DE102021211863A1 - Method and device for determining whether a vehicle is traveling forwards or backwards - Google Patents

Abstract

The invention relates to a method and a device for determining whether a vehicle is driving forwards or reversing, in which a forward driving variable is determined in each case for at least two wheels of the motor vehicle using mathematical forward driving relationships describing forward driving, - using mathematical reverse driving relationships describing backward driving for a reversing variable is determined for the same wheels of the motor vehicle, - the spread of the forward drive variables and the spread of the reverse drive variables are determined and - forward travel is then determined as present if the spread of the forward drive variables is smaller than the spread of the reverse drive variables and - reversing then as it is determined in the present case if the scatter range of the reverse travel variables is smaller than the scatter range of the forward travel variables.

Description

State of the art

In the DE 42 23 385 A1 a method for detecting reversing of a motor vehicle is described. For this purpose, the yaw rate and a model yaw rate are obtained, and a factor is determined with the aid of these quantities and constants, the value of which is compared with predetermined comparative values. From the comparison, it is derived whether forward or reverse travel is taking place.

Disclosure of Invention

• - mittels eine Vorwärtsfahrt beschreibender mathematischer Vorwärtsfahrtbeziehungen für wenigstens zwei Räder des Kraftfahrzeugs jeweils eine Vorwärtsfahrtgröße ermittelt werden,
• - mittels eine Rückwärtsfahrt beschreibender mathematischer Rückwärtsfahrtbeziehungen für dieselben Räder des Kraftfahrzeugs jeweils eine Rückwärtsfahrtgröße ermittelt wird,
• - der Streubereich der Vorwärtsfahrtgrößen und der Streubereich der Rückwärtsfahrtgrößen ermittelt werden und
• - eine Vorwärtsfahrt dann als vorliegend ermittelt wird, wenn der Streubereich der Vorwärtsfahrtgrößen kleiner als der Streubereich der Rückwärtsfahrtgrößen ist und
• - eine Rückwärtsfahrt dann als vorliegend ermittelt wird, wenn der Streubereich der Rückwärtsfahrtgrößen kleiner als der Streubereich der Vorwärtsfahrtgrößen ist.

The invention relates to a method for determining whether a vehicle is traveling forwards or backwards, in which

• - a forward travel variable is determined for at least two wheels of the motor vehicle by means of mathematical forward travel relationships describing forward travel,
• - a reversing variable is determined by means of mathematical reversing relationships describing reversing for the same wheels of the motor vehicle,
• - the scatter range of the forward travel variables and the scatter range of the reverse travel variables are determined and
• - A forward drive is then determined as being present if the scatter range of the forward drive variables is smaller than the scatter range of the reverse drive variables and
• - Reversing is then determined as being present when the scatter range of the reverse travel variables is smaller than the scatter range of the forward travel variables.

It is thus possible in a simple manner to recognize the direction of travel or the presence of forward or reverse travel.

An advantageous embodiment of the invention is characterized in that the scatter range is the difference between the smallest determined value and the largest determined value. The scatter range of the reversing variables is thus the difference between the smallest and the largest determined reversing variable. The scatter range of the forward travel variable is thus the difference between the smallest and the largest determined forward travel variable.

An advantageous embodiment of the invention is characterized in that the forward driving parameters and the reverse driving parameters are determined for all wheels of the vehicle.

An advantageous embodiment of the invention is characterized in that the vehicle is a four-wheel motor vehicle. In this case, four forward driving parameters and four reverse driving parameters are determined.

An advantageous embodiment of the invention is characterized in that the forward travel variables and the reverse travel variables are the individual wheel speeds transformed to the geometric center of gravity of the vehicle.

