VEHICLE COLLISION ANTICIPATING DEVICE

• US 3,864,678 A
• Filed: 04/04/1973
• Issued: 02/04/1975
• Est. Priority Date: 04/08/1972
• Status: Expired due to Term

• Current Assignee: Kazuo Sato, Minoru Bito, Osamu Ozeki, Takayuki Kato, Teruo Yamanaka
• Original Assignee: Kazuo Sato, Minoru Bito, Osamu Ozeki, Takayuki Kato, Teruo Yamanaka
• Inventors: Yamanaka, Teruo, Ozeki, Osamu, Sato, Kazuo, Bito, Minoru, Kato, Takayuki
• Primary Examiner(s): Wilbur, Maynard R.
• Assistant Examiner(s): Montone, G. E.
• Application Number:
  US05/347,776
• Time in Patent Office: 671 Days
• Field of Search: 343/7ED,112CA,9,8,5PD
• US Class Current: 342/59
• CPC Class Codes: B60R 21/013 including means for detecting collisions, impending collisions or roll-over
• CPC Class Codes: B60R 21/0134 responsive to imminent contact with an obstacle , e.g. using radar systems
• CPC Class Codes: G01S 13/931 of land vehicles
• CPC Class Codes: G01S 2013/932 using own vehicle data, e.g. ground speed, steering wheel direction
• CPC Class Codes: G01S 2013/9325 for inter-vehicle distance regulation, e.g. navigating in platoons
• CPC Class Codes: G01S 2013/93271 in the front of the vehicles

Abstract

An improvement of a vehicle collison anticipating device using transmitted and reflected frequency-modulated continuous waves is provided. A low frequency wave is produced by mixing a part of a transmitted wave and a reflected wave from an object. The low frequency wave and at least one Doppler signal obtained from the low frequency wave are signal processed so as to generate signals. A collision time which is determined by a distance between the vehicle and object and a relative velocity of the object with respect to the vehicle, is detected. An intensity of said Doppler signal is detected so as to detect the presence of the object in a predetermined detection range determined by the positions and angles of the transmitting and receiving antennas. A collision of the object against the vehicle is anticipated by detecting said collision time and said intensity of the Doppler signal.

Claims

1. A vehicle collission anticipating device comprising wave processing means for transmitting a wave by a transmitting antenna installed at a predetermined position and angle of a vehicle, for receiving a reflected wave from an object by a receiving antenna installed at predetermined position and angle of the vehicle, and for generating a low frequency wave by mixing said transmitted and reflected waves, said receiving antenna being so installed that the beam axis of said receiving antenna intersects that of said transmitting antenna in a predetermined range, analog signal processing means connected to said wave processing means for signal processing said low frequency wave into at least one Doppler signal obtained from said low frequency wave, and for generating additional signals corresponding to the intensity and frequency of the various frequency components of said low frequency wave, collision time detecting means connected to said analog signal processing means for detecting a collision time which is determined by a distance between the vehicle and object and a relative velocity of the object with respect to the vehicle in response to the additional signals from said analog signal processing means, and for generating a signal when said coLlision time reaches a predetermined time, minimum level detecting means connected to said analog signal processing means for detecting an intensity of said Doppler signal obtained from said low frequency wave, and for generating a signal when said intensity of said Doppler signal reaches a predetermined minimum level so as to detect the object to enter a predetermined detection range defined by the positions and angles of the transmitting and receiving antennas, and decision means connected to said collision time detecting means and minimum level detecting means for generating a signal in response to the simultaneous generation of signals by said collision time detecting means and minimum level detecting means, thereby anticipating a collision of the object against the vehicle.

2. A vehicle collision anticipating device as set forth in claim 1, further comprising relative velocity detecting means connected to said analog signal processing means for detecting a relative velocity of the object with respect to the vehicle in response to the additional signals for said analog signal processing means and for generating a signal when said relative velocity reaches a predetermined velocity, and wherein said decision means is further connected to said relative velocity detecting means for generating a signal in response to the simultaneous generation of signals by said collision time detecting means, minimum level detecting means and relative velocity detecting means.

3. A vehicle collision anticipating device as set forth in claim 1, further comprising direction detecting means connected to said analog signal processing means for detecting a direction of a relative movement of the object with respect to the vehicle in response to the signals from said analog signal processing means and for generating a signal when the object approaches the vehicle, and wherein said decision means is further connected to said direction detecting means for generating a signal in response to the simultaneous generation of signals by said collision time detecting means, minimum level detecting means and direction detecting means.

4. A vehicle collision anticipating device as set forth in claim 2, further comprising direction detecting means connected to said analog signal processing means for detecting a direction of a relative movement of the object with respect to the vehicle in response to the signals from said analog signal processing means and for generating a signal when the object approaches the vehicle, and wherein said decision means is further connected to said direction detecting means for generating a signal in response to the simultaneous generation of signals by said collision time detecting means, minimum level detecting means, relative velocity detecting means and direction detecting means.

