DE102006036818A1 - Method and device for determining an orientation of a motor vehicle - Google Patents

Abstract

For determining an orientation of a motor vehicle, which is represented by a pitch angle (TETA) and a roll angle (PHI), a pitch rate (OMEGA_TETA), a roll rate (OMEGA_PHI) and a yaw rate (OMEGA_GIER) of the motor vehicle (2) are detected. Depending on the detected pitch rate (OMEGA_TETA) and the detected yaw rate (OMEGA_GIER), the pitch angle (TETA) of the motor vehicle (2) is determined. Depending on the detected pitch rate (OMEGA_TETA), the detected roll rate (OMEGA_PHI), the detected yaw rate (OMEGA_GIER) and the determined pitch angle (TETA), the roll angle (PHI) of the motor vehicle (2) is determined. Depending on the determined pitch angle (TETA) and dependent on the determined roll angle (PHI), the orientation of the motor vehicle (2) is determined.

Description

The The invention relates to a method and a device for determining an orientation of a motor vehicle.

modern Motor vehicles regularly have control systems in, in given situations in a control of the motor vehicle intervention. The control system may be, for example, a vehicle dynamics control system and / or a driving dynamics comfort system. For example, prevents an electronic stability system a spin of the motor vehicle in the border area. The electronic stability system may comprise an anti-lock system, by blocking the wheels the braking effect is periodically canceled and reinstated. Further, the electronic stability system may include traction control comprising controlling an internal combustion engine of the motor vehicle acts by the torque transmitted to the wheels is temporarily limited so that the wheels do not spin. For such Interventions in the control of the motor vehicle is to avoid an unnecessary one or a wrong intervention the knowledge of the precise orientation of the motor vehicle very advantageous.

It The object of the invention is a method and a device for Determining an orientation of a motor vehicle to create or in each driving situation, a precise determination of the orientation of the motor vehicle allows.

The The object of the invention is achieved by the characteristics of the independent Claims. Advantageous embodiments of the invention are specified in the subclaims.

The Invention is characterized according to a first Aspect of the invention by a method and an apparatus for Determining an orientation of a motor vehicle. The orientation of the motor vehicle is characterized by a pitch angle and a roll angle represents the motor vehicle. There will be a pitch rate, a roll rate and a yaw rate of the motor vehicle detected. Dependent from the detected pitch rate and the detected yaw rate becomes a pitch angle of the motor vehicle determined. Depending on the recorded pitch rate, the recorded roll rate, the detected yaw rate and the determined Nick angle is determined a roll angle of the motor vehicle.

To capture in this context means that preferably the roll rate is detected with a roll rate of rotation sensor and / or the pitch rate is detected with a pitch yaw rate sensor and / or that preferably the yaw rate with a yaw rate of rotation sensor is detected. The acquisition of roll rate, pitch rate and yaw rate can easily lead to a very precise determination of the orientation contribute the motor vehicle. The exact knowledge of the orientation of the motor vehicle allows at least one, preferably several operating variables of the motor vehicle exactly to determine. The operating variables can be used for a vehicle dynamics control system, a driving dynamics comfort system, a navigation system and / or a Vehicle condition observer important. The farm sizes are for example, a reference speed, a slip angle, a Sollgierrate and / or a reference acceleration in any Spatial direction.

The Invention is characterized according to a second Aspect of the invention by a method and an apparatus for Determining the orientation of the motor vehicle. The orientation of the motor vehicle is by a pitch angle and by a roll angle represents the motor vehicle. It will be the pitch rate, the roll rate and the yaw rate of the motor vehicle detected. Dependent from the recorded pitch rate, the collected roll rate and the detected Yaw rate of the roll angle of the motor vehicle is determined. Depending on the detected pitch rate, the detected yaw rate and the detected Roll angle, the pitch angle of the motor vehicle is determined.

In an advantageous embodiment of the first and / or second aspect According to the invention, the roll rate is detected with a roll yaw rate sensor and / or detects the pitch rate with a pitch yaw rate sensor and / or it the yaw rate is detected with a yaw yaw rate sensor. This allows easy a precise one Detecting the roll rate of the pitch rate or the yaw rate.

