Vehicle running control apparatus, vehicle running control method, and computer program product having the method stored therein

• US 6,311,121 B1
• Filed: 01/15/1999
• Issued: 10/30/2001
• Est. Priority Date: 01/19/1998
• Status: Expired due to Fees

• Current Assignee: Hitachi, Ltd.
• Original Assignee: Hitachi, Ltd.
• Inventors: Endo, Yoshinori, Nakamura, Kozo, Minowa, Toshimichi, Kuroda, Hiroshi, Kayano, Mitsuo, Kuragaki, Satoru, Takano, Kazuaki
• Primary Examiner(s): LOUIS JACQUES, JACQUES H
• Application Number:
  US09/231,661
• Time in Patent Office: 1,019 Days
• Field of Search: 701/96, 701/93, 701/97, 701/300, 701/301, 180/168, 180/169, 340/903, 340/904, 340/435, 340/436, 340/942, 340/438, 123/352, 342/70, 342/72, 342/73, 342/82, 342/111, 342/116, 342/104, 342/115, 342/159, 348/118, 348/148, 356/497, 356/358
• US Class Current: 701/96
• CPC Class Codes: B60K 31/0008 including means for detecting potential obstacles in vehicle path
• CPC Class Codes: G01S 13/584 adapted for simultaneous range and velocity measurements

Abstract

In a vehicle running control apparatus and method, the change of a difference in frequency between an electromagnetic wave signal transmitted from a vehicle and an electromagnetic wave signal reflected from an object is detected. Information inclusive of a distance between the object and the vehicle and a relative speed of one of the object and the vehicle to the other is generated on the basis of the change in frequency difference. A desired speed is generated on the basis of the generated information and information of the running of the vehicle so that the change in frequency difference is generated. A signal for control of the speed of the vehicle is generated on the basis of the desired speed.

Claims

1. A vehicle running control apparatus comprising:

detection means for detecting the change of a difference in frequency between an electromagnetic wave signal transmitted from a vehicle and an electromagnetic wave signal having a Doppler shift reflected from an object and generating information inclusive of a distance between said object and said vehicle and a relative speed of one of said object and said vehicle to the other on the basis of said change in frequency difference;

desired speed generation means for generating a desired speed on the basis of said information generated by said detection means and information of the running of said vehicle so that said change in frequency difference is generated;

speed control means for generating a signal for control of the speed of said vehicle on the basis of said desired speed;

wherein said desired speed generation means sets said desired speed so that the detected relative speed takes a value in a predetermined range unequal to zero; and

wherein said desired speed generation means includes means for setting a time-dependent changing desired speed when the detected relative speed comes to the value in the predetermined range unequal to zero.

2. A vehicle running control apparatus according to claim 1, wherein said time-dependent changing desired speed includes one or more sine signals.

3. A vehicle running control apparatus according to claim 1, wherein said speed control means determines said desired speed on the basis of the speed of said vehicle, the detected relative speed and a difference between a required distance and the detected distance between said object and said vehicle.

4. A vehicle running control apparatus according to claim 1, further comprising means for determining a desired driving torque value for said vehicle corresponding to said desired speed.

5. A vehicle running control apparatus according to claim 4, further comprising means for performing the control of a throttle opening angle, a transmission and a brake of an engine mounted on said vehicle in accordance with said desired driving torque value.

6. A vehicle running control apparatus comprising:

detection means for detecting the change of a difference in frequency between an electromagnetic wave signal transmitted from a vehicle and an electromagnetic wave signal having a Doppler shift reflected from an object and generating information inclusive of a distance between said object and said vehicle and a relative speed of one of said object and said vehicle to the other on the basis of said change in frequency difference;

desired speed generation means for generating a desired speed on the basis of said information generated by said detection means and information of the running of said vehicle so that said change in frequency difference is generated;

speed control means for generating a signal for control of the speed of said vehicle on the basis of said desired speed;

wherein said desired speed generation means sets said desired speed so that the detected relative speed takes a value in a predetermined range unequal to zero; and

wherein said desired speed generation means includes means for setting a time-dependent changing desired speed when a difference between said distance between said object and said vehicle and a predetermined required distance becomes smaller than a reference value.

7. A vehicle running control apparatus according to claim 6, wherein said time-dependent changing desired speed includes one or more sine signals.

8. A vehicle running control apparatus comprising:

detection means for detecting the change of a difference in frequency between an electromagnetic wave signal transmitted from a vehicle and an electromagnetic wave signal having a Doppler shift reflected from an object and generating information inclusive of a distance between said object and said vehicle and a relative speed of one of said object and said vehicle to the other on the basis of said change in frequency difference;

desired speed generation means for generating a desired speed on the basis of said information generated by said detection means and information of the running of said vehicle so that said change in frequency difference is generated;

speed control means for generating a signal for control of the speed of said vehicle on the basis of said desired speed; and

further comprising means for setting a required distance between said object and said vehicle from at least the speed of said vehicle, said desired speed generation means including means for setting a first desired speed and a desired speed for correction on the basis of the speed of said vehicle, the detected relative speed, said required distance and the detected distance between said object and said vehicle, and said speed control means controlling the speed of said vehicle on the basis of said first desired speed when the absolute value of said detected relative speed is larger than a reference value and on the basis of the sum of said first desired speed and said desired speed for correction when the absolute value of said detected relative speed is not larger than said reference value.

