GB2139035A - Radar vehicle braking control - Google Patents
Radar vehicle braking control Download PDFInfo
- Publication number
- GB2139035A GB2139035A GB08307656A GB8307656A GB2139035A GB 2139035 A GB2139035 A GB 2139035A GB 08307656 A GB08307656 A GB 08307656A GB 8307656 A GB8307656 A GB 8307656A GB 2139035 A GB2139035 A GB 2139035A
- Authority
- GB
- United Kingdom
- Prior art keywords
- output
- vehicle
- frequency
- signal
- antenna
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
- 238000001514 detection method Methods 0.000 claims description 16
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 claims description 4
- 229910052782 aluminium Inorganic materials 0.000 claims description 4
- 239000004411 aluminium Substances 0.000 claims description 4
- 230000005540 biological transmission Effects 0.000 claims description 4
- 230000000007 visual effect Effects 0.000 claims description 3
- 230000000977 initiatory effect Effects 0.000 claims description 2
- 230000001419 dependent effect Effects 0.000 claims 1
- 230000007547 defect Effects 0.000 description 3
- 238000010276 construction Methods 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 230000001747 exhibiting effect Effects 0.000 description 1
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
- G01S13/00—Systems using the reflection or reradiation of radio waves, e.g. radar systems; Analogous systems using reflection or reradiation of waves whose nature or wavelength is irrelevant or unspecified
- G01S13/88—Radar or analogous systems specially adapted for specific applications
- G01S13/93—Radar or analogous systems specially adapted for specific applications for anti-collision purposes
- G01S13/931—Radar or analogous systems specially adapted for specific applications for anti-collision purposes of land vehicles
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
- G01S13/00—Systems using the reflection or reradiation of radio waves, e.g. radar systems; Analogous systems using reflection or reradiation of waves whose nature or wavelength is irrelevant or unspecified
- G01S13/02—Systems using reflection of radio waves, e.g. primary radar systems; Analogous systems
- G01S13/06—Systems determining position data of a target
- G01S13/08—Systems for measuring distance only
- G01S13/32—Systems for measuring distance only using transmission of continuous waves, whether amplitude-, frequency-, or phase-modulated, or unmodulated
- G01S13/34—Systems for measuring distance only using transmission of continuous waves, whether amplitude-, frequency-, or phase-modulated, or unmodulated using transmission of continuous, frequency-modulated waves while heterodyning the received signal, or a signal derived therefrom, with a locally-generated signal related to the contemporaneously transmitted signal
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
- G01S13/00—Systems using the reflection or reradiation of radio waves, e.g. radar systems; Analogous systems using reflection or reradiation of waves whose nature or wavelength is irrelevant or unspecified
- G01S13/88—Radar or analogous systems specially adapted for specific applications
- G01S13/93—Radar or analogous systems specially adapted for specific applications for anti-collision purposes
- G01S13/931—Radar or analogous systems specially adapted for specific applications for anti-collision purposes of land vehicles
- G01S2013/9317—Driving backwards
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
- G01S13/00—Systems using the reflection or reradiation of radio waves, e.g. radar systems; Analogous systems using reflection or reradiation of waves whose nature or wavelength is irrelevant or unspecified
- G01S13/88—Radar or analogous systems specially adapted for specific applications
- G01S13/93—Radar or analogous systems specially adapted for specific applications for anti-collision purposes
- G01S13/931—Radar or analogous systems specially adapted for specific applications for anti-collision purposes of land vehicles
- G01S2013/93185—Controlling the brakes
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
- G01S13/00—Systems using the reflection or reradiation of radio waves, e.g. radar systems; Analogous systems using reflection or reradiation of waves whose nature or wavelength is irrelevant or unspecified
- G01S13/88—Radar or analogous systems specially adapted for specific applications
- G01S13/93—Radar or analogous systems specially adapted for specific applications for anti-collision purposes
- G01S13/931—Radar or analogous systems specially adapted for specific applications for anti-collision purposes of land vehicles
- G01S2013/9327—Sensor installation details
- G01S2013/93272—Sensor installation details in the back of the vehicles
Landscapes
- Engineering & Computer Science (AREA)
- Radar, Positioning & Navigation (AREA)
- Remote Sensing (AREA)
- Physics & Mathematics (AREA)
- Electromagnetism (AREA)
- Computer Networks & Wireless Communication (AREA)
- General Physics & Mathematics (AREA)
- Radar Systems Or Details Thereof (AREA)
Abstract
