include front wheels 9. The transmission 6 may include gears 12 that can be shifted in different gear ratios. The vehicle 1 may be a heavy vehicle 1, e.g., a truck or a bus. Alternatively, the vehicle 1 may be a passenger car.Vehicle 1 can be manually operated, remotely controlled, or autonomously operated. Vehicle 1 can be rear-wheel drive, meaning that the power from drive source 4 is transmitted to the rear wheels of vehicle 1. Thus, the rear wheels can be the drive wheels 8 of vehicle 1.

[0041] The cabin 2 and the wheels 8, 9 can be suspended from a chassis 16 of the vehicle 1 by means of springs and dampers 14. The suspension of the cabin 2 can reduce vibrations that can occur when driving on a road and when the force and torque in the drive train 3 change.

[0042] Sensors 18, 19 can be arranged on the chassis 16, the cabin 2, and the wheels 8, 9 for data acquisition. The sensors 18, 19 can be accelerometers 18 and position sensors 19. The position sensors 19 on the wheels 8, 9 measure the distance between the central axis 21, 23 of the wheels 8, 9 and the chassis 16. The position sensors 19 between the chassis 16 and the cabin 2 measure the distance between the cabin 2 and the chassis 16. The accelerometers 18 and the position sensors 19 measure the acceleration and the position in the Z-direction. The perpendicular direction with respect to the direction of travel of the vehicle 1 can be defined as the Z-direction. The direction of travel of the vehicle 1 can be defined as the X-direction. When the vehicle 1 is positioned on a road, the X-direction coincides with the longitudinal direction of the vehicle 1. The Z-direction is orthogonal to the X-direction and perpendicular to the road.

[0043] The vibrations that can occur in the cabin when driving on a road, and when the force and torque from the drive source 4 change, can arise from the torque generated at the central axis 21 of the rear wheels 8. The chassis 16 can act similarly to a lever arm, and the torque generated at the central axis 21 is transmitted to the cabin via the chassis 16. A change in the torque from the drive source 4, and thus in the torque generated at the central axis 21, can cause accelerations and vibrations in the Z-direction of the cabin.

[0044] Fig. Figure 2 schematically shows a top view of a drive train 3, which is equipped with a system 7 for controlling the acceleration of a cabin 2 of the vehicle 1 in the Z-direction according to one embodiment. The drive source 4, which can be an internal combustion engine and / or an electric motor, can be equipped with a flywheel 20 arranged on an output shaft 22 of the drive source 4. The force and torque from the drive source 4 can be transmitted to the drive wheels 8 via the clutch 5, the transmission 6, the driveshaft 10, a differential 24, and drive shafts 26.

[0045] A control unit 28 can be arranged to control the acceleration of a cabin 2 of the vehicle 1 in the Z-direction. The control unit 28 can be connected to the drive source 4, the clutch 5, the transmission 6, and the accelerometers 18 and position sensors 19. The control unit 28 can include a computer 29 or a connection to a computer 29, which includes a computer program P with program code for receiving data containing the driving conditions of the vehicle 1 in order to calculate and control the acceleration of a cabin 2 of the vehicle 1 in the Z-direction. The program code can be executed in the computer 29. The control unit 28 can also store data in a memory M or have a connection to readable data containing parameters for a reference acceleration a. z,ref ( Fig. 4) in the Z-direction, which is responsible for the acceleration a z ( Fig. 4) the cabin 2 in the Z-direction is considered acceptable, and includes various vehicle operating modes to control the acceleration of a cabin 2 of the vehicle 1 in the Z-direction. A computer program product may comprise a computer-readable medium and the computer program P, wherein the computer program P may be contained in the computer-readable medium.

[0046] Fig. Figure 3 shows a graph of the variation in output torque over time during gear shifting. When the gears are shifted in transmission 6, the output torque T output ( Fig. 4), which is transmitted from the drive source 4 to the clutch 5, is reduced to zero, and then the gearbox 6 is shifted into neutral. The reduced output torque T out-put can a graphical descent slope 30 in Fig. 3. The speed from the drive source 4 can then be controlled to synchronize the gears 12 to be engaged. When the new gear is engaged, the output torque T can be output The torque from drive source 4 can be increased upon request by the driver of vehicle 1. The increased torque can be represented by a graphical rise slope 32 in Fig. 3.

