Therefore, a fundamental purpose of the present invention provides the system and method that overcomes the above problems.In this respect, a special purpose of the present invention provides and can carry out that accurate position is determined and the docking guidance system of authentication to the aircraft in the airport.Other purpose of the present invention is by adopting this system and the communication between people's computing machine one by one, information is provided and is used to monitor other method that group method is operated for the docking of aircraft in the control airport and the individuality of parking and colony by display unit.
Further purpose provides the accurately security of docking control of numeral, and the realization docking control in extremely worthwhile mode is provided.
Further purpose is to provide aircraft docking information to show that it comprises about the range information from a suitable halt to degree of closeness the aircraft to the driver who makes the aircraft docking, copilot and other staff.Another free-revving engine provides location and the direction of closing of relatively also determining aircraft automatically not to be departed from by the necessary suitable runway of the particular type aircraft of docking, particularly, with the mode that counts down on display, monitor apart from aircraft near distance, the deviation position of the suitable center line that comprise the distance that is used for docking, is used for docking and the check result of type of airplane.
Another other purpose provides not only to driver or copilot provide azimuth guidance, but also provides hardstand scanning so that aircraft is appropriate and the system of docking safely.Other purpose provides the special sensitive system of the accurate stop position that can realize minimum deflection.
Further purpose provides extremely flexibly, and allows to carry out system such as the new operating parameter of the identification corresponding to the aircraft in the airport, navigation and the docking that increase new type of airplane, standby and auxiliary stop position and other relevant information.
These and other objects of the present invention realize to survey the system and method that whether object exists in the airport by the light pulse that employing such as laser pulse is provided, for example, utilize from being arranged in the light pulse of reflecting from object that the airport capture region is launched such as the light pulse of laser pulse near the mirror on the object direction and collected that the expression object exists.Similarly, this technology can be determined the aircraft position in the capture region and survey thus.
The present invention also is provided for verifying the system and method for detected target thing identity, for example, can determine to be the right type aircraft near docking device and docking there.For the shape of determining to detect whether corresponding with known form, this recognition system and method be at an angle to the light pulse of object emission such as laser pulse, and collect the pulse that reflects from object in a sniffer that the profile of pulse with corresponding known target thing shape that be reflected can be compared.
In addition, the invention provides the system and method for tracking near object, wherein in order to determine that this object is with respect to the position of an imaginary axis that predetermined docking point sent with in order to survey from this object to the distance this predetermined point to reach the purpose of determining this object position, to be transmitted into this such as the light pulse of laser pulse, and collect and adopt the light that reflects from this object near on the object.
Therefore, the invention provides in the capture region of a setting or control area one near the location of aircraft or catch and to the identification or the mensuration of its shape, this is essential to starting an aircraft docking process.After this, corresponding with the present invention, a display that can make this aircraft docking of having discerned in suitable docking zone of carrying out passenger, goods or similarly unloading is provided.
The present invention has realized these functions, has eliminated sensor before this and must be placed on code requirement on the hardstand, docking zone.Its result has not only obviously reduced set-up time and supplementary costs, but also has reduced maintenance cost after this.In addition, the present invention allows to be modified as present system from existed system, the hardstand structure is had certain requirement and the docking zone of using is caused interference necessary and needn't resemble former docking system.
Among the preferential embodiment according to system of the present invention, the driver that Xiang Yiwei guides an airplane to enter a gate in the airport provides a real-time display device, for example, this display is suspended on top, this gate, indicates this aircraft must begin to make the position of the point of this aircraft brake with respect to this driver.The lateral attitude that also shows the preset lines that this aircraft is deferred to respect to this type aircraft is so that aircraft promptly arrives this gate.
In the software of system of the present invention, preferentially comprise four modules of the main calculation task and the control hardware that are used to carry out this system.In these modules, one is used for catching, and one is used for identification, and one is used to follow the tracks of and a calibration that is used for system.
In a preferential embodiment of the present invention, capture module control is used to launch the equipment of light pulse with scanning docking gate forefoot area.Therefore, when using the pulse of specularly reflected and emission such as laser pulse, this capture module guides this zone of this laser beam flying to detect an object until it constantly and enters this zone.In case it detects an object, this capture module calculates the distance and the angle position of this object, and control is carried out the transition to tracking module.