$$\begin{array}{l}\text{v}\_\text{FR}\_\text{CoG}=(\left(\text{v}\_\text{FR}\_\text{wheel}-\text{vy}\_\text{CoG}+\left(\text{Yr}*\text{lx}\_\text{FA}\right)*\text{sinLw}\_\text{FR}\right)\text{/}\text{cosLw}\_\text{FR})\\ -\left(\text{Yr}*\text{l}\raisebox{1ex}{$1$}\!\left/ \!\raisebox{-1ex}{$2$}\right.\text{y\_FA}\right)\end{array}$$

$$\begin{array}{l}\text{v}\_\text{RL}\_\text{CoG}=(\left(\text{v}\_\text{RL}\_\text{wheel}-\text{vy}\_\text{CoG}-\left(\text{Yr}*\text{lx}\_\text{RA}\right)*\text{sinLw}\_\text{RL}\right)\text{/}\text{cosLw}\_\text{RL})\\ +\left(\text{Yr}*\text{l}\raisebox{1ex}{$1$}\!\left/ \!\raisebox{-1ex}{$2$}\right.\text{y\_RA}\right)\end{array}$$

$$\begin{array}{l}\text{v}\_\text{RR}\_\text{CoG}=(\left(\text{v}\_\text{RR}\_\text{wheel}-\text{vy}\_\text{CoG}-\left(\text{Yr}*\text{lx}\_\text{RA}\right)*\text{sinLw}\_\text{RR}\right)\text{/}\text{cosLw}\_\text{RR})\\ -\left(\text{Yr}*\text{l}\raisebox{1ex}{$1$}\!\left/ \!\raisebox{-1ex}{$2$}\right.\text{y\_RA}\right)\end{array}$$

und die Rückwärtsfahrtgrößen gemäß der Beziehungen $$\begin{array}{l}\text{v}\_\text{FL}\_\text{CoG}=(\left(\text{v}\_\text{FL}\_\text{wheel}+\text{vy}\_\text{CoG}+\left(\text{Yr}*\text{lx}\_\text{FA}\right)*\text{sinLw}\_\text{FL}\right)\text{/}\text{cosLw}\_\text{FL})\\ -\left(\text{Yr}*\text{l}\raisebox{1ex}{$1$}\!\left/ \!\raisebox{-1ex}{$2$}\right.\text{y\_FA}\right)\end{array}$$

$$\begin{array}{l}\text{v}\_\text{FR}\_\text{CoG}=(\left(\text{v}\_\text{FR}\_\text{wheel}+\text{vy}\_\text{CoG}+\left(\text{Yr}*\text{lx}\_\text{FA}\right)*\text{sinLw}\_\text{FR}\right)\text{/}\text{cosLw}\_\text{FR})\\ +\left(\text{Yr}*\text{l}\raisebox{1ex}{$1$}\!\left/ \!\raisebox{-1ex}{$2$}\right.\text{y\_FA}\right)\end{array}$$

$$\begin{array}{l}\text{v}\_\text{RL}\_\text{CoG}=(\left(\text{v}\_\text{RL}\_\text{wheel}+\text{vy}\_\text{CoG}-\left(\text{Yr}*\text{lx}\_\text{RA}\right)*\text{sinLw}\_\text{RL}\right)\text{/}\text{cosLw}\_\text{RL})\\ -\left(\text{Yr}*\text{l}\raisebox{1ex}{$1$}\!\left/ \!\raisebox{-1ex}{$2$}\right.\text{y\_RA}\right)\end{array}$$

$$\begin{array}{l}\text{v}\_\text{RR}\_\text{CoG}=(\left(\text{v}\_\text{RR}\_\text{wheel}+\text{vy}\_\text{CoG}-\left(\text{Yr}*\text{lx}\_\text{RA}\right)*\text{sinLw}\_\text{RR}\right)\text{/}\text{cosLw}\_\text{RR})\\ +\left(\text{Yr}*\text{l}\raisebox{1ex}{$1$}\!\left/ \!\raisebox{-1ex}{$2$}\right.\text{y\_RA}\right)\end{array}$$

ermittelt werden, wobei die Variablennamen die fogende Bedeutung haben:

• v_xy_CoG: auf den Schwerpunkt transformierte Radgeschwindigkeit des Rades xy, wobei xy dabei einen der vier Werte FL, FR, RL und RR annimmt und wobei FL das linke Vorderrad, FR das rechte Vorderrad, RL das linke Hinterrad und RR das rechte Hinterrad kennzeichnet.
• v_xy_wheel: mit Raddrehzahlsensor ermittelte Radgeschwindigkeit des Rades xy,
• vy_CoG: Fahrzeuggeschwindigkeit in Querrichtung,
• Yr: Gierrate,
• sinLw_xy und cosLw_xy: Sinuswert und Cosinuswert des Radlenkwinkels am Rad xy,
• IxFA und IxRA: Abstand in Fahrzeuglängsrichtung von vorderer bzw. hinterer Achse bis zum Schwerpunkt sowie
• |½y_FA bzw. |½y_RA: halbe Spurbreite an vorderer bzw. hinterer Achse.