In a vehicle braking control system, particularly for a giant earth moving vehicle, an F.M.C.W. radar feeds an antenna 1 at the rear of the vehicle. Reflections are received via the same antenna 1, mixed with transmitted energy to provide a difference frequency and submitted to a frequency selective receiver 5, the output of which will thereby be limited to responses within a given range behind the vehicle. Output from the receiver is passed into two channels. One channel contains a frequency-to-voltage convertor 7 followed by a threshold detector 9 which is set such that a signal is passed to an alarm output terminal 10 if a man-sized or larger target is detected. The other channel contains a narrow band-pass filter 8 followed by a frequency to voltage convertor 11 and a threshold detector 12 the output of which is connected to another output terminal 13. The settings of filter 8 and threshold detector in the second channel are such that targets constituted by discontinuities in the ground (such as tip edges) are detected. Both output terminals are connected to the vehicle braking system. <IMAGE>
Description
SPECIFICATION
Improvements in or relating to presence detection
This invention relates to presence detection systems and more specifically to a vehicle-borne detection system.
The invention is particularly applicable to presence detection systems for land vehicles in which an indication is provided or a control signal is generated whereby the braking system of the vehicle is operated if sensing means carried by the vehicle detects an obstruction to the rear whilst the vehicle is being backed. One example of vehicle referred to above is a giant earth moving vehicle such as finds use in the construction of motorways. The operator of such a vehicle has a poor view of the ground to the rear when backing the vehicle, as he is required to do from time to time. For example it is commonly necessary for the vehicle to back to the edge of a tip into which the load carried by the vehicle is to be tipped or dumped. An obstruction of the size of a human being, and even larger obstructions such as smaller vehicles, can easily be missed.It has therefore been recognised as desirable to provide some means for indicating the presence of such targets behind the vehicle and even automatically applying the brakes of the vehicle upon the detection of such a target.
However, systems as previously proposed have suffered from various defects. For example, one previously proposed system employing a continuous wave (CW) radar transmitter and receiver, generally similar to that commonly employed for intruder detection in security systems, suffers from the defect that false returns are commonly received from larger targets at a range greater than that of concern.
Apart from obstructions behind the vehicle there also exists the problem of the driver stopping the vehicle before it reaches a discontinuity in the ground such as the edge of a tip. So far as is known, systems as previously proposed do not address themselves to this last mentioned problem.
The present invention seeks to provide an im
proved vehicle borne presence detection system in which one or more of the above defects are mitigated.
According to this invention a vehicle borne present detection system comprises a frequency modulated continuous wave transmitter, means for directing the output of said transmitter in a direction of travel of said vehicle, a frequency selective receiver provided to receive resulting reflections from targets and responsive to reflections whose frequencies indicate targets within a desired range in said direction of travel and means responsive to the output of said frequency selective receiver for providing a signal when the presence of a target of a certain character is detected.
Action, such as the application of the brakes of the vehicle, may be taken by an operator of the vehicle in
response to said signal but preferably said signal is a control signal and means are provided for initiating
automatic braking of said vehicle upon the generation of said signal.
The output of said frequency selective receiver may be connected via a frequency-to-voltage convertor and a threshold detector to an output terminal connected in operation to apply the brakes of the vehicle whereby said system is responsive to targets generally of the size of a human being or larger.
The output of said frequency selective receiver may be connected via a narrow bandpass filter, a frequency-to-voltage converter and a threshold detector to a signal output terminal whereby said system is responsive to a discontinuity in the ground in the direction of travel of said vehicle at a range, within the overall desired range determined by said frequency selective receiver, as determined by the pass-band of said narrow band pass filter.
Preferably the output of said frequency selective receiver is connected to two channels one of which contains said frequency-to-voltage converter and said threshold detector as first mentioned and the other of which contains said narrow band-bass filter, said frequency-to-voltage convertor and said threshold detector as last mentioned.
