Method for determining correction values, method for determining a position of a motor vehicle

Abstract

The disclosure relates to a method for determining correction values for a number of sensors of a traveling motor vehicle. The method being based on backward calculation. The disclosure further relates to a method for determining a position of a motor vehicle, using the correction values. The disclosure also relates to an associated electronic control device and to an associated non-volatile computer-readable storage medium.

Claims

1. A method of determining a position of a motor vehicle via backward calculation, the method comprising: determining a first position of the motor vehicle at a first time by satellite navigation; recording between the first time and a second time sensor data of a sensor for determining the position of the vehicle, wherein the second time is later in time than the first time; determining a second position of the motor vehicle at the second time by satellite navigation; calculating a backwardly calculated value of the first position based on the second position and the sensor data recorded between the first time and the second time; determining a deviation between the backwardly calculated value of the first position and the first position; calculating a backward correction value of the sensor based on the deviation; and determining the position of the motor vehicle based on corrected sensor data of the sensor corrected based on the backward correction value.

2. The method of claim 1, wherein the sensor comprises at least one of: a steering angle sensor, a steering wheel angle sensor, a turning rate sensor, a speed sensor, an acceleration sensor, a wheel speed sensor, a vehicle dynamics sensor, and an environment sensor.

3. The method of claim 1, further comprising: calculating a forecast of the second position based on the first position and the sensor data recorded between the first time and the second time; determining a deviation between the forecast of the second position and the second position; calculating a forward correction value of the sensor based on the deviation between the forecast of the second position and the second position; and determining the position of the motor vehicle based on corrected sensor data of the sensor corrected based on the forward correction value and the backward correction value.

4. The method of claim 3, wherein determining the position of the motor vehicle based on the corrected sensor data of the sensor corrected based on the forward correction value and the backward correction value comprises: weighting the forward correction value and the backward correction value; and determining the position of the motor vehicle base on the weighted forward correction value and the weighted backward correction value.

Description

DESCRIPTION OF DRAWINGS

(1) FIG. 1 shows a motor vehicle 10 which is configured to execute a method according to the disclosure according to an exemplary embodiment.

(2) Like reference symbols in the various drawings indicate like elements.

DETAILED DESCRIPTION

(3) In some implementations, a motor vehicle 10 is moving in the usual way on the Earth's surface. Four satellites 20, 21, 22, 23 are further shown purely schematically, which emit satellite navigation signals in the known way. The motor vehicle 10 is represented here purely schematically.

(4) The motor vehicle 10 includes an electronic control device 30. The motor vehicle 10 additionally includes a sensor 40 which is only represented here by way of example and schematically, which may be a turning rate sensor. The motor vehicle 10 also includes a satellite navigation module 50 which is configured to receive the satellite navigation signals of the satellites 20, 21, 22, 23 and, based thereon, to calculate a position of the motor vehicle 10.

(5) The control device 30, the sensor 40 and the satellite navigation module 50 are connected to one another in data terms, as shown, so that they can exchange respective values.

(6) During the normal operation of the motor vehicle 10, positions are reported at regular intervals of time by the satellite navigation module 50 to the control device 30. However, this determination of the position is not sufficient for many applications. Therefore, odometry is additionally used, sensor data of the sensor 40 and also further sensors being continuously captured and intermediate positions between the positions reported by the satellite navigation module 50 being calculated. To this end, forward calculation is made based on the last existing satellite-determined position in each case by odometry. When a new position is available again, which has been determined by the satellite navigation, the position calculated by the odometry and the position determined by the satellite navigation are compared to one another and a deviation is ascertained. Based on this deviation, a correction value of the sensor 40 is calculated, which reproduces static and dynamic errors and which can be used for the further odometry.

(7) It has now been shown that, in some cases, this type of calculation of correction values is too inaccurate. This is, for example, the case when the motor vehicle 10 exits from a tunnel, in which there was no satellite reception. In this case, the control device 30 detects that the accuracy is below a threshold, and a further determination of correction values is switched on, which is based on backward calculation. To this end, a retrodiction of a previous position is calculated in each case starting from a position determined by satellite navigation by odometry, and this retrodiction is then compared with a position which has previously been determined by satellite navigation. Based thereon, a correction value for the sensor 40 is calculated, which is then averaged in accordance with its estimated accuracy and an accuracy estimated during forward calculation, weighted with a correction value obtained from forward calculation. As a result, a definitive correction value is obtained, which is available for the further odometry and is more accurate than if this had only been calculated by forward calculation. This makes it possible, for example, at tunnel exits or in other situations in which satellite reception is suddenly available again, to return to a reliable odometry more quickly.

(8) It is understood that the sensor 40 shown here simply schematically represents a plurality of possible sensors to which the method according to the disclosure can be applied.

(9) The indicated steps of the method according to the disclosure can be executed in the indicated order. They can, however, also be executed in another order. The method according to the disclosure may be executed in one of its embodiments, for example with a specific combination of steps, such that no further steps are executed. However, further steps can essentially also be executed, including those which are not indicated.

(10) The claims which form part of the application do not constitute a waiver of the attainment of more extensive protection.

(11) If in the course of the proceedings it transpires that a feature or a group of features is not absolutely necessary, then the applicant here and now seeks a wording of at least one independent claim, no longer comprising the feature or the group of features.

(12) This may, for example, involve a sub-combination of a claim existing as at the application date or a sub-combination of a claim existing as at the application date restricted by further features. Such claims or combinations of features, which are to be newly worded, are understood to also be covered by the disclosure of this application.

(13) It is further pointed out that configurations, features and variants of the disclosure which are described in the various embodiments or exemplary embodiments and/or shown in the figures, can be combined with one another as desired. Individual or multiple features are interchangeable as desired. Resulting combinations of features are understood to also be covered by the disclosure of this application.

(14) Back references in dependent claims should not be construed as a waiver of the right to independent, objective protection for the features of the subclaims referred back to. These features can also be used in any combination with other features.

(15) Features which are only disclosed in the description or features which are disclosed in the description or a claim only in conjunction with other features can, in principle, be of independent inventive relevance. They can therefore also be included separately in claims to distinguish from the prior art.

(16) A number of implementations have been described. Nevertheless, it will be understood that various modifications may be made without departing from the spirit and scope of the disclosure. Accordingly, other implementations are within the scope of the following claims.