[0047] Fig. Figure 4 shows a block diagram of a control arrangement 34 according to one embodiment. The control arrangement 34 includes means for regulating the output torque T. output the drive source 4 in response to a difference e between a reference acceleration a z,ref in the Z-direction and a measured acceleration a z,meas in the Z-direction, to increase the acceleration a zto reduce the Z-direction of cabin 2. The control arrangement 34 of system 7 can control the gear shifting with reference to cabin 2 comfort rather than the internal states of the drivetrain 3. Comfort is improved by minimizing accelerations in the Z-direction during gear shifting. The movements are controlled by the drive source 4. It may be that using system 7 to reduce vibrations does not require additional actuators with suitable control systems. The durability of dampers and springs 14 can be improved by controlling and / or suppressing the cabin 2 movements. The output torque of the drive source 4 is controlled such that the Z-direction acceleration is less than a reference acceleration a. z,ref This is followed by a value set to what is considered comfortable. The measured acceleration a z,measAlternatively, the acceleration of cabin 2 in the Z-direction can be a predicted acceleration that can be based on various measured variables.

[0048] The control arrangement 34 can also provide means for adjusting the reference acceleration a z,ref in the Z-direction to a value that is sufficient for the acceleration a z Cabin 2 is considered comfortable in the Z-direction. The reference acceleration a z,refThe vibration level in the Z-direction can be set to a value considered comfortable based on experience gained from comfort studies. However, the experience of comfort can include a subjective element, and eliminating all vibrations in a vehicle may represent the best possible comfort. Nevertheless, various studies suggest that vibrations in the Z-direction in the range of 4 to 8 Hz and vibrations in the X-direction in the range of 1 to 2 Hz can be highly unpleasant for the human body. Therefore, reducing vibrations in the Z-direction in the range of 4 Hz and above can be particularly beneficial.

[0049] The control arrangement 34 can further include means, such as a first controller 36, to derive an output torque dT based on the difference e between the reference acceleration a z,ref in the Z-direction and the measured acceleration a z,measto calculate in the Z-direction in order to determine a torque derivation limit dT lim to achieve the torque derivation limit dT. lim can be used to generate an output torque T output to exert a desired acceleration in the Z-direction of the cabin 2. The acceleration in the Z-direction of the front part of the chassis 16 and the acceleration in the Z-direction of the cabin 2 are closely related. The dynamics in the Z-direction between the front part of the chassis 16 and the cabin 2 can be compensated. An algorithm can be used in the control arrangement 34 to control the output torque for optimal comfort. The downward slope 30 and the upward slope 32 of the torque before and after gear changes can be designed differently.

[0050] A reference torque can be a torque demanded by the driver. The demanded torque T reqThis should be achieved without causing excessive acceleration in cabin 2 in the Z-direction. The reference torque, and thus the required torque T, req The reference torque (T) should be zero at the end of the downhill slope (30) before shifting gears. At the end of the uphill slope (32), the reference torque, and thus the required torque T, can be determined. req , which may be identical to the torque at the beginning of the descent slope 30, but may alternatively be different from this torque due to changed conditions during gear shifting.

[0051] Based on the torque derivation limit dT lim can the output torque T output The output torque T is calculated and controlled in a second and third controller 38, 40. output is applied with the required torque T req compared, and if the output torque T output the required torque T reqOnce this has been achieved, the control order 34 is deactivated.

[0052] The control arrangement 34 controls the rising flank 32 and the descending flank 30 so that vibrations of the drivetrain 3 can be suppressed. Therefore, the rising flank 32 and the descending flank 30 are modified in the control arrangement 34 to improve comfort. The shape of the descending flank 30 and the rising flank 32 can be changed when gears are shifted to improve comfort for the driver and passengers in the cabin 2 of the vehicle 1. The timing of the gear shift can be critical in some situations. On an incline, it can be important to execute the gear shift within a short period to maintain the speed and movement of the vehicle 1 before and after the gear shift. Therefore, the period in which the rising flank 32 and the descending flank 30 are executed can be limited.

[0053] The saturation limits in the control arrangement 34 can be used to apply a motor torque that produces a desired acceleration in the Z-direction in the cabin 2. The acceleration in the Z-direction in the cabin 2 can be used as feedback. The dynamics in the Z-direction between the chassis 16 and the cabin 2 can be compensated in the control arrangement 34. A stabilization time can be constant or dynamic. The reference torque can be the torque T requested by the driver of the vehicle 1. req The descent slope 30 and the ascent slope 32 can be designed differently.