As an alternative, two separate transmitter/receiver combinations may be employed, one dedicated to the first mentioned detection of targets of the general size of a human being and one dedicated to the detection of discontinuities in the ground.
Preferably means are provided for mixing received reflections with the frequency modulated continuous wave from said transmitter to produce a difference signal which is applied as input to said frequency selective receiver.
Preferably said frequency modulated continuous wave radar transmitter is one operative at J-band.
Preferably in addition to said output terminal or output terminals being connected to initiate braking upon the detection of a target as aforesaid, said output terminal or output terminals are also connected at the same time to operate an aural or visual alarm.
A common antenna or separate antenna may be provided for transmission and reception.
Preferably said or each antenna is provided as an integral part of a box, for example a cast box, which box also acts as a housing for microwave and processing components of said system and the interconnecting circuitry therefor. Normally, where separate antennae are used for transmission and reception, each is integral with a common box.
Preferably the or each antenna and the box of which it forms an integral part, are of aluminium.
Preferably microwave components of said systems are mounted on the inner end of the or each antenna and said interconnecting circuitry is provided upon a printed circuit board.
Normally said direction of travel will be the rear of said vehicle.
The invention is illustrated in and further described with reference to the accompanying drawing which is a block schematic diagram of one embodiment of a vehicle-borne presence detection system in accordance with the present invention.
Referring to the drawing, the system comprises a radar horn antenna 1 connected via a circulator 2 to the output of a J-band microwave oscillator 3 and via a mixer 4, to the input of a J-band frequency selective receiver 5 so that, in this example, the one antenna acts both as a transmitting antenna and as a receiving antenna.
Connected to frequency modulate the continuous wave produced by microwave oscillator 3 is a modulation generator 6. The arrangement of modulation generator 6 and microwave oscillator 3 is such that applied to the circulator 2 is a frequency modulated continuous wave exhibiting a regular frequency deviation.
Reflected signals received at antenna 1 are routed via circulator 2 to mixer 4 where they are mixed with a sample of the transmitted frequency modulated continuous wave derived from microwave oscillator 3 to produce a difference frequency which is applied to selective receiverS. This difference frequency is proportional to the time delay between the antenna 1 and the target giving rise to the reflections and hence proportional-to the distance of that target from the antenna 1.
Antenna 1 is mounted on the rear of a giant earth moving vehicle. The frequency band of frequency selective receiver 5 is chosen in accordance with the desired range to the rear of the vehicle within which it is desired to detect targets.
Thus responses received from targets within, say, 20' of the antenna 1 will result in a response at the output of selective receiver 5 whereas reflections from targets at greater range will not.
The output of frequency selective receiver 5 is applied both to the input to a frequency-to-voltage convertor7 in one channel and to the input of a narrow bandpass filter 8 in a second channel. The output of frequency-to-voltage convertor 7 is applied via a threshold detector 9 to an output terminal 10.
The setting of threshold detector 9 is chosen so that targets which are generally of the size of a human being or larger cause a control signal to be applied to terminal 10.
The output of narrow pass band filter 8 in the second channel is connected to the input of a frequency-to-voltage convertor 11 the output of which is applied via a threshold detector 12 to an output terminal 13. The band-pass of narrow bandpass filter 8 and the setting of threshold detector 12 are so chosen that an output signal is applied to output terminal 13 when the reflections received by antenna 1 undergo a change due to a discontinuity in the ground behind the vehicle at a particular range, within the overall range set by the pass-band of frequency selective receiverS, as determined by the pass-band of filter 8. This discontinuity in practice may be the edge of a tip over which the load of the vehicle is to be tipped. Terminals 10 and 13 are connected to means (not shown) for actuating an aural orvisual alarm and means (not shown) for controlling the operation of the brakes of the vehicle.
Whilst not illustrated, antenna 1 is formed as an integral part of a cast aluminium box which box also acts as a housing for the microwave and processing components and circuitry described above with reference to and illustrated in Figure 1. The microwave components are bolted to the inner end of the antenna whilst the interconnecting circuitry is provided upon a printed circuit board also mounted with the box.