An advantageous embodiment of the invention is characterized in that the forward travel variables according to the relationships $$\begin{array}{l}\text{v\_FL\_CoG}=(\left(\text{v\_FL\_wheel}-\text{vy\_CoG}+\left(\text{yr}*\text{lx\_FA}\right)*\text{sinLw\_FL}\right)\text{/}\text{cosLw\_FL})\\ +\left(\text{yr}*\text{I}\raisebox{1ex}{$1$}\!\left/ \!\raisebox{-1ex}{$2$}\right.\text{y\_FA}\right)\end{array}$$

$$\begin{array}{l}\text{v}\_\text{FR}\_\text{CoG}=(\left(\text{v}\_\text{FR}\_\text{wheel}-\text{vy}\_\text{CoG}+\left(\text{yr}*\text{lx}\_\text{FA}\right)*\text{sinLw}\_\text{FR}\right)\text{/}\text{cosLw}\_\text{FR})\\ -\left(\text{yr}*\text{l}\raisebox{1ex}{$1$}\!\left/ \!\raisebox{-1ex}{$2$}\right.\text{y\_FA}\right)\end{array}$$

$$\begin{array}{l}\text{v}\_\text{RL}\_\text{CoG}=(\left(\text{v}\_\text{RL}\_\text{wheel}-\text{vy}\_\text{CoG}-\left(\text{yr}*\text{lx}\_\text{RA}\right)*\text{sinLw}\_\text{RL}\right)\text{/}\text{cosLw}\_\text{RL})\\ +\left(\text{yr}*\text{l}\raisebox{1ex}{$1$}\!\left/ \!\raisebox{-1ex}{$2$}\right.\text{y\_RA}\right)\end{array}$$

$$\begin{array}{l}\text{v}\_\text{RR}\_\text{CoG}=(\left(\text{v}\_\text{RR}\_\text{wheel}-\text{vy}\_\text{CoG}-\left(\text{yr}*\text{lx}\_\text{RA}\right)*\text{sinLw}\_\text{RR}\right)\text{/}\text{cosLw}\_\text{RR})\\ -\left(\text{yr}*\text{l}\raisebox{1ex}{$1$}\!\left/ \!\raisebox{-1ex}{$2$}\right.\text{y\_RA}\right)\end{array}$$

and the reversing quantities according to the relationships $$\begin{array}{l}\text{v}\_\text{FL}\_\text{CoG}=(\left(\text{v}\_\text{FL}\_\text{wheel}+\text{vy}\_\text{CoG}+\left(\text{yr}*\text{lx}\_\text{FA}\right)*\text{sinLw}\_\text{FL}\right)\text{/}\text{cosLw}\_\text{FL})\\ -\left(\text{yr}*\text{l}\raisebox{1ex}{$1$}\!\left/ \!\raisebox{-1ex}{$2$}\right.\text{y\_FA}\right)\end{array}$$

$$\begin{array}{l}\text{v}\_\text{FR}\_\text{CoG}=(\left(\text{v}\_\text{FR}\_\text{wheel}+\text{vy}\_\text{CoG}+\left(\text{yr}*\text{lx}\_\text{FA}\right)*\text{sinLw}\_\text{FR}\right)\text{/}\text{cosLw}\_\text{FR})\\ +\left(\text{yr}*\text{l}\raisebox{1ex}{$1$}\!\left/ \!\raisebox{-1ex}{$2$}\right.\text{y\_FA}\right)\end{array}$$