[0054] The algorithm for the relegation flank 30 can be defined as: 1: while Offramp active do 2: Set a z,ref 3: Calculate the error, e 4: if e ≤ 0 then 5: Set saturation limits = saturation limits + constant 6: else 7: Set saturation limits = saturation limits 8: end if 9: end while

[0055] The algorithm for rising edge 32 can be defined as: 1: while Offramp active do 2: Set a z,ref 3: Calculate the error, e 4: if e ≥ 0 then 5: Set saturation limits = saturation limits + constant 6: else 7: Set saturation limits = saturation limits 8: end if 9: end while

[0056] Acceleration in the Z-direction can be sensitive to large, sudden changes in motor torque. Therefore, acceleration in the Z-direction can be used as feedback in the control arrangement 34 to determine the difference e between the measured acceleration a. z,meas and the reference acceleration a z,ref to calculate. The control arrangement 34 can be part of the control unit 28.

[0057] Fig.Figure 5 shows a flowchart for a method for controlling the acceleration of a cabin 2 of the vehicle 1 in the Z-direction according to one embodiment. The vehicle 1 can include the features described in the embodiments above.

[0058] The process may include the step to: a) Regulating the output torque T output the drive source 4 in response to a difference e between a reference acceleration a z,ref in the Z-direction and a measured acceleration a z,meas in the Z-direction to reduce the acceleration a z cabin 2 in the Z-direction.

[0059] The method can control gear shifting with reference to cabin 2 comfort rather than the internal states of the drivetrain 3. Comfort is improved by minimizing accelerations in the Z-direction during gear shifting. The movements are controlled by the drive source 4. It may be that using the method to reduce vibrations eliminates the need for additional actuators with appropriate control systems. The durability of dampers and springs 14 can be improved by controlling and / or suppressing cabin 2 movements. The output torque of the drive source 4 can be controlled so that the acceleration in the Z-direction is close to a reference acceleration a. z,ref This is followed by a value set to what is considered comfortable. The measured acceleration a z,measAlternatively, the acceleration of cabin 2 in the Z-direction can be a predicted acceleration based on various measured variables.

[0060] The process may include a further step towards: b) before step a): Setting the reference acceleration a z,ref in the Z-direction to a value that is used for the acceleration a z Cabin 2 is considered comfortable in the Z-direction.

[0061] The reference acceleration a z,refThe vibration in the Z-direction can be adjusted to a value that, based on experience from comfort studies, is considered acceptable and comfortable. The comfort experience can include a subjective element. Eliminating all vibrations in a vehicle can provide the best possible comfort. However, various studies suggest that vibrations in the Z-direction in the range of 4 to 8 Hz and vibrations in the X-direction in the range of 1 to 2 Hz can be highly unpleasant for the human body. Therefore, reducing vibrations in the Z-direction in the range of 4 Hz and above can be particularly beneficial.

[0062] The process may include a further step towards: c) Calculating an output torque derivative dT based on the difference e between the reference acceleration a z,ref in the Z-direction and the measured acceleration a z,measin the Z-direction, to establish a torque derivation limit dT lim to reach.

[0063] A torque derivation limit dT lim It can be used to exert an output torque to deliver a desired acceleration in the Z-direction of the cabin 2. The acceleration in the Z-direction of the front part of a chassis 16 and the acceleration in the Z-direction of the cabin 2 are closely related. The dynamics in the Z-direction between the front part of the chassis 16 and the cabin 2 can be compensated. An algorithm can be used in a control arrangement 34 to control the output torque output for optimal comfort. The descent slope 30 and the ascent slope 32 of the torque before and after gear changes can be designed differently.

[0064] The process may include the further step of: d) Increasing the torque derivation limit dT limand the output torque T output , if the difference e between the reference acceleration a z,ref in the Z-direction and the measured acceleration a z,meas is negative in the Z-direction.

[0065] Before the gears are shifted, the torque can be reduced to zero. The reduced torque can be represented by a graphical descent slope 30. The reference acceleration a z,ref In the Z-direction, a value is set that is considered comfortable based on experience from comfort studies.

[0066] The difference e between the reference acceleration a z,ref in the Z-direction and the measured acceleration a z,measThe difference in the Z-direction can be calculated by iterating the control arrangement 34. If the difference is negative, this means that a larger output torque is exerted on the drive wheels 8 and the saturation limits, defined by the torque derivation limit, can be increased. The tuning parameters of the control arrangement 34 for a situation with a descent slope 30 can determine the reference acceleration a. z,ref in the Z-direction and a constant value that is added to the saturation limits in case the difference can be negative. The constant value can be a value adapted for system 7 and can be positive or negative, depending on whether the output torque T output to be increased or decreased.

[0067] The process may include the further step of: d) Keeping the torque derivation limit dT constant lim, if the difference e between the reference acceleration a z,ref in the Z-direction and the measured acceleration a z,meas is positive in the Z-direction.