5. A vehicle collision anticipating device as set forth in claim 1, further comprising distance detecting means connected to said analog signal processing means for detecting a distance between the vehicle and object in response to the signals from said analog signal processing means, and for generating a signal when the distance reaches a predetermined distance, and wherein said decision means is further connected to said distance detecting means for generating a signal in response to the simultaneous generation of signals by said minimum level detecting means, and one of said collision time detecting means and said distance detecting means.

6. A vehicle collision anticipating device as set forth in claim 4, further comprising distance detecting means connected to said analog signal processing means for detecting a distance between the vehicle and object in response to the signals from said analog signal processing means, and for generating a signal when the distance reaches a predetermined distance, and wherein said decision means is further connected to said distance detecting means for generating a signal in respOnse to the simultaneous generation of signals by said minimum level detecting means, relative velocity detecting means, direction detecting means, and one of said collision time detecting means and said distance detecting means.

7. A vehicle collision anticipating device as set forth in claim 1, wherein said collision time detecting means comprises means for detecting the distance between the vehicle and object by computing an intensity ratio between the maximum values of at least two Doppler signals for detecting the relative velocity of the object from an angular frequency of the Doppler signal, and for detecting the collision time by dividing said distance by said relative velocity.

8. A vehicle collision anticipating device as set forth in claim 2, wherein said analog signal processing means further comprises means for separating the low frequency wave into at least two frequency components and wherein said Doppler signal is derived from a lower of said frequency components and further comprises means for deriving an additional Doppler signal from a higher of said frequency components, said collision time detecting means comprises means for detecting the distance between the vehicle and object by computing an intensity ratio between the maximum values of at least said two Doppler signals, for detecting the relative velocity of the object from an angular frequency of the Doppler signal, and for detecting the collision time by dividing said distance by said relative velocity, and said relative velocity detecting means comprises means for detecting an angular frequency of one of said Doppler signals so as to detect the relative velocity of the object with respect to the vehicle.

9. A vehicle collision anticipating device as set forth in claim 3, wherein said collision time detecting means comprises means for detecting the distance between the vehicle and object by computing an intensity ratio between the maximum values of at least two of said Doppler signals for detecting the relative velocity of the object from an angular frequency of one of the Doppler signals, and for detecting the collision time by dividing said distance by said relative velocity, and said direction detecting means comprises means for detecting a phase relation between at least two of said Doppler signals so as to detect the direction of the relative movement of the object with respect to the vehicle.

10. A vehicle collision anticipating device as set forth in claim 4, wherein said collision time detecting means comprises means for detecting the distance between the vehicle and object by computing an intensity ratio between the maximum values of at least two of said Doppler signals, for detecting the relative velocity of the object from an angular frequency of one of the Doppler signals, and for detecting the collision time by dividing said distance by said relative velocity. said relative velocity detecting means comprises means for detecting an angular frequency of one of the Doppler signals so as to detect the relative velocity of the object with respect to the vehicle, and said direction detecting means comprises means for detecting a phase relation between at least two of the Doppler signals so as to detect the direction of the relative movement of the object with respect to the vehicle.

11. A vehicle collision anticipating device as set forth in claim 5, wherein said collision time detecting means comprises means for detecting the distance between the vehicle and object by computing an intensity ratio between the maximum values of at least two of the Doppler signals, for detecting the relative velocity of the object from an angular frequency of one of the Doppler signals, and for detecting the collision time by dividing said distance by said relative velocity, and said distance detecting means comprises means for calculating an intensity ratio between the maximum values of at least two of the DoppleR signals so as to detect the distance between the vehicle and object.

12. A vehicle collision anticipating device as set forth in claim 6, wherein said distance detecting means comprises means for calculating an intensity ratio between the maximum values of at least two of the Doppler signals so as to detect the distance between the vehicle and object, said collision time detecting means comprises means for detecting the distance between the vehicle and object by computing an intensity ratio between the maximum values of at least two of the Doppler signals, for detecting the relative velocity of the object from an angular frequency of one of the Doppler signals, and for detecting the collision time by dividing said distance by said relative velocity, and said relative velocity detecting means comprises means for detecting an angular frequency of one of the Doppler signals so as to detect the relative velocity of the object with respect to the vehicle, and said direction detecting means comprises means for detecting a phase relation between at least two of the Doppler signals so as to detect the direction of the relative movement of the object with respect to the vehicle.