In case started, this tracking module follow this near aircraft to the gate, provide simultaneously with respect to the relevant aircraft lateral attitude of desired halt and the information of distance.Adopt this information, the driver can correct the aircraft trace and at accurate location brake, the result will make aircraft stop at the desired docking position of aiming at the gate.During this was followed the tracks of, an identification module at first scanned this detected target thing to determine whether its profile mates with the reference contours of expected type of airplane.If profile does not match, the notifications airport tower also sends a signal to stop the docking operation.
At last, calibration module is adjusted the distance and measurement of angle is calibrated, and is accurately corresponding with the distance and the angle of this aircraft to guarantee such as the reading of the sniffer of laser range finder (Laser Range Finder).This module is moved to determine the continuous precision of system in seizure and tracking module period ground.
Characteristics of the present invention and advantage will become obvious in company with the following detailed description of accompanying drawing.Wherein:
Table I is the plane reference contours form of a preferential embodiment that is used for setting up in system of the present invention the identity of an aircraft;
Table II be one in order in system of the present invention, effectively and economically to make the comparison form of a preferential embodiment of an aircraft docking.
Now Fig. 1-10 and Table I-II are done reference number, wherein identical label is represented components identical among each figure.Detailed description below, shown in generally represented by the stage of label in the process flow diagram by the element numerals in this label back bracket.
For Fig. 1, be the function of the tracking of the checking of 10 system of the present invention compute location, object identity and object by unified label in the drawings with object, object preferentially is set at aircraft 12.In operation, in case 12 landing of scheduling control tower 14 commander one airplane, its reporting system one airplane is near the type of gate 16 and the aircraft expected (promptly 747, L-1011 etc.).System 10 scanning gates 16 region in front position the object that is identified as aircraft 12 until it then.System 10 compares the profile of aircraft 12 and the reference contours of desired type airplane then.If the aircraft of location and desired aircraft are not inconsistent, system gives notice or signal and stop docking to tower 14.
If object is desired aircraft 12, by being that the driver shows remaining to the distance of appropriate halt 29 and the lateral attitude 31 of aircraft 12 in real time, system 10 imports gate 16 with it.The lateral attitude 31 that aircraft 12 is provided on display 18 is to allow the driver from the position of correct angularity correction near this aircraft at gate 16.In case aircraft 12 is in halt 53, then on display 18, show this situation, and the driver stops aircraft.Adopt system 10 of the present invention,, needn't adjust gate 16 by the surface work personnel and can make aircraft aim at gate 16 exactly in case it should be noted that aircraft 12 stops to move.
With reference to Fig. 2, system 10 comprises 24,25 and microprocessors 26 of 18, two stepper motors of 21,22, one display units of 20, two mirrors of a laser range finder (LRF).Suitable LRF product used herein is sold by Laser Atlanta Corporation, can launch laser pulse and be received in those pulses that reflect on the distant object thing and the distance of calculating these objects.
The arrangement of system 10 is to have one to connect 28 between the serial ports of LRF 20 and microprocessor 26.Adopt this connection, this LRF 20 approximately sent measurement data to microprocessor 26 in per 1/400 second.The quilt unification of system 10 is set at 23 hardware element by microprocessor 26 controls of having programmed.In addition, microprocessor 26 is carried data to display 18.As driver's man-machine interface, display unit 18 is placed on the top at gate 16, to show that to the driver aircraft is apart from the distance of halt 29, confirmed as the type of approaching aircraft 30 and the lateral attitude 31 of aircraft by system 10.Adopt this display, the driver can adjust aircraft 12 near gate 16, is on the correct angle near the gate to guarantee aircraft.If display 18 shows wrong type of airplane 30, the driver can end approaching before accident occurring.Since this system attempt as 737 handle one bigger by 747, it may cause large-scale accident, this pair of verification guaranteed the security of passenger, aircraft and airport installation.
