Object classification method, parking assistance method, and parking assistance system

• US 8,310,376 B2
• Filed: 07/18/2008
• Issued: 11/13/2012
• Est. Priority Date: 09/05/2007
• Status: Active Grant

• Current Assignee: ISP Investments, Inc. (Ashland Global Holdings, Inc.), Robert Bosch GmbH
• Original Assignee: Robert Bosch GmbH
• Inventors: Frank, Michael, Faber, Petko
• Primary Examiner(s): POPE, DARYL C
• Application Number:
  US12/733,458
• Publication Number:
  US 20100302069A1
• Time in Patent Office: 1,579 Days
• Field of Search: 340/932.2, 340/903, 340/933, 340/425.5, 340/435, 340/436, 340/437
• US Class Current: 340/932.2
• CPC Class Codes: G01S 15/931 of land vehicles
• CPC Class Codes: G01S 2013/9314 Parking operations
• CPC Class Codes: G01S 2013/9317 Driving backwards
• CPC Class Codes: G01S 2015/934 for measuring the depth, i.e. width, not length, of the parking space
• CPC Class Codes: G01S 7/527 Extracting wanted echo signals Doppler systems G01S15/50
• CPC Class Codes: G01S 7/539 using analysis of echo signal for target characterisation; Target signature; Target cross-section

Abstract

An object classification method in which a vehicle moves toward an object includes: (a) ascertaining a first characteristic quantity from the variation of a first signal received by a distance-measuring sensor; (b) ascertaining an additional characteristic quantity from the variation of a second signal received by the distance-measuring sensor; (c) ascertaining a distance traveled by the vehicle between step (a) and step (b); (d) ascertaining a predictive quantity associated with the distance ascertained in step (c); (e) comparing the predictive quantity with the additional characteristic quantity; and (f) generating an object classification signal.

Claims

1. An object classification method for classifying an object during a parking operation involving movement of a vehicle toward the object, comprising:

(a) ascertaining a first characteristic quantity from a variation of a first signal received by a distance-measuring sensor in the vehicle;

(b) ascertaining a second characteristic quantity from a variation of a second signal received by the distance-measuring sensor;

(c) ascertaining a distance traveled by the vehicle between step (a) and step (b);

(d) ascertaining a predictive quantity from the ascertained first characteristic quantity, wherein the predictive quantity is associated with the distance ascertained in step (c);

(e) comparing the predictive quantity with the second characteristic quantity ascertained in step (b); and

(f) generating an object classification signal associated with the object, wherein the object classification signal has a first state if the predictive quantity is less than the second characteristic quantity or a second state if the predictive quantity is greater than or equal to the second characteristic quantity.

2. The method as recited in claim 1, wherein steps (b) through (f) are repeated periodically.

3. The method as recited in claim 2, further comprising:

ascertaining whether a series of consecutively ascertained characteristic quantities has a local maximum,

wherein the object classification signal associated with the object is generated to have the first state if the series of consecutively ascertained characteristic quantities has a local maximum.

4. The method as recited in claim 1, wherein in step (d) the predictive quantity is ascertained by mathematically linking the first characteristic quantity to an attenuation factor.

5. The method as recited in claim 4, wherein in step (d) the predictive quantity is determined by multiplying the first characteristic quantity ascertained in step (a) by a factor e^kx, k being the attenuation factor and x being the distance ascertained in step (c).

6. The method as recited in claim 5, wherein the attenuation factor k is set as a function of weather conditions.

7. The method as recited in claim 1, wherein the first characteristic quantity defines the amplitude of a local maximum in the first signal received by the sensor, and wherein the second characteristic quantity defines the amplitude of a local maximum in the second signal received by the sensor.

8. The method as recited in claim 1, further comprising:

determining an instantaneous distance of the vehicle from the object; and

outputting a warning signal if the instantaneous distance is less than a predetermined minimum distance, wherein the predetermined minimum distance is a function of the state of the object classification signal.

9. A non-transitory computer-readable storage medium storing a computer program having program codes which, when executed on a computer, control a method of classifying an object during a parking operation involving movement of a vehicle toward the object, the method comprising:

(a) ascertaining a first characteristic quantity from a variation of a first signal received by a distance-measuring sensor in the vehicle;

(b) ascertaining a second characteristic quantity from a variation of a second signal received by the distance-measuring sensor;

(c) ascertaining a distance traveled by the vehicle between step (a) and step (b);

(d) ascertaining a predictive quantity from the ascertained first characteristic quantity, wherein the predictive quantity is associated with the distance ascertained in step (c);

(e) comparing the predictive quantity with the second characteristic quantity ascertained in step (b); and

(f) generating an object classification signal associated with the object, wherein the object classification signal has a first state if the predictive quantity is less than the second characteristic quantity or a second state if the predictive quantity is greater than or equal to the second characteristic quantity.

10. A parking assistance system for aiding a parking operation of a vehicle involving movement of the vehicle toward an object, comprising:

a distance-measuring sensor configured to periodically transmit a signal from the vehicle toward the object and receive a reflected signal from the object; and

a program-controlled device configured to;

ascertain a first characteristic quantity from a variation of a first signal received by the distance-measuring sensor;

ascertains a second characteristic quantity from a variation of a second signal received by the distance-measuring sensor;

ascertain a distance traveled by the vehicle between the points in time when the first and the second characteristic quantities are ascertained;

ascertain a predictive quantity from the first ascertained characteristic quantity, wherein the predictive quantity is associated with the ascertained distance traveled by the vehicle;

compares the predictive quantity with the second characteristic quantity; and

generate an object classification signal associated with the object, wherein the object classification signal has a first state if the predictive quantity is less than the second characteristic quantity or a second state if the predictive quantity is greater than or equal to the second characteristic quantity.

11. The parking assistance system as recited in claim 10, wherein the distance-measuring sensor is located in one of a rear area or a front area of the vehicle.