In a further advantageous embodiment of the first aspect of Invention becomes dependent from the detected pitch rate and the detected yaw rate, a pitching speed of the motor vehicle determined. Depending on the pitching speed and dependent from a first damping constant the pitch angle is determined. This allows the pitch angle through numerical integration and thus contributes easily to a precise determination the orientation of the motor vehicle. Without the damping constant would be a Integral over the pitching speed is not stable. Furthermore, a system-related offset one of the yaw rate sensors to a divergent integral over the Pitching speed lead.

In a further advantageous embodiment of the second aspect of the invention, a rolling speed of the motor vehicle is determined as a function of the detected pitch rate, the detected roll rate and the detected yaw rate. Depending on the roll speed and depending on the first damping constant, the roll angle is determined. This makes it possible to determine the roll angle by numerical integration and thus contributes easily to a precise determination of the orientation of the motor vehicle. Without the damping constant, an integral over the roll rate would not be stable. Further, a systemic offset of one of the yaw rate sensors would result in a divergent integral over the roll rate.

In a further advantageous embodiment of the first aspect of Invention is checked, if current at least one start condition is met. If the start condition is satisfied, A start pitch angle and a start roll angle are determined. The start pitch angle is assigned to the pitch angle. The starting roll angle is assigned to the roll angle. This allows the pitch angle and the roll angle is determined in every driving situation of the motor vehicle can be.

In a further advantageous embodiment of the first aspect of Invention becomes a test pitch angle determined. It is checked if one Testing pitch rate is less than a first predetermined threshold and / or whether a test pitch acceleration is less than a third predetermined threshold. The test pitch angle becomes the starting pitch angle assigned if the test pitching speed is less than the first predetermined threshold and / or if the test pitch acceleration is less than the third predetermined threshold. This makes possible, the pitch angle can be determined precisely in every driving situation of the motor vehicle can.

In a further advantageous embodiment of the second aspect of Invention becomes a test roll angle determined. It will check for a check-roll speed less than a second threshold and / or a test roll acceleration is less than a fourth threshold. The test roll angle is assigned to the start roll angle if the check roll speed or the test rolling acceleration is less than the second or fourth threshold. This makes possible, that the roll angle can be determined precisely in every driving situation of the motor vehicle can.

In a further advantageous embodiment of the first and / or second Aspect of the invention, the starting pitch angle is dependent on a longitudinal acceleration of the motor vehicle and depending on a gravitational acceleration determined. Determining the starting pitch angle in a different way than determining the pitch angle allows one mutual plausibility of the determined angles.

In a further advantageous embodiment of the first and / or second Aspect of the invention, the starting roll angle is dependent on the longitudinal acceleration of the motor vehicle, a lateral acceleration of the motor vehicle and dependent determined from the gravitational acceleration. Determining the starting roll angle in a different way than determining the roll angle allows one mutual plausibility of the determined angles.

The The invention is described below with reference to schematic drawings explained in more detail.

It demonstrate:

1 a motor vehicle and a pitch angle,

2 the motor vehicle and a roll angle,

3 a program for determining the orientation of the motor vehicle,

4 a program for checking a start condition,

5 a calculation rule for determining a roll speed and a calculation rule for determining a pitch speed,

6 a calculation rule for determining the roll angle and a calculation rule for determining the pitch angle,

7 a calculation rule for determining a test roll angle and a calculation rule for determining a test pitch angle.

elements same construction or function are cross-figurative with the same Reference number marked.

A motor vehicle 2 ( 1 ) is about a transverse axis of the motor vehicle 2 turned and opposite to a plane 4 tilted with a pitch angle TETA. The car 2 can also be rotated about its longitudinal axis and opposite the plane 4 with a roll angle PHI ( 2 ) be inclined.

Preferably, the motor vehicle comprises 2 a pitch yaw rate sensor for detecting a pitch rate OMEGA_TETA and a roll yaw rate sensor for detecting a roll rate OMEGA_PHI. Furthermore, the motor vehicle includes 2 preferably a yaw rate of rotation sensor for detecting a yaw rate OMEGA_GIER. If the yaw rate OMEGA_GIER has a value not equal to zero, the motor vehicle turns 2 about an axis perpendicular to the longitudinal axis and perpendicular to the transverse axis of the motor vehicle 2 stands.