Except display 18, the data that microprocessor 26 is handled from LRF 20, and by its direction that is connected 32 control laser beam 20 with stepper motor 24,25.Stepper motor 24,25 is connected to mirror 21,22, and moves according to the instruction of microprocessor 26.Therefore, by control step motor 24,25, microprocessor 26 can change the angle of mirror 21,22, and aiming is from the laser pulse of LRF 20.
Mirror 21,22 comes the aiming laser bundle by outside reflector laser pulse on the tarmac of airport.In this preferential embodiment, LRF 20 does not move.Laser scanning is finished by mirror.The level angle of mirror 22 control laser beam, another mirror 21 control vertical angles simultaneously.By starting stepper motor 24,25, microprocessor 26 is controlled the angle of mirrors, and therefore controls the direction of laser pulse.
System 10 adopts the horizontal mirror 20 of EscapEDM-453 type step motor control, be implemented in ± continues horizontal scanning with the angle step of about 0.1 degree of being equivalent to per step 16 micro-steppings in 10 degree.Carry out an angle stepping to replying, i.e. about 2.5ms from each that read the unit.The vertical mirror 21 of may command be implemented in-20 and-30 the degree between with a stepping of the every 2.5ms of correspondence about 0.1 the degree angle step carry out vertical scanning.When the head height is determined and when aircraft 12 is identified, adopts vertical mirror 21 to carry out vertical scanning.During tracing mode, continue to adjust vertical mirror 21 so that horizontal scanning tracking aircraft 12 head points all the time.
With reference to Fig. 3, system 10 is divided into three parts with the place of its front according to distance.Part farthest beyond about 50 meters is a capture region 50.In this zone 50, system 10 surveys the head of this aircraft and the horizontal and vertical position of guestimate aircraft 12.Capture region 50 with interior be identified region 51.In this zone, system 10 is according to the profile of the profile checking aircraft 12 that has stored.This system 10 is presented at aircraft 12 in this zone with respect to the lateral attitude of a preset lines on display 18, last, what approach LRF 20 most is to show or tracing area 52.In this viewing area 52, system 10 shows the horizontal and vertical position of aircraft 12 with respect to accurate stop position with pinpoint accuracy.52 end is a halt 53 in the viewing area.At halt 53, aircraft will be in the accurate position at gate 16.
Except hardware and software, system 10 also has the database that holds the type of airplane reference contours that may run into corresponding to it.At this lane database, the profile of corresponding every kind of type of airplane has stored in this system, as the level and the vertically profiling of the echo pattern of the desired the sort of type of airplane of reflection.
With reference to table I, system preserves horizontal profile with the form of table I, and the row 40 of table I is with the angle step numbering, and its row 41 are numbered with the distance of the stop position of the sort of type airplane of distance.Except numbered row, also comprise the row 42 of the vertical angle of each distance plane nose that is provided at LRF, a row 44 and the sequence number row 44 that corresponding each contoured profile distance value is provided that the form coefficient k of corresponding profile is provided in the form.Main body 43 in the table I be included in desired under various scanning angles corresponding to the distance of the sort of type of airplane with to the distance of halt 53.
Theoretically, corresponding 50 angle step and need to comprise 50 * 50 in the table I, or 2500 items to 50 distances of halt 53.Yet because profile numerical value does not require the value of feedback on all angles of corresponding all distances, the item that table I comprises in fact will be far fewer than this number.In fact typical form requires to comprise 500 to 1000 data.Known programming technique provides the memory space that uses the method for the complete form of part and do not adopt complete form to need.
Except this horizontal profile, system 10 also preserves the vertically profiling of every kind of type of airplane.Except it row with the angle step on vertical direction numbering with and column number in comprise to the distance of stop position than horizontal profile still less, the storage mode of this profile is identical with horizontal profile.Because it just is used for discerning aircraft 12 and determining its head height in the limited range of the distance of LRF 20 at identified region 51, so vertically profiling needs less row.Therefore, vertically profiling only is stored in desired echo in this scope and does not waste the data-storing space on unwanted data.