[0068] If the difference e between the reference acceleration a z,ref in the Z-direction and the measured acceleration a z,meas If the value in the Z-direction is positive, this means that the acceleration in the Z-direction is greater than the reference acceleration a. z,ref has been reached. Then the saturation, which is determined by the torque derivation limit dT, can be reached. lim is represented, kept at the same level until the difference e between the reference acceleration a z,ref in the Z direction and the measured acceleration signal a z,meas in the Z-direction it is negative again. The tuning parameters of the control arrangement with descent slope 30 are the reference acceleration a z,refin the Z-direction and a constant value that is added to the saturation limits in case the difference can be positive. The constant value can be a value adapted for system 7 and can be positive or negative, depending on whether the output torque T output to be increased or decreased.

[0069] The process may include the further step of: d) Reducing the torque derivation limit dT lim , if the difference e between the reference acceleration a z,ref in the Z-direction and the measured acceleration a z,meas is positive in the Z-direction.

[0070] If the difference e between the reference acceleration a z,ref in the Z-direction and the measured acceleration a z,meas If the value in the Z-direction is positive, this means that the acceleration in the Z-direction is greater than the reference acceleration a. z,refhas been reached. Then the saturation, which is determined by the torque derivation limit dT, can be reached. lim The difference e between the reference acceleration a is shown to be reduced, so that the difference e between the reference acceleration a z,ref in the Z-direction and the measured acceleration a z,meas in the Z-direction can be zero or negative. The tuning parameters of the control arrangement 34 with descent slope are the reference acceleration a z,ref in the Z-direction and a constant value that is added to the saturation limits in case the difference can be positive. The constant value can be a value adapted for system 7 and can be positive or negative, depending on whether the output torque T output to be increased or decreased.

[0071] The process may include a further step towards: d) Increasing the torque derivation limit dT lim and the output torque T output, if the difference e between the reference acceleration a z,ref in the Z-direction and the measured acceleration a z,meas is positive in the Z-direction.

[0072] After shifting gears, the driver can demand torque. The increased torque can be represented by a graphical ramp 32. The reference acceleration a z,ref In the Z-direction, a value is set that is considered comfortable based on experience from comfort studies. The difference e between the reference acceleration a z,ref in the Z-direction and the measured acceleration a z,measThe difference in the Z-direction can be calculated by iterating the control arrangement 34. If the difference is positive, this means that a larger output torque can be applied to the drive wheels 8 and the saturation limits, defined by the torque derivation limit, can be increased. The tuning parameters of a control arrangement 34 for a situation with a rising slope 32 can determine the reference acceleration a. z,ref in the Z-direction and a constant value that is added to the saturation limits in case the difference can be positive. The constant value can be a value adapted for system 7 and can be positive or negative, depending on whether the output torque T output to be increased or decreased.

[0073] The process may include the further step of: d) Keeping the torque derivation limit dT constant lim and the output torque T output, if the difference e between the reference acceleration a z,ref in the Z-direction and the measured acceleration a z,meas can be negative in the Z-direction.

[0074] If the difference between the reference acceleration a z,ref in the Z-direction and the measured acceleration a z,meas If the value in the Z-direction is negative, the saturation, which is determined by the torque derivation limit dT, will be... lim is displayed, kept at the same level until the difference e between the reference acceleration a z,ref in the Z-direction and the measured acceleration a z,meas in the Z-direction it can again be positive. The tuning parameters of the control arrangement 34 for a situation with rising edge 32 can determine the reference acceleration a z,refin the Z-direction and a constant value that is added to the saturation limits, in case the difference can be negative. The constant value can be a value adapted for system 7 and can be positive or negative, depending on whether the output torque T output to be increased or decreased.

[0075] According to another aspect of the invention, the method includes the further step to: d) Reducing the torque derivation limit dT lim and the output torque T output , if the difference between the reference acceleration a z,ref in the Z-direction and the measured acceleration a z,meas is negative in the Z-direction. If the difference between the reference acceleration a z,ref in the Z-direction and the measured acceleration a z,meas If the value in the Z-direction is negative, the saturation, which is determined by the torque derivation limit dT, can occur. limis shown, reduced until there is a difference between the reference acceleration a z,ref in the Z direction and the measured acceleration signal a z,meas in the Z-direction it can again be positive. The tuning parameters of a control arrangement 34 for a situation with a rising edge 32 can determine the reference acceleration a z,ref in the Z-direction and a constant value that is added to the saturation limits in case the difference can be negative. The constant value can be a value adapted for system 7 and can be positive or negative, depending on whether the output torque T output to be increased or decreased.