An orientation of the motor vehicle is given by the pitch angle TETA and the roll angle PHI. A very precise knowledge of the orientation of the motor vehicle 2 , in particular the pitch angle TETA and the roll angle PHI of the motor vehicle 2 may be particularly important in connection with vehicle dynamics control systems and / or vehicle dynamics comfort systems. Such control systems are for example an electronic stability system, an anti-lock braking system and / or a traction control system. Furthermore, the orientation of the motor vehicle 2 be used in a navigation system and / or a vehicle condition observer.

Especially in critical driving situations, for example, shortly before or during the spin of the motor vehicle 2 is the precise knowledge of the orientation of the motor vehicle 2 especially important, since only in a precisely determined orientation, the control systems suitable in the handling of the motor vehicle 2 can intervene. If the orientation is not at all or not sufficiently known, this can lead to a superfluous or incorrect intervention in the driving behavior of the motor vehicle 2 to lead. This can lead to an escalation of the critical driving situation.

A program ( 3 ) for determining the orientation of the motor vehicle 2 is preferably stored on a storage medium of a vehicle control system. The first program is preferably timely an engine start of the motor vehicle 2 started in a step S1. If necessary, variables are initialized in step S1.

In At a step S2, a pitch rate OMEGA_TETA, a roll rate OMEGA_PHI, and a yaw rate OMEGA_GIER detected. The pitch rate OMEGA_TETA is preferably with the pitch yaw rate sensor detected. The yaw rate OMEGA_GIER is preferably with the yaw rate of rotation sensor detected. The roll rate OMEGA_PHI is preferably used with the Wank yaw rate sensor detected.

In a step S3, depending on the yaw rate OMEGA_GIER, the pitch rate OMEGA_TETA, a damping constant C_NULL, the pitch angle TETA and the roll angle PHI, a pitching speed TETA_VEL is determined, preferably below the in 5 specified calculation rule. Furthermore, in the step S3, the roll rate PHI_VEL is determined as a function of the yaw rate OMEGA_GIER, the roll rate OMEGA_PHI, the pitch rate OMEGA_TETA, the pitch angle TETA and the roll angle PHI, preferably according to the 5 specified calculation rule. The dependence of the pitching speed TETA_VEL on the pitch angle TETA and roll angle PHI and the dependence of the roll speed PHI_VEL on the pitch angle TETA and roll angle PHI is reflected in the coupled system of differential equations 5 again. This is preferably solved iteratively according to a mathematical method known to the skilled person for solving coupled differential equations.

Preferably the program will determine the orientation of the motor vehicle in a step S4 further processed.

alternative The program can be used to determine the orientation of the motor vehicle However, also be processed in a step S11 on.

In step S11, the pitch angle TETA is determined by simply integrating the pitching speed TETA_VEL. Further, in step S11, the roll angle PHI is detected by simply integrating the roll velocity PHI_VEL. The pitching speed TETA_VEL and the roll rate PHI_VEL are determined as a function of a damping constant C_NULL ( 5 ). Without the term with the damping constant C_NULL, larger and larger roll angles PHI and pitch angle TETA would be determined during the integration in step S11. The damping term, which includes the damping constant C_NULL, causes a non-changing orientation of the motor vehicle 2 the pitch angle TETA or the roll angle PHI are reset to their initial value in a time period predetermined by the damping constant C_NULL. This allows only by the steps S1 to S3 and the step S11, the orientation of the motor vehicle 2 can be determined. The steps S1 to S3 and S11 represent a first procedure for determining the orientation of the motor vehicle 2 , The first procedure is particularly suitable for determining the orientation of the motor vehicle 2 if the orientation changes greatly within a short period of time, for example in a critical driving situation. The critical driving situation can be, for example, a rolling over of the motor vehicle. The rolling over of the motor vehicle can thus be recognized particularly well by the first procedure.