Claims (5)
1. Avehicle-borne presence detection system comprising a frequency modulated continuous wave transmitter, means for directing the output of said transmitter in a direction of travel of said vehicle, a frequency selective receiver provided to receive resulting reflections from targets and responsive to reflections whose frequencies indicate targets within a desired range in said direction of travel and means responsive to the output of said frequency selective receiver for providing a signal when the presence of a target of a certain character is detected.
2. A system as claimed in claim 1 and wherein said signal is a control signal and means are provided for initiating automatic braking of said vehicle upon the generation of said signal.
3. A system as claimed in claim 1 or 2 and wherein the output of said frequency selective receiver is connected via a frequency-to-voltage convertor and a threshold detectorto an output terminal connected in operation to apply the brakes of the vehicle whereby said system is responsive to targets generally of the size of a human being or larger.
4. A system as claimed in any of the above claims and wherein the output of said frequency selective receiver is connected via a narrow bandpass filter, a frequency-to-voltage convertor and a threshold detector to a signal output terminal, whereby said system is responsive to a discontinuity in the ground in said direction of travel of said vehicle at a range, within the overall desired range determined by said frequency selective receiver, as determined by the pass-band of said narrow bandpass filter.
5. Apparatus according to claim 1 and substantially as described with reference to the accompanying drawing and substantially as illustrated therein.
5. A system as claimed in any of the above claims and wherein means are provided for mixing received reflections with the frequency modulated continuous wave from said transmitter to produce a difference signal which is applied as input to said frequency selective receiver.
6. A system as claimed in any of the above claims and wherein said frequency modulated continuous wave radar transmitter is one operative at
J-band.
7. A system as claimed in any of the above claims and wherein in addition to said output terminal or output terminals being connected to initiate braking upon the detection of a target as aforesaid, said output terminal or output terminals are also connected at the same time to operate an aural or visual alarm.
8. A system as claimed in any of the above claims and wherein a common antenna is provided for transmission and reception.
9. A system as claimed in any of the above claims 1 to 7 and wherein separate antennae are provided for transmission and reception.
10. A system as claimed in claim 8 or 9 and wherein said or each antenna is provided as an integral part of a box, which box also acts as a housing for microwave and processing components of said system and the interconnecting circuitry therefor.
11. A system as claimed in claim 10 as dependent upon claim 9 and wherein each antenna is integral with a common box.
12. A system as claimed in claim 10 or 11 and wherein the or each antenna and the box of which it forms an integral part, are cast aluminium.
13. A system as claimed in any of claims 10 to 12 and wherein the or each antenna and the box of which it forms an integral part are of aluminium.
14. A system as claimed in any of claims 10 to 13 and wherein microwave components of said system are mounted on the inner end of said antenna and said interconnecting circuitry is provided upon a printed circuit board.
15. A system as claimed in any of the above claims and wherein said direction of travel is to the rear of said vehicle.
16. Avehicle-borne presence detection system substantially as herein described with reference to the accompanying drawing.
17. Avehicle-borne braking control system incorporating a detection system as claimed in any of the above claims.
New claims or amendments to claims filed on 18 Jun 1984.
Superseded claims All.
New or amended claims:
1. Apparatus for detecting the continuity for discontinuity of groun over which a vehicle is travelling comprising a transmitter for transmitting a signal in the direction of travel, a receiver for receiving signals derived from reflections of the transmitted signal from the ground, and a threshold detector connected to receive an output of the receiver and to produce an output indicative of the continuity or discontinuity of the ground.
2. Apparatus according to claim 1 in which the transmitter is designed to transmit a frequency modulated continuous wave signal and the receiver includes means for mixing the transmitted and received signals and a filter for passing to the threshold detector an output from the mixer within a particular frequency window and therefore indicative of a signal received from the ground at a particular range of distance from the vehicle.
3. Apparatus according to claim 1 or 2 in which the output of the threshold detector is connected to control means for braking the vehicle when a discontinuity is detected.