System 10 adopts hardware described above and database that aircraft is positioned, discerns and follows the tracks of, and its step is as follows:
With reference to Fig. 4, the software that moves in this microprocessor is carried out a master routine of the subroutine that comprises calibration mode 60, trap mode 62 and docking pattern 64.This microprocessor is at first carried out calibration mode 60, is trap mode 62 then, is docking pattern 64 at last.In case aircraft 12 dockings, EOP (end of program).These patterns are described in further detail below:
Calibration mode
For guaranteeing the precision of system, step corresponding shown in Figure 5 before aircraft 12 is captured and in each interim of following the tracks of, is programmed so that it carries out self calibration to microprocessor 26.The calibration of system 10 has guaranteed that the pass between stepper motor 24,25 and the sighted direction is known.The linear measure longimetry performance of LRF 20 is also tested.
With reference to Fig. 6, in order to calibrate, system 10 adopts the side dull and stereotyped 66 on the known location.Flat board 66 has 6 meters position to install at distance LRF 20, and height is identical with LRF 20.
In order to calibrate, system will (α β) be set at (0,0) emission with guided laser Shu Xiangqian.So place vertical mirror 22 then so that laser beam guides to again rear portion or the additional mirror 68 (100) of lead beam to calibration dull and stereotyped 66 backward.Microprocessor 26 adopts stepper motor 24,25 to come mobile mirror 21,22 to find the center of calibration dull and stereotyped 66 until it then.In case it finds the center of calibration dull and stereotyped 66, microprocessor 26 storage angle (α in that
Cp, β
Cp) and they and the expected angle that stored compared (102).System 10 also with write down apart from distance and the expectation numeric ratio that has stored at dull and stereotyped 66 centers of calibration (102).If the numerical value that is write down and the numerical value of storage are not inconsistent, microprocessor 26 changes the calibration constants of determining desired numerical value, until they conform to (104,106).Yet, if these numerical value when installing to store the numerical value deviation too big, send an alarm (108).
Trap mode
Beginning, airport tower 14 reporting systems 10 are waited for the type of an approaching aircraft 12 and institute's expectation aircraft.This signal drive software as illustrated in fig. 8 proceeds to trap mode 62.At trap mode 62, microprocessor 26 adopts stepper motor 24,25 to come guided laser horizontal scanning capture region 50 to seek aircraft 12.This horizontal scanning is carried out with the vertical angle corresponding to the head height of desired type airplane at the central point of capture region 50.
In order to determine the accurate height of scanning, the vertical angle of microprocessor 26 calculating laser pulses is as follows:
β
f=arctan[(H-h)/l
f]
H=LRF 20 height overhead in the formula, the head height of the desired aircraft of h=, l
f=the distance at 50 center from LRF20 to the capture region.A desired aircraft 12 of correspondence can be obtained by this formula and the vertical angle of search can be made in the center of capture region 50 with the correct mirror 21 that highly carries out.On the other hand, the β for the dissimilar aircrafts that are in a certain distance can store in system 10 in database
fNumerical value.Yet, because it can only catch aircraft 12 in the single distance of distance LRF 20, so the β that is stored
fLimited the dirigibility of system 10.
In capture region 50 and by adopting this vertical angle, microprocessor 26 guided laser bundles are with about 0.1 degree pulsating water simple scan at interval.This microprocessor 26 is by changing angle [alpha], one with a level angle that center line became from LRF 20 beginnings, the numerical value ± α of qualification when beginning to install
MaxBetween carry out horizontal scanning.Typically, α
MaxBe set at 50, promptly adopt 0.1 degree pulse, be equivalent to 5 degree and cause the scanning of 10 degree scopes.
In capture region 50, the emission of laser pulse causes from the echo of object or reflection.The sniffer of LRF 20 is caught reflected impulse, to receiving Time Calculation the echo to the distance of object, and sends the distance values that corresponding each echo are calculated to microprocessor 26 from transponder pulse.Total echo or collision (hits) number (70) in per 1 degree section in microprocessor 26 each register in a data storing apparatus in the storage capture region 50.Because pulse produces at interval with 0.1 degree, can produce 10 echoes of as many as at each section.Microprocessor 26 storage variable s
αThese collisions of name, wherein α from 1 to 10 changes, the situation of per 1 degree part of the capture region 50 of reflection 10 degree.