In step S4, a test pitch angle TETA_TEST is dependent on a longitudinal acceleration ACC_STR of the motor vehicle 2 determined, preferably after the in 7 specified calculation rule. The longitudinal acceleration ACC_STR is preferably detected with a first accelerometer. Furthermore, in step S4, a test roll angle PHI_TEST is dependent on a lateral acceleration ACC_DIAG and the longitudinal acceleration ACC_STR of the motor vehicle 2 be determined, preferably after the in 7 at given calculation rule. The lateral acceleration ACC_DIAG is preferably detected with a second accelerometer. In this case, the test pitch angle TETA_TEST depends on a lateral acceleration ACC_DIAG, a longitudinal acceleration ACC_STR, a longitudinal speed V_STR, a reference longitudinal acceleration V_STR_GRD, a distance L of the vehicle's rear axle to a vehicle center of gravity of the vehicle 2 and depending on a gravitational acceleration G determined. The longitudinal acceleration ACC_STR and the lateral acceleration ACC_DIAG are preferably detected with accelerometers. Preferably, intermediate results of the calculation rule according to 7 filtered with a low pass filter.

Determining the pitch angle TETA or the roll angle PHI according to the test pitch angle TETA_TEST or the test roll angle PHI_TEST ( 7 ) represents a second approach for determining the orientation of the motor vehicle 2 and makes it possible, above all, for a constant orientation of the motor vehicle over a predetermined period of time 2 the precise determination of the orientation, since the dependence on the gravitational acceleration G, a fixed reference system is given. The first approach is better for critical driving situations than the second approach. For example, during spin or during a lane change in a banked curve, the test pitch angle TETA_TEST or the test roll angle PHI_TEST may have values that do not correspond to reality.

In a step S5 is preferably for checking whether a start condition CDN has a truth value TRUE, i. whether the start condition CDN met is a testing pitch PHI_TEST_VEL dependent from the determined test pitch angle PHI_TEST determined. The test pitch speed PHI_TEST_VEL can be calculated by simply deriving the test pitch angle TETA_TEST be determined. Further, in step S5, to check if the start condition CDN has the truth value TRUE, depending on the test roll angle PHI_TEST a Test roll velocity PHI_TEST_VEL determined. The test roll speed PHI_TEST_VEL can be calculated simply by deriving the test roll angle PHI_TEST can be determined.

alternative or additionally to step S5, in step S6 for checking whether the start condition CDN has the truth value TRUE, a check pitch acceleration TETA_TEST_ACC dependent from the test pitching speed TETA_TEST_VEL can be determined. The test pitch acceleration TETA_TEST_ACC can simply by deducing the test pitch velocity TETA_TEST_VEL be determined. Alternatively or additionally, in step S6 for checking the Start condition CDN a test roll acceleration PHI_TEST_ACC can be determined. The test roll acceleration PHI_TEST_ACC can by simply temporally deriving the test roll speed PHI_TEST_VEL be determined.

In In a step S7, a program for checking the Start condition CDN started following the step S11 the program for determining the orientation of the motor vehicle is explained in more detail. If the condition of step S7 is fulfilled, then the processing is continued in a step S8. Is the condition of step S7 not fulfilled, so processing is continued in step S11.

in the Step S8 becomes the check pitch angle TETA_TEST a start pitch angle Assigned to TETA_NULL. Further, in step S8, the check roll angle PHI_TEST assigned to a start roll angle PHI_NULL.

In a step S9, the pitch angle TETA is determined as a function of the pitching speed TETA_VEL and the starting pitch angle TETA_NULL, preferably after the in 6 specified calculation rule. Furthermore, in step S9, the roll angle PHI is determined as a function of the roll speed PHI_VEL and the start roll angle PHI_NULL.

In a step S10, the program for determining the orientation of the motor vehicle 2 to be ended. Preferably, however, the program for determining the orientation of the motor vehicle 2 during operation of the motor vehicle 2 regularly processed.

The program for determining the orientation of the motor vehicle 2 in particular, the steps S1 to S9 of the program for determining the orientation of the motor vehicle 2 provide a combination of the first and second approaches for determining the orientation of the motor vehicle 2 Whenever the starting condition CDN has the truth value TRUE, that is, when the orientation of the motor vehicle 2 is relatively constant over a predetermined period of time, the first approach which is more favorable in this situation is used to determine the test pitch angle TETA_TEST or the test roll angle PHI_TEST, respectively, by setting the start pitch angle TETA_NULL to the test pitch angle TETA_TEST or the start roll angle PHI_NULL to the Test roll angle PHI_TEST is equated. At the same time, this time defines a new start time T_NULL to the Inte integrate. In the other driving situations in which the orientation of the motor vehicle 2 is not relatively unchanged, the more favorable in these situations second approach is selected, in which the pitch angle TETA and the roll angle PHI are determined depending on the detected pitch rate OMEGA_TETA, the detected roll rate OMEGA_PHI and the detected yaw rate OMEGA_GIER.