9. A vehicle running control apparatus according to claim 8, wherein said desired speed for correction includes a time-dependent changing desired speed signal.

10. A vehicle running control apparatus according to claim 9, wherein said time-dependent changing desired speed signal includes one or more sine signals.

11. A vehicle running control apparatus according to claim 10, wherein said desired speed for correction is represented by the equation of $\Delta$



 



Vd=Vmax

∑

i=0n

 



{(1/ω

i)

sin

 



(ω

i

t+θ

i)}

where Δ

V_d is the desired speed for correction, V_max is the maximum speed for correction, ω

_i is the angular frequency, t is a time from the setting of the desired speed for correction, θ

_i is an initial phase difference, and n is any integer equal to or larger than 0.

12. A vehicle running control apparatus comprising:

detection means for detecting the change of a difference in frequency between an electromagnetic wave signal transmitted from a vehicle and an electromagnetic wave signal having a Doppler shift reflected from an object and generating information inclusive of a distance between said object and said vehicle and a relative speed of one of said object and said vehicle to the other on the basis of said change in frequency difference;

desired speed generation means for generating a desired speed on the basis of said information generated by said detection means and information of the running of said vehicle so that said change in frequency difference is generated;

speed control means for generating a signal for control of the speed of said vehicle on the basis of said desired speed; and

further comprising means for setting a required distance between said object and said vehicle from at least the speed of said vehicle, said desired speed generation means including means for setting a first desired speed and a desired speed for correction on the basis of the speed of said vehicle, the detected relative speed, said required distance and the detected distance between said object and said vehicle, and said speed control means controlling the speed of said vehicle on the basis of said first desired speed when the absolute value of a difference between said detected distance and said required distance is larger than a reference value on the basis of the sum of said first desired speed and said desired speed for correction when the absolute value of said difference is not larger than said reference value.

13. A vehicle running control apparatus according to claim 12, wherein said desired speed for correction includes a time-dependent changing desired speed signal.

14. A vehicle running control apparatus according to claim 13, wherein said time-dependent changing desired speed signal includes one or more sine signals.

15. A vehicle running control apparatus according to claim 14, wherein said desired speed for correction is represented by the equation of $\Delta$



 



Vd=Vmax

∑

i=0n

 



{(1/ω

i)

sin

 



(ω

i

t+θ

i)}

where Δ

V_d is the desired speed for correction, V_max is the maximum speed for correction, ω

_i is the angular frequency, t is a time from the setting of the desired speed for correction, θ

_i is an initial phase difference, and n is any integer equal to or larger than 0.

16. A vehicle running control apparatus comprising:

detection means for detecting the change of a difference in frequency between an electromagnetic wave signal transmitted from a vehicle and an electromagnetic wave signal having a Doppler shift reflected from an object and generating information inclusive of a distance between said object and said vehicle and a relative speed of one of said object and said vehicle to the other on the basis of said change in frequency difference;

desired speed generation means for generating a desired speed on the basis of said information generated by said detection means and information of the running of said vehicle so that said change in frequency difference is generated;

speed control means for generating a signal for control of the speed of said vehicle on the basis of said desired speed; and

further comprising means for setting a required distance between said object and said vehicle from at least the speed of said vehicle and means for setting a required distance for correction, said desired speed generation means including means for setting said desired speed on the basis of the speed of said vehicle, the detected relative speed, and a deviation between said required distance and the detected distance between said object and said vehicle so that when the absolute value of said detected relative speed is not larger than a reference value, said desired speed is set taking as said deviation a difference between the sum of said required distance and said required distance for correction and said detected distance.

17. A vehicle running control apparatus according to claim 16, wherein said required distance for correction includes a time-dependent changing required distance signal.

18. A vehicle running control apparatus according to claim 17, wherein said time-dependent changing required distance signal includes one or more sine signals.

19. A vehicle running control apparatus according to claim 18, wherein said required distance for correction is represented by the equation of $\Delta$



 



Dr=Dmax

∑

i=0n

 



{(1/ω

i)

sin

 



(ω

i

t+θ

i)}

where Δ

D_r is the required distance for correction, D_max is the maximum distance for correction, ω

_i is the angular frequency, t is a time from the setting of the required distance for correction, θ

_i is an initial phase difference, and n is any integer equal to or larger than 0.