Except storing each regional Collision Number, this microprocessor 26 also stores the distance from LRF 20 to this object of corresponding each collision or echo in a data storing apparatus.The enough big storage medium of distance needs that stores each reflection is so that 10 of storage as many as collide or 100 possibilities of as many as numerical value in per 1 degree of capture region 50.Under many circumstances, because the great majority input is empty, known programming technique can require storage capability to reduce, and distributes to the required register number of these numerical value and is lower than 100.
In case obtain these data from single pass, microprocessor 26 is by statistics and s
αCalculate the total s of echo in the scanning
TThen, microprocessor 26 calculates the maximum summation s of the echo of 3 adjacent sections
M(72).In other words, s
MBe (s
α-1, s
α, s
α+1) maximum summation.
In case calculate s
MAnd s
T, microprocessor 26 determines that whether echo is from approaching aircraft 12.If s
MBe not more than 24, then show and do not find aircraft 12, and microprocessor 26 turns back to the place that begins of capture module 62.If the maximum summation s of echo
MGreater than 24 (74), represent that then the aircraft 12 of " possibility " has been positioned.If the aircraft 12 of " possibility " has been positioned, this micro-processor verification s then
M/ s
TWhether greater than 0.5 (76), half of all number of echoes whether 3 adjacent areas that perhaps have maximum summation are included in the scanning to be received at least.
If s
M/ s
TGreater than 0.5, microprocessor 26 calculates the position (78,82) at echo center.The angle position at echo center is calculated as follows:
α
t=α
v+(S
α+1-S
α-1)/(S
α-1+S
α+S
α+1)
S wherein
αProvide s
MS
α, α
vBe corresponding to this s
αThe angle section.
The lengthwise position at echo center is calculated as follows:
l
t=(1/n)
i=1∑
10l
avi
L wherein
AviBe to work as pulse from sectors
vThe measurement numerical value of an echo that returns, or apart from the distance of object; N is in the sum of this regional measurement data (78,82).Because the maximum possible sum of measurement data is 10, n must be less than or equal to 10.
Yet, if s
M/ s
T<0.5, then may cause echo by snow or other aircraft in short range.If caused by the aircraft in the short range, that aircraft may be positioned in the decentering line very near the place, therefore supposes α
vShould be 0 rather than the numerical value that calculates of front, and l
tShould be the mean distance (80) that draws by 3 intermediate sectors.If range distribution is too big, microprocessor 26 does not find an aircraft 12, then turn back to trap mode 62 begin the place (81).
After having calculated the position of aircraft 12, system 10 switches to docking pattern 64.
The docking pattern
Docking pattern 64 shown in Figure 4 comprises three phases, tracking phase 84, height measuring phases 86 and cognitive phase 88.At tracking phase 84, system 10 monitoring provides about the axial location 31 of aircraft with apart from the information of the distance of halt 53 to the driver near the position of aircraft 12 and by display 18.System 10 begins tracking aircraft 12 by horizontal scanning.
With reference to Fig. 8, in the scan period first time of tracking phase 84, microprocessor 26 is controlled LRF 20 with single angle step α, or preferentially spends at interval at (α with 0.1
t-α
p-10) and (α
t+ α
p+ 10) send out laser pulse between, wherein α
tBe the angle position that during trap mode 62, is defined as the echo center, α
pBe in the maximum angle position in the front profile row that comprises distance values.
For the first time after the scanning, α with a step-length of each LRF numerical value that receives at (α
s-α
p-10) and (α
s+ α
p+ 10) between backward or stepping forward.α wherein
sIt is the orientation angles position of determining in the scanning in front.
At tracking phase 84, vertical angle β be set to corresponding from the reference contours table I, obtain be identified aircraft 12 at present apart from the required magnitude of the distance of LRF 20.Deserve the front profile row refer to represent a position less than but approach l
tRow.
Microprocessor 26 adopts the vertical angle of seeking corresponding aircraft current distance apart from the distance of halt 53 from the profile table I.In the scan period first time, calculated distance l during trap mode 62
tDetermine the suitable row in the profile table I and determine the angle of aircraft 12 thus.For each follow-up scanning, microprocessor 26 adopts the β (112) of reflection in the row of the profile table I of the current distance of halt 53.