The program for checking the start condition CDN ( 4 ) is preferably started in a step S12, in which variables are initialized if necessary.

In In a step S13, it is checked whether the check pitching speed TETA_TEST_VEL is less than a pre-specified first threshold THD_1. If the condition of step S13 is satisfied, then the processing continued in a step S14. Is the condition of the step S13 not met, so the processing is continued in a step S19.

in the Step S14 is checked whether a roll rate PHI_TEST_VEL is less than a predetermined one second threshold THD_2. Is the condition of the step S14 fulfilled, so the processing is continued in a step S15. Is the Condition of step S14 is met, so the processing is continued in a step S15. Is the Condition of step S14 is not satisfied, then the processing in a step S19 continues.

alternative or additionally can still steps S15 and / or S16 are processed.

in the Step S15 is checked whether the pitch acceleration TETA_TEST_ACC is smaller than a given one third threshold THD_3. Is the condition of step S15 Fulfills, so processing is continued in step S16. Is the condition of Step S15 not fulfilled, so the processing is continued in step S19.

in the Step S16 is checked whether the test roll acceleration PHI_TEST_ACC is less than a predetermined fourth threshold THD_VIER. If the condition of step S16 is satisfied, then the processing continued in a step S17. Is the condition of the step S16 not met, so the processing is continued in step S19.

in the Step S17 is assigned the start condition CDN, the truth value TRUE.

In a step S18, the program for checking the start condition CDN may be terminated. Preferably, with the termination of the program for checking the start condition CDN, the program for determining the orientation of the motor vehicle 2 in step S7 further processed.

in the Step S19 is recognized that the start condition CDN is not Fulfills Is FALSE.

The Invention is not limited to the specified embodiments. For example, can only the pitch angle TETA or only the roll angle PHI be determined. Further, the pitch angle TETA according to the first Procedure can be determined and the roll angle PHI according to the second Proceed to be determined or the pitch angle TETA according to the second Procedure be determined and the roll angle PHI according to the first Procedure to be determined. Furthermore, the program is preferably to check the start condition CDN in the program for determining the orientation of the motor vehicle implemented.

Claims (12)