20. A vehicle running control apparatus comprising:

detection means for detecting the change of a difference in frequency between an electromagnetic wave signal transmitted from a vehicle and an electromagnetic wave signal having a Doppler shift reflected from an object and generating information inclusive of a distance between said object and said vehicle and a relative speed of one of said object and said vehicle to the other on the basis of said change in frequency difference;

desired speed generation means for generating a desired speed on the basis of said information generated by said detection means and information of the running of said vehicle so that said change in frequency difference is generated;

speed control means for generating a signal for control of the speed of said vehicle on the basis of said desired speed; and

further comprising means for setting a required distance between said object and said vehicle from at least the speed of said vehicle and means for setting a required distance for correction, said desired speed generation means including means for setting said desired speed on the basis of the speed of said vehicle, the detected relative speed, and a deviation between said required distance and the detected distance between said object and said vehicle so that when the absolute value of said deviation is not larger than a reference value, said desired speed is set taking as said deviation a difference between the sum of said required distance and said required distance for correction and said detected distance.

21. A vehicle running control apparatus according to claim 20, wherein said required distance for correction includes a time-dependent changing required distance signal.

22. A vehicle running control apparatus according to claim 21, wherein said time-dependent changing required distance signal includes one or more sine signals.

23. A vehicle running control apparatus according to claim 22, wherein said required distance for correction is represented by the equation of $\Delta$



 



Dr=Dmax

∑

i=0n

 



{(1/ω

i)

sin

 



(ω

i

t+θ

i)}

where Δ

D_r is the required distance for correction, D_max is the maximum distance for correction, ω

_i is the angular frequency, t is a time from the setting of the required distance for correction, θ

_i is an initial phase difference, and n is any integer equal to or larger than 0.

24. A vehicle running control method comprising:

detecting the change of a difference in frequency between an electromagnetic wave signal transmitted from a vehicle and an electromagnetic wave signal having a Doppler shift reflected from an object;

generating speed/distance information inclusive of a distance between said object and said vehicle and a relative speed of one of said object and said vehicle to the other on the basis of said change in frequency difference;

generating a desired speed on the basis of said speed/distance information and information of said vehicle so that said change in frequency difference is generated;

generating a signal for control of the speed of said vehicle on the basis of said desired speed;

wherein said desired speed is generated so that the detected relative speed takes a value in a predetermined range unequal to zero; and

wherein a time-dependent changing desired speed is set when the detected relative speed comes to the value in the predetermined range unequal to zero.

25. A vehicle running control method comprising:

detecting the change of a difference in frequency between an electromagnetic wave signal transmitted from a vehicle and an electromagnetic wave signal having a Doppler shift reflected from an object;

generating speed/distance information inclusive of a distance between said object and said vehicle and a relative speed of one of said object and said vehicle to the other on the basis of said change in frequency difference;

generating a desired speed on the basis of said speed/distance information and information of said vehicle so that said change in frequency difference is generated;

generating a signal for control of the speed of said vehicle on the basis of said desired speed;

wherein said desired speed is generated so that the detected relative speed takes a value in a predetermined range unequal to zero; and

wherein a time-dependent changing desired speed is set when a difference between said distance between said object and said vehicle and a predetermined required distance becomes smaller than a reference value.

26. A computer program product comprising a computer usable medium having computer readable program code means embodied in said medium for controlling the running of a vehicle, said computer readable program code means comprising:

means for detecting the change of a difference in frequency between an electromagnetic wave signal transmitted from a vehicle and an electromagnetic wave signal having a Doppler shift reflected from an object;

means for generating speed/distance information inclusive of a distance between said object and said vehicle and a relative speed of one of said object and said vehicle to the other on the basis of said change in frequency difference;

means for generating a desired speed on the basis of said speed/distance information and information of said vehicle so that said change in frequency difference is generated;

means for generating a signal for control of the speed of said vehicle on the basis of said desired speed;

wherein said desired speed generating means includes means for determining said desired speed so that the detected relative speed takes a value in a predetermined range unequal to zero; and

wherein said desired speed generating means includes means for generating a time-dependent changing desired speed signal when the detected relative speed comes to the value in the predetermined range unequal to zero.

27. A computer program product comprising a computer usable medium having computer readable program code means embodied in said medium for controlling the running a vehicle, said computer readable program code means comprising:

means for detection the change of a difference in frequency between an electromagnetic wave signal transmitted from a vehicle and an electromagnetic wave signal having a Doppler shift reflected from an object;

means for generating speed/distance information inclusive of a distance between said object and said vehicle and a relative speed of one of said object and said vehicle to the other on the basis of said change in frequency difference;

means for generating a desired speed on the basis of said speed/distance information and information of said vehicle so that said change in frequency difference is generated;

means for generating a signal for control of the speed of said vehicle on the basis of said desired speed;

wherein said desired speed generating means includes means for determining said desired speed so that the detected relative speed takes a value in a predetermined range unequal to zero; and

wherein said desired speed generating means includes means for generating a time-dependent changing desired speed signal when a difference between said distance between said object and said vehicle and a predetermined required distance becomes smaller than a reference value.