4. Apparatus according to claim 1,2 or 3 including means for generating an audible or visual alarm in response to an output of the threshold detector indicative of a discontinuity.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| GB08307656A GB2139035B (en) | 1983-03-18 | 1983-03-18 | Radar vehicle braking control |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| GB08307656A GB2139035B (en) | 1983-03-18 | 1983-03-18 | Radar vehicle braking control |
Publications (3)
| Publication Number | Publication Date |
|---|---|
| GB8307656D0 GB8307656D0 (en) | 1983-04-27 |
| GB2139035A true GB2139035A (en) | 1984-10-31 |
| GB2139035B GB2139035B (en) | 1987-06-03 |
Family
ID=10539883
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| GB08307656A Expired GB2139035B (en) | 1983-03-18 | 1983-03-18 | Radar vehicle braking control |
Country Status (1)
| Country | Link |
|---|---|
| GB (1) | GB2139035B (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US7492306B2 (en) * | 2006-03-24 | 2009-02-17 | Tdk Corporation | Boundary crossing object detection system |
Citations (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB887622A (en) * | 1959-05-12 | 1962-01-24 | Nat Res Dev | A frequency-modulation echo-sounder |
| GB892986A (en) * | 1959-03-30 | 1962-04-04 | Bendix Corp | Selective range detecting system |
| GB1308102A (en) * | 1970-06-02 | 1973-02-21 | Bendix Corp | Range-detecting doppler radar |
| GB1404634A (en) * | 1971-11-26 | 1975-09-03 | Messerschmitt Boelkow Blohm | Apparatus for measuring and indicating distance between a motor vehicle carrying the apparatus and an obstacle |
| GB1420917A (en) * | 1971-12-18 | 1976-01-14 | Lucas Industries Ltd | Headway control systems for road vehicles |
| GB1495387A (en) * | 1973-12-22 | 1977-12-14 | Lucas Ltd Joseph | Road vehicle radar system |
| GB1509138A (en) * | 1975-04-04 | 1978-04-26 | Int Standard Electric Corp | Anti-collision radar |
| GB2040639A (en) * | 1979-01-11 | 1980-08-28 | Int Standard Electric Corp | Collision avoidance radar |
| GB2047405A (en) * | 1979-03-29 | 1980-11-26 | Craven G C | Proximity warning devices for vehicles |
| GB2055745A (en) * | 1979-08-15 | 1981-03-11 | Illinois Tool Works | Vessels with pouring spouts |
-
1983
- 1983-03-18 GB GB08307656A patent/GB2139035B/en not_active Expired
Patent Citations (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB892986A (en) * | 1959-03-30 | 1962-04-04 | Bendix Corp | Selective range detecting system |
| GB887622A (en) * | 1959-05-12 | 1962-01-24 | Nat Res Dev | A frequency-modulation echo-sounder |
| GB1308102A (en) * | 1970-06-02 | 1973-02-21 | Bendix Corp | Range-detecting doppler radar |
| GB1404634A (en) * | 1971-11-26 | 1975-09-03 | Messerschmitt Boelkow Blohm | Apparatus for measuring and indicating distance between a motor vehicle carrying the apparatus and an obstacle |
| GB1420917A (en) * | 1971-12-18 | 1976-01-14 | Lucas Industries Ltd | Headway control systems for road vehicles |
| GB1495387A (en) * | 1973-12-22 | 1977-12-14 | Lucas Ltd Joseph | Road vehicle radar system |
| GB1509138A (en) * | 1975-04-04 | 1978-04-26 | Int Standard Electric Corp | Anti-collision radar |
| GB2040639A (en) * | 1979-01-11 | 1980-08-28 | Int Standard Electric Corp | Collision avoidance radar |
| GB2047405A (en) * | 1979-03-29 | 1980-11-26 | Craven G C | Proximity warning devices for vehicles |
| GB2055745A (en) * | 1979-08-15 | 1981-03-11 | Illinois Tool Works | Vessels with pouring spouts |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US7492306B2 (en) * | 2006-03-24 | 2009-02-17 | Tdk Corporation | Boundary crossing object detection system |
Also Published As
| Publication number | Publication date |
|---|---|
| GB8307656D0 (en) | 1983-04-27 |
| GB2139035B (en) | 1987-06-03 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| 732 | Registration of transactions, instruments or events in the register (sect. 32/1977) | ||
| PCNP | Patent ceased through non-payment of renewal fee |