Method for determining an orientation of a motor vehicle ( 2 ), which is represented by a pitch angle (TETA) and a roll angle (PHI), in which - a pitch rate (OMEGA_TETA), a roll rate (OMEGA_PHI) and a yaw rate (OMEGA_GIER) of the motor vehicle ( 2 ) - depending on the detected pitch rate (OMEGA_TETA) and the detected yaw rate (OMEGA_GIER), the pitch angle (TETA) of the motor vehicle ( 2 ) is determined, depending on the detected pitch rate (OMEGA_TETA), the detected roll rate (OMEGA_PHI), the detected yaw rate (OMEGA_GIER) and the determined pitch angle (TETA) of the roll angle (PHI) of the motor vehicle ( 2 ) is determined. Method for determining an orientation of a motor vehicle ( 2 ) represented by a pitch angle (TETA) and a roll angle (PHI) at which - a pitch rate (OMEGA_TETA), a roll rate (OMEGA_PHI) and a yaw rate (OMEGA_GIER) of the motor vehicle are detected, - depending on the detected pitch rate ( OMEGA_TETA), the detected roll rate (OMEGA_PHI) and the detected yaw rate (OMEGA_GIER) of the roll angle (PHI) of the motor vehicle ( 2 ) is determined, depending on the detected pitch rate (OMEGA_TETA), the detected yaw rate (OMEGA_GIER) and the determined roll angle (PHI) of the pitch angle (TETA) of the motor vehicle ( 2 ) is determined. Method according to one of claims 1 or 2, in which - the pitch rate (OMEGA_TETA) is detected with a pitch yaw rate sensor and / or - the roll rate (OMEGA_PHI) is detected with a roll yaw rate sensor and / or - the yaw rate (OMEGA_GIER) is detected with a yaw yaw rate sensor. Method according to one of the preceding claims, in which - depending on the detected pitch rate (OMEGA_TETA) and the detected yaw rate (OMEGA_GIER), a pitching speed (TETA_VEL) of the motor vehicle ( 2 ) is determined, - is determined depending on the pitching speed (TETA_VEL) and depending on the first damping constant (C_NULL) of the pitch angle (TETA). Method according to one of the preceding claims, in which, depending on the detected pitch rate (OMEGA_TETA), the detected roll rate (OMEGA_PHI) and the detected yaw rate (OMEGA_GIER), a roll rate (PHI_VEL) of the motor vehicle ( 2 ) is determined, - is determined depending on the roll speed (PHI_VEL) and depending on a first damping constant (C_NULL) of the roll angle (PHI). Method according to one of the preceding claims, in the - being checked whether at least one start condition (CDN) is currently fulfilled (TRUE) is - one Start roll angle (PHI_NULL) and a start pitch angle (TETA_NULL) determined if the start condition (CDN) is met (TRUE) is - of the Start roll angle (TETA_PHI) is assigned to the roll angle (PHI), - the start pitch angle (TETA_NULL) is assigned to the pitch angle (TETA). The method of claim 6, wherein - a test pitch angle (TETA_TEST) is determined Checking whether a check pitch (TETA_TEST_VEL) is smaller than a first predetermined threshold (THD_1) and / or whether a test pitch acceleration (TETA_TEST_ACC) is less than a third predetermined threshold (THD_3), - the test pitch angle (TETA_TEST) is assigned to the start pitch angle (TETA_NULL) if the check pitch speed (TETA_TEST_VEL) is less than the first predetermined threshold and / or if the test pitch acceleration (TETA_TEST_ACC) is smaller than the third predetermined threshold (THD_3). Method according to one of claims 6 or 7, in which - a test roll angle (PHI_TEST) is determined Checking whether a test roll rate (PHI_TEST_VEL) is smaller than a second threshold (THD_2) and / or if one Test roll acceleration (TETA_TEST_ACC) is less than a fourth threshold (THD_4), - the test roll angle (PHI_TEST) is assigned to the start roll angle (PHI_NULL) if the test roll rate (TETA_TEST_VEL) is smaller than the second threshold (THD_2) or if the test roll acceleration (PHI_TEST_ACC) is less than the fourth threshold (THD_4). Method according to one of Claims 6 to 8, in which the starting pitch angle (TETA_NULL) depends on a longitudinal acceleration (ACC_STR) of the motor vehicle ( 2 ) and dependent on a gravitational acceleration (G) is determined. Method according to one of claims 6 to 8, in which the starting roll angle (PHI_NULL) depends on a longitudinal acceleration (ACC_STR) of the motor vehicle ( 2 ), a lateral acceleration (ACC_DIAG) of the motor vehicle ( 2 ) and dependent on a gravitational acceleration (G) is determined. Device for determining an orientation of a motor vehicle ( 2 ) represented by a pitch angle (TETA) and a roll angle (PHI), which is designed to detect a pitch rate (OMEGA_TETA), a roll rate (OMEGA_PHI) and a yaw rate (OMEGA_GIER) of the motor vehicle ( 2 ), - determining the pitch angle (TETA) of the motor vehicle ( 2 ) depending on the detected pitch rate (OMEGA_TETA) and the detected yaw rate (OMEGA_GIER), - determining the roll angle (PHI) of the motor vehicle ( 2 ) depending on the detected pitch rate (OMEGA_TETA), the detected roll rate (OMEGA_PHI), the detected yaw rate (OMEGA_GIER) and the detected pitch angle (TETA). Device for determining an orientation of a motor vehicle ( 2 ) represented by a pitch angle (TETA) and a roll angle (PHI), which is designed to detect a pitch rate (OMEGA_TETA), a roll rate (OMEGA_PHI) and a yaw rate (OMEGA_GIER) of the motor vehicle ( 2 ), - determining the roll angle (PHI) of the motor vehicle ( 2 ) depending on the detected pitch rate (OMEGA_TETA), the detected roll rate (OMEGA_PHI) and the detected yaw rate (OMEGA_GIER), - determining the pitch angle (TETA) of the motor vehicle ( 2 ) depending on the detected pitch rate (OMEGA_TETA), the detected yaw rate (OMEGA_GIER) and the determined roll angle (PHI).