$$\begin{array}{l}\text{v}\_\text{RL}\_\text{CoG}=(\left(\text{v}\_\text{RL}\_\text{wheel}+\text{vy}\_\text{CoG}-\left(\text{yr}*\text{lx}\_\text{RA}\right)*\text{sinLw}\_\text{RL}\right)\text{/}\text{cosLw}\_\text{RL})\\ -\left(\text{yr}*\text{l}\raisebox{1ex}{$1$}\!\left/ \!\raisebox{-1ex}{$2$}\right.\text{y\_RA}\right)\end{array}$$

$$\begin{array}{l}\text{v}\_\text{RR}\_\text{CoG}=(\left(\text{v}\_\text{RR}\_\text{wheel}+\text{vy}\_\text{CoG}-\left(\text{yr}*\text{lx}\_\text{RA}\right)*\text{sinLw}\_\text{RR}\right)\text{/}\text{cosLw}\_\text{RR})\\ +\left(\text{yr}*\text{l}\raisebox{1ex}{$1$}\!\left/ \!\raisebox{-1ex}{$2$}\right.\text{y\_RA}\right)\end{array}$$

be determined, whereby the variable names have the following meaning:

• v_xy_CoG: wheel speed of wheel xy transformed to the center of gravity, where xy assumes one of the four values FL, FR, RL and RR and where FL denotes the left front wheel, FR the right front wheel, RL the left rear wheel and RR the right rear wheel.
• v_xy_wheel: wheel speed of wheel xy determined with wheel speed sensor,
• vy_CoG: vehicle speed in lateral direction,
• Yr: yaw rate,
• sinLw_xy and cosLw_xy: sine value and cosine value of the wheel steering angle at wheel xy,
• IxFA and IxRA: Distance in the longitudinal direction of the vehicle from the front or rear axle to the center of gravity and
• |½y_FA or |½y_RA: half the track width on the front or rear axle.

The invention also includes a device containing means that are designed to carry out the method according to the invention. This is in particular a control device in which the program code of the method according to the invention is stored.

The drawing includes 1 .

In 1 the sequence of an embodiment of the method according to the invention is shown in a basic manner.

When transforming the four measured wheel speeds of a four-wheeled vehicle to the vehicle's geometric center of gravity, the mathematical transformation formulas valid for forward travel differ from the formulas valid for reverse travel.

The basic idea of the invention is based on the fact that both the first transformation formulas, which are valid for forward travel, and the second transformation formulas, which are valid for reverse travel, are applied to the wheel speeds.

This gives two sets for four transformed wheel speeds each.

$$\begin{array}{l}\text{v}\_\text{FR}\_\text{CoG}=(\left(\text{v}\_\text{FR}\_\text{wheel}-\text{vy}\_\text{CoG}+\left(\text{Yr}*\text{lx}\_\text{FA}\right)*\text{sinLw}\_\text{FR}\right)\text{/}\text{cosLw}\_\text{FR})\\ -\left(\text{Yr}*\text{l}\raisebox{1ex}{$1$}\!\left/ \!\raisebox{-1ex}{$2$}\right.\text{y\_FA}\right)\end{array}$$

$$\begin{array}{l}\text{v}\_\text{RL}\_\text{CoG}=(\left(\text{v}\_\text{RL}\_\text{wheel}-\text{vy}\_\text{CoG}-\left(\text{Yr}*\text{lx}\_\text{RA}\right)*\text{sinLw}\_\text{RL}\right)\text{/}\text{cosLw}\_\text{RL})\\ +\left(\text{Yr}*\text{l}\raisebox{1ex}{$1$}\!\left/ \!\raisebox{-1ex}{$2$}\right.\text{y\_RA}\right)\end{array}$$

$$\begin{array}{l}\text{v}\_\text{RR}\_\text{CoG}=(\left(\text{v}\_\text{RR}\_\text{wheel}-\text{vy}\_\text{CoG}-\left(\text{Yr}*\text{lx}\_\text{RA}\right)*\text{sinLw}\_\text{RR}\right)\text{/}\text{cosLw}\_\text{RR})-\\ \left(\text{Yr}*\text{l}\raisebox{1ex}{$1$}\!\left/ \!\raisebox{-1ex}{$2$}\right.\text{y\_RA}\right)\end{array}$$