Employing is from the data that scan and horizontal profile table I obtains, and microprocessor 26 is set up relatively form II.With reference to form II, relatively form II is a two-dimentional form, is 91 with umber of pulse or angle number of steps label, and line label is i.Adopt this label, the form that corresponding each row is listed as in can form is looked into rope to following information: l
i92, the measuring distance under this angle step apart from object; l
Ki93, the measurement data compensation of the skew that caused by skew (is equaled l
iDeduct the total drift numerical value s of scan period in the end
m, deduct numerical value i and be multiplied by the mean deviation s during each stepping in the scanning in the end
p, i.e. (l
i-(s
m-i
Sp)); d
i94, the profile of generation and the distance between the reference contours (equal at the profile numerical value r of profile apart from j place respective angles
IiDeduct l
Ki); a
i95, (the reference contours numerical value r that equals at 0 degree place of the distance between plane nose and the surveying instrument
J50Deduct d
i); a
c96, (head when equaling the end of scan in the end is apart from a for the head estimated after each stepping distance
m, deduct numerical value i and be multiplied by s
p); a
d, the deviation of the head distance of estimating and measuring (equals a
iDeduct a
eAbsolute value); Symbol 97 (Note 97) with the echo that causes by an aircraft of expressing possibility.
In the scan period first time of tracking phase 84, system 10 adopt show less than but approach numerical value 1
tThe horizontal profile row of an aircraft position i.For each new scanning, select its numerical value less than but approach (a
m-s
m) profile row, a wherein
mBe last measuring distance for aircraft 12, s
mIt is the skew of the aircraft of scan period in the end.In addition, with the numerical value lateral excursion α of profile
sWith the lateral attitude (112) that compensates this aircraft.
In each scan period, microprocessor 26 also produces a range distribution form (DDT).This form comprises the numerical value a when appearing at comparison form II
iDistribution.Therefore, in DDT has between 10 to 100 meters of the expressions at each a in form II relatively under 1 meter increment
iThe item of numerical value occurrence number.
After each scanning, system 10 adopts DDT to calculate the mean distance a of correct halt 53
mData among the microprocessor 26 scanning DDT are to seek two adjacencies of its value summation maximum in DDT.Then, microprocessor 26 in form II relatively to comprise corresponding to have maximum and two DDT capable in the item a of arbitrary row
iEach row, in symbol 97 row, carry out mark (114).
Then, system 10 determines lateral deviation and skew (116).Microprocessor 26 is at first set:
2d=α
max-α
min
α wherein
MaxAnd α
MinBe d among the comparison form II
iMinimum and maximum α numerical value in the numerical value continuous mark piece.In addition, microprocessor 26 with
Y
1=∑d
i
Sign d in the computing block
iThe first half, and with
Y2=∑d
i
The latter half in the computing block.Adopt Y
1And Y
2, " a " 116 is calculated as follows:
a=kx(Y
1-Y
2)/d
2
Wherein k is provided by reference contours.Preferentially be set at 1 set-point if " a " surpasses one, then hypothesis has a lateral deviation that approximates " a " greatly.Make the l among the comparison form II then
iRow displacement " a " individual step-length, and recomputate comparison form II.This process lasts till that always " a " is preferably 1 the numerical value of rule of thumb setting up less than one.l
iThe total drift α of row
sBe considered to equal lateral deviation or skew (116).If it is big that lateral excursion preferentially is set at 1 predetermined value than one, horizontal adjustment profile (118,120) before scanning next time then.
After the lateral excursion verification, microprocessor 26 provides the total horizontal adjustment amount (122) corresponding to the profile of the lateral attitude 31 of aircraft 12 on display 18.
Next, microprocessor 26 calculates the head of this aircraft apart from a
m,
a
m=∑(flaggcd?a
i)/N
Wherein N is sign a
iSum.By from deduction to the distance of this head from LRF 20 to halt 53 distance, microprocessor 26 adopts a
mCalculate the distance (124) of aircraft 12 to halt 53.
