Driver assistance system and method for operating same

• US 9,000,902 B2
• Filed: 07/24/2008
• Issued: 04/07/2015
• Est. Priority Date: 09/24/2007
• Status: Active Grant

• Current Assignee: Robert Bosch GmbH
• Original Assignee: Robert Bosch GmbH
• Inventors: Eckel, Matthias, Hoetzel, Juergen
• Primary Examiner(s): Zimmerman, Brian
• Assistant Examiner(s): Nguyen, An T
• Application Number:
  US12/676,464
• Publication Number:
  US 20100277297A1
• Time in Patent Office: 2,448 Days
• Field of Search: 340/3.32, 340/435, 340/436, 340/438, 340/506, 340/507, 340/541, 340/901, 340/903, 340/942, 340/943, 340/286.05, 340/431, 340/463, 340/904, 340/932.2, 342/118, 342/70, 367/87, 367/99, 367/107, 367/907, 701/301, 180/169
• US Class Current: 340/435
• CPC Class Codes: G01S 13/878 Combination of several spaced transmitters or receivers of known location for determining the position of a transponder or a reflector G01S13/874 takes precedence
• CPC Class Codes: G01S 13/931 of land vehicles
• CPC Class Codes: G01S 15/876 Combination of several spaced transmitters or receivers of known location for determining the position of a transponder or a reflector G01S15/872 takes precedence
• CPC Class Codes: G01S 15/931 of land vehicles
• CPC Class Codes: G01S 2013/9314 Parking operations
• CPC Class Codes: G01S 2013/9324 Alternative operation using ultrasonic waves
• CPC Class Codes: G01S 2013/93271 in the front of the vehicles
• CPC Class Codes: G01S 2013/93272 in the back of the vehicles
• CPC Class Codes: G01S 2013/93274 on the side of the vehicles
• CPC Class Codes: G01S 2013/93275 in the bumper area
• CPC Class Codes: G01S 2015/938 in the bumper area radar in bumper area G01S2013/93275; bumper with obstacle sensor of electric or electronic type B60R19/483
• CPC Class Codes: G01S 7/0235 Avoidance by time multiplex
• CPC Class Codes: G01S 7/524 Transmitters
• CPC Class Codes: G01S 7/526 Receivers

Abstract

A driver assistance system and method for operating a driver assistance system, the driver assistance system provides a plurality of distance sensors, in particular ultrasonic sensors, which are spatially distributed and communicate with each other with the aid of a data bus. The sensors have an identical design and may be initialized by themselves using a method without a control unit and may synchronize the distance detection among themselves. The overall result of a measurement of the sensors is supplied to an output unit and displayed to the driver.

Claims

1. A driver assistance system for detecting surroundings of a motor vehicle, comprising:

at least two sensors to transmit wireless signals and to detect any reflected echo signals, the sensors having an identical design, each of the sensors having an analyzer unit to ascertain a signal propagation time, and a comparator module for comparing the ascertained signal propagation time with that ascertained by at least one preceding sensor in a bus system wherein the sensors are connected to each other via the bus system;

an output/display unit to transmit a result of the detection of the surroundings to a driver, the sensors being connected to the output/display unit via the bus system;

wherein each of the analyzer units has a conversion module to ascertain an object distance from the signal propagation time;

wherein each sensor evaluates the object distance and each sensor identifies its detection result in a data message via the bus system such that the data message includes all detection results of all the sensors, and each subsequent sensor compares by the comparator module its own detection result with one of;

(i) all the detection results of all the sensors;

or (ii) only with an identified minimum object distance ascertained from the conversion module; and

wherein the data message is modified when the detection result is less than the other detection results or the minimum object distance.

2. The driver assistance system as recited in claim 1, wherein each of the analyzer units has a comparator module to compare an object distance ascertained in the corresponding sensor.

3. The driver assistance system as recited in claim 1, wherein each of the analyzer units has a comparator module to compare the signal propagation time with a value, ascertained by other sensors.

4. The driver assistance system as recited in claim 1, wherein each of the analyzer units has a limiting value comparator module to compare an object distance ascertained in the corresponding sensor with a limiting value associated with the corresponding sensor.