The transformation formulas valid for forward travel are: $$\begin{array}{l}\text{v}\_\text{FL}\_\text{CoG}=(\left(\text{v}\_\text{FL}\_\text{wheel}-\text{vy}\_\text{CoG}+\left(\text{yr}*\text{lx}\_\text{FA}\right)*\text{sinLw}\_\text{FL}\right)\text{/}\text{cosLw}\_\text{FL})\\ +\left(\text{yr}*\text{l}\raisebox{1ex}{$1$}\!\left/ \!\raisebox{-1ex}{$2$}\right.\text{y\_FA}\right)\end{array}$$

$$\begin{array}{l}\text{v}\_\text{FR}\_\text{CoG}=(\left(\text{v}\_\text{FR}\_\text{wheel}-\text{vy}\_\text{CoG}+\left(\text{yr}*\text{lx}\_\text{FA}\right)*\text{sinLw}\_\text{FR}\right)\text{/}\text{cosLw}\_\text{FR})\\ -\left(\text{yr}*\text{l}\raisebox{1ex}{$1$}\!\left/ \!\raisebox{-1ex}{$2$}\right.\text{y\_FA}\right)\end{array}$$

$$\begin{array}{l}\text{v}\_\text{RL}\_\text{CoG}=(\left(\text{v}\_\text{RL}\_\text{wheel}-\text{vy}\_\text{CoG}-\left(\text{yr}*\text{lx}\_\text{RA}\right)*\text{sinLw}\_\text{RL}\right)\text{/}\text{cosLw}\_\text{RL})\\ +\left(\text{yr}*\text{l}\raisebox{1ex}{$1$}\!\left/ \!\raisebox{-1ex}{$2$}\right.\text{y\_RA}\right)\end{array}$$

$$\begin{array}{l}\text{v}\_\text{RR}\_\text{CoG}=(\left(\text{v}\_\text{RR}\_\text{wheel}-\text{vy}\_\text{CoG}-\left(\text{yr}*\text{lx}\_\text{RA}\right)*\text{sinLw}\_\text{RR}\right)\text{/}\text{cosLw}\_\text{RR})-\\ \left(\text{yr}*\text{l}\raisebox{1ex}{$1$}\!\left/ \!\raisebox{-1ex}{$2$}\right.\text{y\_RA}\right)\end{array}$$

• v_xy_CoG: auf den Schwerpunkt transformierte Radgeschwindigkeit des Rades xy. xy nimmt dabei die einen der vier Werte FL, FR, RL und RR and, wobei FL das linke Vorderrad, FR das rechte Vorderrad, RL das linke Hinterrad und RR das rechte Hinterrad kennzeichnet.
• v_xy_wheel: mit Raddrehzahlsensor ermittelte Radgeschwindigkeit des Rades xy
• vy_CoG: Fahrzeuggeschwindigkeit in Querrichtung
• Yr: Gierrate
• sinLw_xy und cosLw_xy: Sinuswert und Cosinuswert des Radlenkwinkels am Rad xy
• IxFA und IxRA: Abstand in Fahrzeuglängsrichtung von vorderer bzw. hinterer Achse bis zum Schwerpunkt
• |½y_FA bzw. |½y_RA: halbe Spurbreite an vorderer bzw. hinterer Achse

The variable names used have the following meaning:

• v_xy_CoG: wheel speed of wheel xy transformed to the center of gravity. In this case, xy assumes one of the four values FL, FR, RL and RR, with FL identifying the left front wheel, FR the right front wheel, RL the left rear wheel and RR the right rear wheel.
• v_xy_wheel: wheel speed of wheel xy determined with wheel speed sensor
• vy_CoG: vehicle speed in lateral direction
• Yr: yaw rate
• sinLw_xy and cosLw_xy: Sine value and cosine value of the wheel steering angle at wheel xy
• IxFA and IxRA: Distance in the longitudinal direction of the vehicle from the front or rear axle to the center of gravity
• |½y_FA or |½y_RA: half the track width on the front or rear axle