13. A vehicle collision anticipating device as set forth in claim 7,, wherein said wave processing means comprises two wave processing units, each of said wave processing units comprising a sine wave generator, a microwave modulator connected to said sine wave generator, a microwave oscillator connected to said microwave modulator, a coupler connected to said microwave oscillator, a transmitting antenna connected to said coupler, a receiving antenna connected to said coupler, and a first mixer connected to said coupler, and the right and left transmitting and receiving antennas being so mounted on the vehicle that the beams thereof intersect each other to form the predetermined detection ranges, said analog signal processing means comprises two analog signal processing units, said collision time detecting means comprises two collision time detecting units in which said collision time is predetermined to be 100 msec, said minimum level detecting means comprises two minimum level detecting units, and said decision means comprises a decision unit for generating a signal in response to the simultaneous generation of signals by said collision time detecting units and minimum level detecting units.

14. A vehicle collision anticipating device as set forth in claim 8, wherein said wave processing means comprises two wave processing units, each of said wave processing units comprises in a sine wave generator, a microwave modulator connected to said sine wave generator, a microwave oscillator connected to said microwave modulator, a coupler connected to said microwave oscillator, a transmitting antenna connected to said coupler, a receiving antenna connected to said coupler, and a first mixer connected to said coupler, and the right and left transmitting and receiving antennas being so mounted on the vehicle that the beams thereof intersect each other to form the predetermined detection ranges, said analog signal processing means comprises two analog signal processing units, said collision time detecting means comprises two collision time detecting units in which said collision time is predetermined to be 100 msec, said minimum level detecting means comprises two minimum level detecting units, said relative velocity detecting means comprises two relative velocity detecting units in which said relative velocity is predetermined to be 30 Km/h, and said decision means comprises a decision unit for generating a signal in response to the simultaneous generation of signals by said collision time detecting units, minimum level detecting units and relative velocity detecting units.

15. A vehicle collision anticipating device as set forth in claim 9, wherein said wave processing means comprises two wave prOcessing units, each of said wave processing units comprising a sine wave generator, a microwave modulator connected to said sine wave generator, a microwave oscillator connected to said microwave modulator, a coupler connected to said microwave oscillator, a transmitting antenna connected to said coupler, a receiving antenna connected to said coupler, and a first mixer connected to said coupler, and the right and left transmitting and receiving antennas being so mounted on the vehicle that the beams thereof intersect each other to form the predetermined detection ranges, said analog signal processing means comprises two analog signal processing units, said collision time detecting means comprises two collision time detecting units in which said collision time is predetermined to be 100 msec, said minimum level detecting means comprises two minimum level detecting units, said direction detecting means comprises two direction detecting units for detecting a phase relation between at least two of the Doppler signals, and said decision means comprises a decision unit for generating a signal in response to the simultaneous generation of signals by said collision time detecting units, minimum level detecting units and direction detecting units.

16. A vehicle collision anticipating device as set forth in claim 10, wherein said wave processing means comprises two wave processing units, each of said wave processing units comprising a sine wave generator, a microwave modulator connected to said sine wave generator, a microwave oscillator connected to said microwave modulator, a coupler connected to said microwave oscillator, a transmitting antenna connected to said coupler, a receiving antenna connected to said coupler, and a first mixer connected to said coupler, and the right and left transmitting and receiving antennas being so mounted on the vehicle that the beams thereof intersect each other to form the predetermined detection ranges, said analog signal processing means comprises two analog signal processing units, said collision time detecting means comprises two collision time detecting units in which said collision time is predetermined to be 100 msec, said minimum level detecting means comprises two minimum level detecting units, said relative velocity detecting means comprises two relative velocity detecting units in which said relative velocity is predetermined to be 30 Km/h, each of said relative velocity detecting units comprises a decision time detecting circuit which is reset every 15 waves of the Doppler signal and generates a signal to said collision time detecting means in order to prevent the inadvertent operation of the vehicle collision anticipating device, said direction detecting means comprises two direction detecting units for detecting a phase relation between at least two of the Doppler signals, and said decision means comprises a decision unit for generating a signal in response to the simultaneous generation of signals by said collision time detecting units, minimum level detecting units, relative velocity detecting units and direction detecting units.

17. A vehicle collision anticipating device as set forth in claim 12, wherein said wave processing means comprises two wave processing units, each of said wave processing units comprising a sine wave generator, a microwave modulator connected to said sine wave generator, a microwave oscillator connected to said microwave modulator, a coupler connected to said microwave oscillator, a transmitting antenna connected to said coupler, a receiving antenna connected to said coupler, and a first mixer connected to said coupler, and the right and left transmitting and receiving antennas being so mounted on the vehicle that the beams thereof intersect each other to form the predetermined detection ranges, said analog signal processing means comprises two analog signal processing units, said collision time detectiNg means comprises two collision time detecting units in which said collision time is predetermined to be 100 msec, said minimum level detecting means comprises two minimum level detecting units, said relative velocity detecting means comprises two relative velocity detecting units in which said relative velocity is predetermined to be 30 Km/h, said direction detecting means comprises two direction detecting units for detecting a phase relation between at least two of the Doppler signals, said distance detecting means comprises two distance detecting units for calculating an intensity ratio between the maximum values of at least two Doppler signals, and said decision means comprises a decision unit for generating a signal in response to the simultaneous generation of signals by said minimum level detecting units, relative velocity detecting units, direction detecting units, and one of said collision time detecting units or said distance detecting units.