In case it calculates the distance of halt 53, this microprocessor 26 calculates the mean deviation s of scan period in the end
mThe skew of scan period in the end can be calculated as follows:
S
m=a
m-1-a
m
A wherein
M-1And a
mBelong to last twice scanning.For the scanning first time in tracking phase 84, s
mBe set at 0.
Mean deviation s during each stepping
pCan be calculated as follows:
S
p=S
m/P
Wherein P is total number of steps of corresponding last scan period.
Microprocessor 26 is by showing to come the distance of driver to stop position 53 on display unit 18,29.By be shown to the distance of stop position 29,53 after each scanning, this driver receives the information of relevant aircraft 12 apart from the continuous updating of halt distance in real time.
If aircraft 12 is in viewing area 52, then lateral attitude 31 and lengthwise position 29 all are presented at (126,128) on the display 18.In case microprocessor 26 shows the position of aircraft 12, then this tracking phase finishes.
In case it finishes this tracking phase, whether microprocessor 26 judges greater than 0.5 whether tracking loses (83) by the capable sum of mark in the checking scanning in the end divided by the quantity of overall measurement numerical value or echo.In other words, if do not correspond to this reference contours, then follow the tracks of and lose above 50% echo.If follow the tracks of lose and aircraft 12 apart from the distance of halt greater than 12 meters, then system 10 turns back to trap mode 62 (85).If follow the tracks of and to lose and aircraft 12 is less than or equal to 12 meters apart from the distance of halt 53, then system 10 opens stop signals and follows the tracks of with driver and lose (85,87).
Do not lose if follow the tracks of, then this processor 26 determines whether the head height is determined (130).If be not determined highly as yet, microprocessor 26 enters into height measuring phases 86.If be determined highly, then whether microprocessor 26 checking aircrafts are identified (132).
In this height measuring phases as shown in Figure 9, microprocessor 26 is determined the head height by guiding LRF 20 vertical scanning.System adopts the head height to sweep away the head end to guarantee horizontal scanning.
For the validator head height, this microprocessor 26 is set at a predetermined value β with β
Max, make its reduction with each reception/reflected impulse 0.1 degree step-length at interval then, until reaching another predetermined value β
Minβ
MinAnd β
MaxSet during installation, its representative value is respectively-20 and 30 degree.When β reaches β
MinAfter, this microprocessor upwards guides stepper motor 24,25 to reach β until it
MaxBy α being set at the last time position of orientation α of scanning
s, carry out vertical scanning.
By adopting the plane distance of measuring, this microprocessor 26 is selected near the row (140) in the vertically profiling form of measuring distance.Data that obtain by scanning and the data in the vertically profiling form, this microprocessor 26 is created a relatively form II.For Fig. 4, relatively form II is a two-dimentional form, is 91 with umber of pulse or angle number of steps label, and line label is i.Adopt this label, the form that corresponding each row can be listed as is looked into rope to following information: l
i92, the measuring distance under this angle step apart from object; l
Ki93, compensation (equals l to the measurement data of the skew that caused by skew
iDeduct the total drift numerical value s of scan period in the end
m, deduct numerical value i and be multiplied by the mean deviation s during each stepping in the scanning in the end
p); d
i94, the profile of generation and the distance between the reference contours (equal at the profile numerical value r of profile apart from j place respective angles
IjDeduct l
Ki); a
i95, (the reference contours numerical value r that equals at 0 degree place of the distance between plane nose and the surveying instrument
J50Deduct d
i); a
c96, (head when equaling the end of scan in the end is apart from a for the head estimated after each stepping distance
m, deduct numerical value i and be multiplied by s
p); a
d, the deviation of the head distance of estimating and measuring (equals a
iDeduct a
eAbsolute value); Symbol 97 with the echo that causes by an aircraft 12 of expressing possibility.
In each scan period, microprocessor 26 also produces a range distribution form (DDT).This form comprises as comparing the numerical value a among the form II
iDistribution.Therefore, be each numerical value a in form II relatively of increment with 1 meter in this DDT has between 10 to 100 meters of the expressions
iThe item of occurrence number.