$$\begin{array}{l}\text{v}\_\text{FR}\_\text{CoG}=(\left(\text{v}\_\text{FR}\_\text{wheel}+\text{vy}\_\text{CoG}+\left(\text{Yr}*\text{lx}\_\text{FA}\right)*\text{sinLw}\_\text{FR}\right)\text{/}\text{cosLw}\_\text{FR})+\\ \left(\text{Yr}*\text{l}\raisebox{1ex}{$1$}\!\left/ \!\raisebox{-1ex}{$2$}\right.\text{y\_FA}\right)\end{array}$$

$$\begin{array}{l}\text{v}\_\text{RL}\_\text{CoG}=(\left(\text{v}\_\text{RL}\_\text{wheel}+\text{vy}\_\text{CoG}-\left(\text{Yr}*\text{lx}\_\text{RA}\right)*\text{sinLw}\_\text{RL}\right)\text{/}\text{cosLw}\_\text{RL})-\\ \left(\text{Yr}*\text{l}\raisebox{1ex}{$1$}\!\left/ \!\raisebox{-1ex}{$2$}\right.\text{y\_RA}\right)\end{array}$$

$$\begin{array}{l}\text{v}\_\text{RR}\_\text{CoG}=(\left(\text{v}\_\text{RR}\_\text{wheel}+\text{vy}\_\text{CoG}-\left(\text{Yr}*\text{lx}\_\text{RA}\right)*\text{sinLw}\_\text{RR}\right)\text{/}\text{cosLw}\_\text{RR})+\\ \left(\text{Yr}*\text{l}\raisebox{1ex}{$1$}\!\left/ \!\raisebox{-1ex}{$2$}\right.\text{y\_RA}\right)\end{array}$$

The transformation rules valid for reversing are as follows: $$\begin{array}{l}\text{v}\_\text{FL}\_\text{CoG}=(\left(\text{v}\_\text{FL}\_\text{wheel}+\text{vy}\_\text{CoG}+\left(\text{yr}*\text{lx}\_\text{FA}\right)*\text{sinLw}\_\text{FL}\right)\text{/}\text{cosLw}\_\text{FL})-(\text{yr}\\ -*\text{l}\raisebox{1ex}{$1$}\!\left/ \!\raisebox{-1ex}{$2$}\right.\text{y}\text{\_FA})\end{array}$$

$$\begin{array}{l}\text{v}\_\text{FR}\_\text{CoG}=(\left(\text{v}\_\text{FR}\_\text{wheel}+\text{vy}\_\text{CoG}+\left(\text{yr}*\text{lx}\_\text{FA}\right)*\text{sinLw}\_\text{FR}\right)\text{/}\text{cosLw}\_\text{FR})+\\ \left(\text{yr}*\text{l}\raisebox{1ex}{$1$}\!\left/ \!\raisebox{-1ex}{$2$}\right.\text{y\_FA}\right)\end{array}$$

$$\begin{array}{l}\text{v}\_\text{RL}\_\text{CoG}=(\left(\text{v}\_\text{RL}\_\text{wheel}+\text{vy}\_\text{CoG}-\left(\text{yr}*\text{lx}\_\text{RA}\right)*\text{sinLw}\_\text{RL}\right)\text{/}\text{cosLw}\_\text{RL})-\\ \left(\text{yr}*\text{l}\raisebox{1ex}{$1$}\!\left/ \!\raisebox{-1ex}{$2$}\right.\text{y\_RA}\right)\end{array}$$

$$\begin{array}{l}\text{v}\_\text{RR}\_\text{CoG}=(\left(\text{v}\_\text{RR}\_\text{wheel}+\text{vy}\_\text{CoG}-\left(\text{yr}*\text{lx}\_\text{RA}\right)*\text{sinLw}\_\text{RR}\right)\text{/}\text{cosLw}\_\text{RR})+\\ \left(\text{yr}*\text{l}\raisebox{1ex}{$1$}\!\left/ \!\raisebox{-1ex}{$2$}\right.\text{y\_RA}\right)\end{array}$$

The variable names correspond to the variable names listed for forward travel.

It has been found that the four determined transformed wheel speeds v_FL_CoG, v_FR_CoG, v_RL_CoG and v_RR_CoG are very close together if the correct transformation formula was used to calculate them. If the other transformation formula is used, there is a greater spread of the values.