5. The driver assistance system as recited in claim 1, wherein each of the sensors has a microprocessor, a module to activate and read a transducer, and a bus driver module.

6. The driver assistance system as recited in claim 5, wherein each of the sensors has a data memory unit.

7. The driver assistance system as recited in claim 5, wherein the sensors are each connected to a central data memory unit.

8. The driver assistance system as recited in claim 7, wherein the central data memory unit is integrated into a data processing system of the motor vehicle, which performs functions other than that of the driver assistance system.

9. The driver assistance system as recited in claim 1, wherein the sensors have ultrasonic transducers.

10. The driver assistance system as recited in claim 1, wherein at least two sensors are provided.

11. The driver assistance system as recited in claim 10, wherein at least ten sensors are provided.

14. The driver assistance system as recited in claim 1, wherein each of the sensors further includes a transducer module for:

reading a minimum object distance from a data message transmitted over the bus system from a preceding sensor to a current sensor in the bus system, the data message containing the minimum object distance as calculated by at least one preceding sensor in the bus system;

transmitting an updated minimum object distance as part of the data message to a next sensor in the bus system when an object distance ascertained by the current sensor is less than the read minimum object distance; and

otherwise transmitting the read minimum object distance to the next sensor in the bus system as part of the data message.

15. The driver assistance system as recited in claim 1, wherein each of the sensors further includes a transducer module for:

reading a minimum signal propagation time from a data message transmitted over the bus system from a preceding sensor to a current sensor in the bus system, the data message containing the minimum signal propagation time as determined by a plurality of preceding sensors in the bus system;

transmitting an updated minimum signal propagation time as part of the data message to a next sensor in the bus system when the signal propagation time ascertained by the current sensor is less than the read minimum signal propagation time; and

otherwise transmitting the read minimum signal propagation time to the next sensor in the bus system as part of the data message.

12. A method for operating a driver assistance system having at least two sensors for transmitting wireless signals and for detecting any reflected echo signals, all sensors having a same design and each sensor having a transducer and an analyzer unit for determining a propagation time of a signal, and the sensors being connected to each other and to an output unit with the aid of a bus system, the method comprising:

performing, by each of the sensors, a propagation time measurement;

determining, by each of the sensors, a propagation time;

relaying, by each of the sensors, a detection result to at least one other sensor;

comparing, at each of the sensors, the detection result of the respective sensor to the detection result relayed from at least one preceding sensor in the bus system;

selecting one of the compared detected results based on the comparing; and

transmitting a result of the selection to a next sensor in the bus system;

wherein each of the analyzer units has a conversion module to ascertain an object distance from the signal propagation time;

wherein each sensor evaluates the object distance and each sensor identifies its detection result in a data message via the bus system such that the data message includes all detection results of all the sensors, and each subsequent sensor compares by the comparator module its own detection result with one of;

(i) all the detection results of all the sensors;

or (ii) only with an identified minimum object distance ascertained from the conversion module; and

wherein the data message is modified when the detection result is less than the other detection results or the minimum object distance.

13. A method for operating a driver assistance system having at least two sensors for transmitting wireless signals and for detecting any reflected echo signals, all sensors having a same design and each sensor having a transducer and an analyzer unit for determining a propagation time of a signal, and the sensors being connected to each other and to an output unit with the aid of a bus system, the method comprising:

performing, by each of the sensors, a propagation time measurement;

ascertaining, by each of the sensors, a propagation time;

comparing, at each of the sensors, the ascertained propagation time with that ascertained by at least one preceding sensor in a bus system;

determining from the comparing a limiting value associated with the compared propagation times; and

transmitting the result of the determining, together with at least one ascertained propagation time, to at least one other sensor in the bus system;

wherein each of the analyzer units has a conversion module to ascertain an object distance from the signal propagation time;

wherein each sensor evaluates the object distance and each sensor identifies its detection result in a data message via the bus system such that the data message includes all detection results of all the sensors, and each subsequent sensor compares by the comparator module its own detection result with one of;

(i) all the detection results of all the sensors;

or (ii) only with an identified minimum object distance ascertained from the conversion module; and

wherein the data message is modified when the detection result is less than the other detection results or the minimum object distance.