[0076] The computer program comprises program code which, when executed on computer 29, causes computer 29 to perform the aforementioned procedure. The computer program product comprises the computer-readable medium and the computer program, the computer program being contained in the computer-readable medium.

Claims

[1] Methods for controlling acceleration (a z ) of a cabin (2) of a vehicle (1) in a Z-direction, wherein the acceleration (a z ) in the Z-direction from an output torque (T output ) a drive source (4) of the vehicle (1); wherein the drive source (4) is provided with an output shaft (22) which is connected to at least one drive wheel of the vehicle (1), wherein the method comprises the steps to: a) Regulating the output torque (T output ) the driving source (4) in response to a difference (e) between a reference acceleration (a z,ref ) in the Z-direction and a measured acceleration (a z,meas ) in the Z-direction to reduce the acceleration (a z ) the cabin (2) in the Z-direction; and b) Calculating an output torque derivative (dT) based on the difference (e) between the reference acceleration (a z,ref) in the Z-direction and the measured acceleration (a z,meas ) in the Z direction to establish a torque derivation limit (dT) lim ) to determine the acceleration (az) in the cabin (2) in the Z direction. [2] The method of claim 1, comprising the further step to: c) before step a): Setting the reference acceleration (a z,ref ) in the Z-direction to a value that is suitable for the acceleration (a z ) the cabin (2) in the Z-direction is considered acceptable. [3] The method of claim 2, comprising the further step to: d) Increasing the torque derivation limit (dT) lim ) and the output torque (T output ), if the difference (e) between the reference acceleration (a z,ref ) in the Z-direction and the measured acceleration (a z,meas ) is negative in the Z-direction. [4] The method of claim 2, comprising the further step to: d) Keeping the torque derivation limit constant (dT) lim ), if the difference (e) between the reference acceleration (a z,ref ) in the Z-direction and the measured acceleration (a z,meas ) is positive in the Z-direction. [5] The method of claim 2, comprising the further step to: d) Reducing the torque derivation limit (dT) lim ) if the difference (e) between the reference acceleration (a z,ref ) in the Z-direction and the measured acceleration (a z,meas ) is positive in the Z-direction. [6] The method of claim 2, comprising the further step to: d) Increasing the torque derivation limit (dT) lim ) and the output torque (T output ), if the difference (e) between the reference acceleration (a z,ref ) in the Z-direction and the measured acceleration (a z,meas ) is positive in the Z-direction. [7] The method of claim 2, comprising the further step to: d) Keeping the torque derivation limit constant (dT) lim ) and the output torque (T output ), if the difference (e) between the reference acceleration (a z,ref ) in the Z-direction and the measured acceleration (a z,meas ) is negative in the Z-direction. [8] The method of claim 2, comprising the further step to: d) Reducing the torque derivation limit (dT) lim ) and the output torque (T output ), if the difference (e) between the reference acceleration (a z,ref ) in the Z-direction and the measured acceleration (a z,meas ) is negative in the Z-direction. [9] Computer program (P), wherein the computer program comprises program code to cause a control unit (28) or a computer (29) connected to the control unit (28) to perform the method according to any of the preceding claims. [10] Computer-readable medium comprising instructions which, when executed by a control unit (28) or a computer (29) connected to the control unit (28), cause the control unit (28) or the computer (29) to execute the method according to any one of claims 1 to 8. [11] System (7) for controlling an acceleration (a z ) a cabin (2) of a vehicle (1) in a Z-direction comprising a control arrangement (34), wherein the control arrangement (34) comprises: Means for regulating an output torque (T) output ) the driving source (4) in response to a difference (e) between a reference acceleration (a z,ref) in the Z-direction and a measured acceleration (a z,meas ) in the Z-direction to increase the acceleration (a z ) of the cabin (2) in the Z-direction; and Means for calculating an output torque derivative (dT) based on the difference (e) between the reference acceleration (a z,ref ) in the Z-direction and the measured acceleration (a z,meas ) in the Z-direction. to a torque derivation limit (dT) lim ) to determine the acceleration (az) in the cabin (2) in the Z direction. [12] System (7) according to claim 11, wherein the control arrangement (34) further comprises: Means for setting the reference acceleration (a z,ref ) in the Z-direction to a value that is suitable for the acceleration (a z ) the cabin (2) in the Z-direction is considered acceptable. [13] Vehicle (1) comprising a system (7) according to claim 11 or 12.

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