This can be used to easily determine the direction of travel of the vehicle. For this purpose, after measuring the four wheel speeds v_FL_wheel, v_FR_wheel, v_RL_wheel and v_RR_wheel, the yaw rate Yr and the determination of the transverse speed vy_CoG determines the transformed wheel speeds for both directions of travel. A bandwidth variable that characterizes the bandwidth or spread of the four transformed wheel speeds is then determined for each direction of travel.

If the bandwidth ascertained using the relationships valid for forward travel is less than the bandwidth ascertained using the relationships valid for reverse travel, then the vehicle is traveling forwards. In the opposite case, there is reverse travel.

In 1 the sequence of an embodiment of the method according to the invention is shown in a basic manner.

After the start of the method in block 100, a forward travel variable is determined in block 101 by means of mathematical forward travel relationships describing forward travel for at least two wheels of the motor vehicle. Then, in block 102, a reversing variable is determined in each case for the same wheels of the motor vehicle by means of mathematical reversing relationships describing reversing. In block 103, the scatter range of the forward travel variables and the scatter range of the reverse travel variables are then determined. In block 104, the scatter ranges are then compared. If the scatter range of the forward travel variables is smaller than the scatter range of the reverse travel variables, the presence of forward travel is determined in block 105 .

However, if after the comparison in block 104 the scatter range of the reverse travel variables is smaller than the scatter range of the forward travel variables, then block 106 is accessed and the presence of reverse travel is determined there.

QUOTES INCLUDED IN DESCRIPTION

This list of documents cited by the applicant was generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Patent Literature Cited

• DE 4223385 A1 [0001]

Claims (7)

A method for determining whether a vehicle is moving forwards or backwards, in which - by means of mathematical forward travel relationships describing forward travel for at least two wheels of the motor vehicle, a forward travel variable is determined (101), - a reversing variable is determined (102) for the same wheels of the motor vehicle by means of mathematical reversing relations describing reversing, - the scatter range of the forward travel variables and the scatter range of the reverse travel variables are determined (104) and - A forward drive is determined as present if the scatter range of the forward drive variables is smaller than the scatter range of the reverse drive variables (105) and - Reversing is determined as present if the scatter range of the reverse travel variables is smaller than the scatter range of the forward travel variables (106). procedure after claim 1 , characterized in that the scatter range is the difference between the smallest determined value and the largest determined value. procedure after claim 1 , characterized in that the forward drive variables and the reverse drive variables are determined for all wheels of the vehicle. procedure after claim 1 , characterized in that the vehicle is a four-wheel motor vehicle. procedure after claim 1 , characterized in that the forward drive variables and the reverse drive variables are wheel speeds transformed to the geometric center of gravity of the vehicle. procedure after claim 4 , characterized in that the forward travel sizes according to the relationships $$\begin{array}{l}\text{v}\_\text{FL}\_\text{CoG}=(\left(\text{v}\_\text{FL}\_\text{wheel}-\text{vy}\_\text{CoG}+\left(\text{yr}*\text{lx}\_\text{FA}\right)*\text{sinLw}\_\text{FL}\right)\text{/}\text{cosLw}\_\text{FL})\\ +\left(\text{yr}*\text{l}\raisebox{1ex}{$1$}\!\left/ \!\raisebox{-1ex}{$2$}\right.\text{y\_FA}\right)\end{array}$$

$$\begin{array}{l}\text{v}\_\text{FR}\_\text{CoG}=(\left(\text{v}\_\text{FR}\_\text{wheel}-\text{vy}\_\text{CoG}+\left(\text{yr}*\text{lx}\_\text{FA}\right)*\text{sinLw}\_\text{FR}\right)\text{/}\text{cosLw}\_\text{FR})\\ -\left(\text{yr}*\text{l}\raisebox{1ex}{$1$}\!\left/ \!\raisebox{-1ex}{$2$}\right.\text{y\_FA}\right)\end{array}$$