18. A vehicle collision anticipating device as set forth in claim 16, wherein said analog signal processing unit comprises a wide band amplifier connected to said first mixer of said wave processing unit, a first bandpass filter connected to said wide band amplifier, a first AC-DC converter connected to said first bandpass filter, a first wave shaping circuit connected to said first bandpass filter, a second mixer connected to said wide band amplifier and to said sine wave generator, a second bandpass filter connected to said second mixer, a second AC-DC converter connected to said second bandpass filter, and a second wave shaping circuit connected to said second bandpass filter, said collision time detecting unit comprises a multiplier connected to said second AC-DC converter of said analog signal processing unit and a comparator connected to said multiplier and to said first AC-DC converter, said minimum level detecting unit comprises a comparator connected to said second wave shaping circuit of said analog signal processing unit and a reference voltage source which is connected to said comparator and supplies a reference voltage, said relative velocity detecting unit comprises a first counter connected to said second wave shaping circuit of said analog signal processing unit, an RS flip-flop connected to said first counter, and AND circuit connected to said RS flip-flop, a clock pulse generator connected to said AND circuit, an OR circuit connected to said first counter, a first delay circuit connected to said OR circuit, a second delay circuit connected to said first delay circuit, a second counter connected to said AND circuit, OR circuit and second delay circuit, a register connected to said first delay circuit, said second counter and said multiplier of said collision time detecting unit a D-A converter connected to said register, and a comparator connected to said D-A converter and a reference voltage source, said direction detecting unit comprises a D-type flip-flop connected to said first and second wave shaping circuits of said analog signal processing unit, a monostable and multivibrator connected to said D-type flip-flop, an integrator connected to said monostable multivibrator, and a comparator connected to said integrator and a reference voltage source, and said decision unit comprises three AND circuits which are connected to said collision distance detecting unit, minimum level detecting unit, relative velocity detecting unit, and direction detecting unit.

19. A vehicle collision anticipating device as set forth in claim 17, wherein said analog signal processing unit comprises a wide band amplifier connected to said first mixer of said wave processing unit, a first bandpass filter connected to said wide band amplifier, a first AC-DC converter connected to said first bandpass filter, a first wave shaping circuit connected to said first bandpass filter, a second mixer connected to said wide baNd amplifier and to said sine wave generator, a second bandpass filter connected to said second mixer, a second AC-DC converter connected to said second bandpass filter, and a second wave shaping circuit connected to said second bandpass filter, said collision time detecting unit comprises a multiplier connected to said second AC-DC converter of said analog signal processing unit, and a comparator connected to said multiplier and to said first AC-DC converter said minimum level detecting unit comprises a comparator connected to said second wave shaping circuit of said analog signal processing unit and a reference voltage source which is connected to said comparator and supplies a reference voltage, said relative velocity detecting unit comprises a first counter connected to said wave shaping circuit of said analog signal processing unit, an RS flip-flop connected to said first counter, an AND circuit connected to said RS flip-flop, a clock pulse generator connected to said AND circuit, an OR circuit connected to said first counter, a first delay circuit connected to said OR circuit, a second delay circuit connected to said first delay circuit, a second counter connected to said AND circuit, OR circuit and second delay circuit, a register connected to said first delay circuit, said second counter and said multiplier of said collision time detecting unit a D-A converter connected to said register, and a comparator connected to said D-A converter and a reference voltage source, said direction detecting unit comprises a D-type flip-flop connected to said first and second wave shaping circuits of said analog signal processing unit, a monostable multivibrator connected to said D-type flip-flop, an integrator connected to said monostable multivibrator, and a comparator connected to said integrator and a reference voltage source, said distance detecting unit comprises a first comparator connected to said first and second AC-DC converters and a second comparator connected to said D-A converter, a gate circuit connected to said first and second comparators and a reference voltage source connected to said second comparator, and said decision unit comprises a first AND circuit connected to said collission time detecting unit, an OR circuit connected to said first AND circuit and to said distance detecting units, and second to fourth AND circuits respectively connected to said direction detecting units, to said minimum level detecting units and to said relative velocity detecting units, and a fifth AND circuit connected to said OR circuit and to said second to fourth AND circuits.