Method for operating a sensor system and sensor system

• US 7,800,525 B2
• Filed: 11/18/2008
• Issued: 09/21/2010
• Est. Priority Date: 12/11/2007
• Status: Active Grant

• Current Assignee: Robert Bosch GmbH
• Original Assignee: Robert Bosch GmbH
• Inventors: Beer, Leopold, Beseke, Lars
• Primary Examiner(s): JEANGLAUDE, JEAN BRUNER
• Application Number:
  US12/313,318
• Publication Number:
  US 20090146858A1
• Time in Patent Office: 672 Days
• Field of Search: 341/155, 348/277, 348/372, 348/362, 348/294, 382/100
• US Class Current: 341/155
• CPC Class Codes: B60R 21/01 Electrical circuits for triggering passive safety arrangements, e.g. airbags, safety belt tighteners, in case of vehicle accidents or impending vehicle accidents electrical circuits for transmission of signals between steering wheel and the vehicle itself B60R16/027; for electrically actuating belt retractor locking means B60R22/343
• CPC Class Codes: B60T 8/171 Detecting parameters used in the regulation; Measuring values used in the regulation
• CPC Class Codes: B60W 30/08 Active safety systems predicting or avoiding probable or impending collision or attempting to minimise its consequences
• CPC Class Codes: G01D 3/032 affecting incoming signal, e.g. by averaging; gating undesired signals
• CPC Class Codes: G01P 15/00 Measuring acceleration; Measuring deceleration; Measuring shock, i.e. sudden change of acceleration
• CPC Class Codes: H03M 1/1255 Synchronisation of the sampling frequency or phase to the input frequency or phase

Abstract

A method is provided for operating a sensor system having a sensor, an analog-to-digital converter and a digital signal-processing device, an analog signal from the sensor being transmitted to the analog-to-digital converter, the analog signal being converted to a digital signal by the analog-to-digital converter with a sampling frequency, the digital signal being transmitted to the digital signal-processing device, and the analog signal further being transmitted to a clock generator, the sampling frequency of the analog-to-digital converter being controlled by the clock generator as a function of the analog signal.

Claims

1. A method for operating a sensor system having a sensor, an analog-to-digital converter, and a digital signal-processing device, the method comprising:

transmitting an analog signal from the sensor to the analog-to-digital converter;

converting the analog signal to a digital signal using the analog-to-digital converter with a sampling frequency;

transmitting the digital signal to the digital signal-processing device;

further transmitting the analog signal to a clock generator; and

controlling the sampling frequency of the analog-to-digital converter with the clock generator as a function of the analog signal.

2. The method of claim 1, wherein in a first operating mode of the analog-to-digital converter, the sampling frequency is increased with a rising change rate of the analog signal and is lowered with a decreasing change rate of the analog signal.

3. The method of claim 1, wherein in a second operating mode of the analog-to-digital converter, the sampling frequency is increased with a rising maximum amplitude of the analog signal and is lowered with a decreasing maximum amplitude of the analog signal.

4. The method of claim 1, wherein in a third operating mode of the analog-to-digital converter, the sampling frequency is reduced and is set equal to zero in the event the change rate of the analog signal drops below at least one of a first threshold value and a maximum amplitude of the analog signal drops below a second threshold value.

5. The method of claim 1, wherein in a fourth operating mode of the analog-to-digital converter, the sampling frequency is increased in response to decreasing maximum amplitudes of the analog signal, while in response to rising maximum amplitudes of the analog signal, the sampling frequency is lowered.

6. The method of claim 1, wherein in a fifth operating mode of the analog-to-digital converter, the sampling frequency is controlled as a function of one of an analog signal and an integral of the analog signal against a unit of time.

7. The method of claim 1, wherein in a sixth operating mode of the analog-to-digital converter, the analog signal is a function of a speed value, and the sampling frequency is controlled as a function of the speed value.

8. The method of claim 1, wherein in a seventh operating mode of the analog-to-digital converter, the sampling frequency is controlled by a clock generator as a function of the analog signal and a further signal of the digital signal-processing device.

9. The method of claim 1, wherein at least one of the following is satisfied:

the digital signal-processing device time-averages a plurality of digital signals; and

a clock generator carries out a time averaging of the analog signal.

10. A sensor system, comprising:

a sensor;

an analog-to-digital converter;

a digital signal-processing device; and

a clock generator provided to set a first, second, third, fourth, fifth, sixth and seventh operating mode of the analog-to-digital converter;

wherein an analog signal is transmitted from the sensor to the analog-to-digital converter, the analog signal is converted to a digital signal using the analog-to-digital converter with a sampling frequency, the digital signal is transmitted to the digital signal-processing device, the analog signal is further transmitted to a clock generator, and the sampling frequency of the analog-to-digital converter is controlled with the clock generator as a function of the analog signal.

11. The sensor system of claim 10, wherein the sensor system is integrated into at least one of an electronic safety system, a stability system and a comfort and convenience system of a vehicle.

12. The sensor system of claim 10, wherein the sensor system is used for a readout of at least one of a yaw-rate sensor and an inertial sensor.

13. The system of claim 10, wherein in a first operating mode of the analog-to-digital converter, the sampling frequency is increased with a rising change rate of the analog signal and is lowered with a decreasing change rate of the analog signal.

14. The system of claim 10, wherein in a second operating mode of the analog-to-digital converter, the sampling frequency is increased with a rising maximum amplitude of the analog signal and is lowered with a decreasing maximum amplitude of the analog signal.

15. The system of claim 10, wherein in a third operating mode of the analog-to-digital converter, the sampling frequency is reduced and is set equal to zero in the event the change rate of the analog signal drops below at least one of a first threshold value and a maximum amplitude of the analog signal drops below a second threshold value.

16. The system of claim 10, wherein in a fourth operating mode of the analog-to-digital converter, the sampling frequency is increased in response to decreasing maximum amplitudes of the analog signal, while in response to rising maximum amplitudes of the analog signal, the sampling frequency is lowered.

17. The system of claim 10, wherein in a fifth operating mode of the analog-to-digital converter, the sampling frequency is controlled as a function of one of an analog signal and an integral of the analog signal against a unit of time.

18. The system of claim 10, wherein in a sixth operating mode of the analog-to-digital converter, the analog signal is a function of a speed value, and the sampling frequency is controlled as a function of the speed value.

19. The system of claim 10, wherein in a seventh operating mode of the analog-to-digital converter, the sampling frequency is controlled by a clock generator as a function of the analog signal and a further signal of the digital signal-processing device.