$$\begin{array}{l}\text{v}\_\text{RL}\_\text{CoG}=(\left(\text{v}\_\text{RL}\_\text{wheel}-\text{vy}\_\text{CoG}-\left(\text{yr}*\text{lx}\_\text{RA}\right)*\text{sinLw}\_\text{RL}\right)\text{/}\text{cosLw}\_\text{RL})\\ +\left(\text{yr}*\text{l}\raisebox{1ex}{$1$}\!\left/ \!\raisebox{-1ex}{$2$}\right.\text{y\_RA}\right)\end{array}$$

$$\begin{array}{l}\text{v}\_\text{RR}\_\text{CoG}=(\left(\text{v}\_\text{RR}\_\text{wheel}-\text{vy}\_\text{CoG}-\left(\text{yr}*\text{lx}\_\text{RA}\right)*\text{sinLw}\_\text{RR}\right)\text{/}\text{cosLw}\_\text{RR})\\ -\left(\text{yr}*\text{l}\raisebox{1ex}{$1$}\!\left/ \!\raisebox{-1ex}{$2$}\right.\text{y\_RA}\right)\end{array}$$

and the reversing quantities according to the relationships $$\begin{array}{l}\text{v}\_\text{FL}\_\text{CoG}=(\left(\text{v}\_\text{FL}\_\text{wheel}+\text{vy}\_\text{CoG}+\left(\text{yr}*\text{lx}\_\text{FA}\right)*\text{sinLw}\_\text{FL}\right)\text{/}\text{cosLw}\_\text{FL})\\ -\left(\text{yr}*\text{l}\raisebox{1ex}{$1$}\!\left/ \!\raisebox{-1ex}{$2$}\right.\text{y\_FA}\right)\end{array}$$

$$\begin{array}{l}\text{v}\_\text{FR}\_\text{CoG}=(\left(\text{v}\_\text{FR}\_\text{wheel}+\text{vy}\_\text{CoG}+\left(\text{yr}*\text{lx}\_\text{FA}\right)*\text{sinLw}\_\text{FR}\right)\text{/}\text{cosLw}\_\text{FR})\\ +\left(\text{yr}*\text{l}\raisebox{1ex}{$1$}\!\left/ \!\raisebox{-1ex}{$2$}\right.\text{y\_FA}\right)\end{array}$$

$$\begin{array}{l}\text{v}\_\text{RL}\_\text{CoG}=(\left(\text{v}\_\text{RL}\_\text{wheel}+\text{vy}\_\text{CoG}-\left(\text{yr}*\text{lx}\_\text{RA}\right)*\text{sinLw}\_\text{RL}\right)\text{/}\text{cosLw}\_\text{RL})\\ -\left(\text{yr}*\text{l}\raisebox{1ex}{$1$}\!\left/ \!\raisebox{-1ex}{$2$}\right.\text{y\_RA}\right)\end{array}$$

$$\begin{array}{l}\text{v}\_\text{RR}\_\text{CoG}=(\left(\text{v}\_\text{RR}\_\text{wheel}+\text{vy}\_\text{CoG}-\left(\text{yr}*\text{lx}\_\text{RA}\right)*\text{sinLw}\_\text{RR}\right)\text{/}\text{cosLw}\_\text{RR})\\ +\left(\text{yr}*\text{l}\raisebox{1ex}{$1$}\!\left/ \!\raisebox{-1ex}{$2$}\right.\text{y\_RA}\right)\end{array}$$

are determined, with the variable names having the meaning v_xy_CoG: wheel speed of wheel xy transformed to the center of gravity, where xy assumes one of the four values FL, FR, RL and RR and where FL is the left front wheel, FR is the right front wheel, RL is the left rear wheel and RR denotes the right rear wheel. v_xy_wheel: wheel speed of wheel xy determined with the wheel speed sensor, vy_CoG: vehicle speed in the transverse direction, Yr: yaw rate, sinLw_xy and cosLw_xy: sine value and cosine value of the wheel steering angle at wheel xy, IxFA and IxRA: distance in the vehicle longitudinal direction from the front or rear axle to the center of gravity as well |½y_FA or |½y_RA: have half the track width on the front or rear axle. Device containing means designed to carry out the method according to the invention.

Images