After each scanning, system 10 adopts DDT to calculate the mean distance a of correct halt 53
mData among the microprocessor 26 scanning DDT are to seek two adjacencies of its summation maximum in DDT.Then, microprocessor 26 in form II relatively to comprise corresponding to have maximum and two DDT capable in the item a of arbitrary row
iEach row, in symbol 97 row, carry out mark (142).
In case it is accomplished to the calculating of the mean distance of correct halt 53, microprocessor 26 calculates the mean deviation of scan period in the end.What in the end scan period was offset is calculated as follows:
s
m=a
m-1-a
m
A wherein
M-1And a
mBelong to last twice scanning.For the scanning first time in tracking phase 84, s
mBe set at 0.Mean deviation s for each stepping
pCan be calculated as follows:
s
p=s
m/P
Wherein P is total number of steps of corresponding last scan period.
By with nominal head height, the predetermined altitude when promptly desired aircraft is unloaded adds vertical or height tolerance calculates actual head height.Therefore, in order to determine the head height, system 10 at first determines vertical or height tolerance (144).Vertical missing can be by following set-up and calculated:
2d=β
max-β
min
β wherein
MaxAnd β
MinBe for comparing d among the form II
iThe minimum and maximum β numerical value of the continuous mark piece of numerical value.In addition, microprocessor 26 with
Y
1=∑d
i
Sign d in the computing block
iThe first half, and with
Y
2=∑d
i
The latter half in the computing block.Adopt Y
1And Y
2, " a " is calculated as follows:
a=kx(Y
1-Y
2)/d
2
Wherein k is provided by this reference contours.Preferentially be set at 1 set-point if " a " surpasses one, then hypothesis has a vertical missing that approximates " a " greatly.Then, make l among the comparison form II
iRow displacement " a " individual step-length, and refresh (re-screen) and compare form II and recomputate " a ".This process lasts till that always " a " is preferably 1 given numerical value less than one.L
iThe total displacement β of row
sBe considered to equal height tolerance (144).Adjust the β among the vertical relatively form II then
iValue is β
i+ Δ β
i, height tolerance Δ β wherein
iFor
Δβ
j=β
s?×(a
mβ+a
s)/(a
j+a
s)
A in the formula
M βBe when calculating β
sThe time a
mEffective value.
In case height tolerance determines whether microprocessor 26 verifications it be preferably 1 predetermined value (146) greater than one.If this deviation is greater than that numerical value, then corresponding that deviation, microprocessor 26 vertical these profiles (148) of adjusting.Microprocessor 26 with vertical adjustment amount as with the deviation of nominal head height storage (150).The true altitude of this aircraft is that nominal head height adds this departure.In case it finishes height measuring phases 86, then microprocessor 26 turns back to tracking phase 84.
If microprocessor 26 has been determined the head height, it is skipped height measuring phases 86 and determines whether aircraft 12 is identified (130,132).If aircraft 12 has been identified, then whether microprocessor 26 verification aircrafts 12 have arrived this stop position (134).If arrived this stop position, then these processor 26 demonstrations stop sign, and system 10 finishes docking pattern 64 (136).If aircraft 12 is the no show stop position still, then microprocessor 26 turns back to tracking phase 84 (134).
If aircraft 12 is unrecognized, whether microprocessor 26 verification aircrafts 12 are less than or equal to 12 meters (133) apart from the distance of stop position 53.If aircraft 12 is no more than 12 meters apart from the distance of stop position 53, then system's 10 demonstrations stop sign with driver recognition failures (135).Shown stop the sign after, this system 10 closes.
If greater than 12 meters, then microprocessor 26 enters cognitive phase shown in Figure 10 (133,88) to aircraft 12 apart from the distance of stop position 53.At cognitive phase 88, microprocessor 26 create one relatively form II with the result that reflects other vertical scanning and the content (152,154) in this profile form.Because the scanning of front provides and has been enough to determine height but is not enough to recognition data, other vertical scanning carries out in cognitive phase 88.In fact, before being discerned reliably, need repeatedly to scan.Calculating vertical shift 156, verification it not excessive 158 with corresponding to the skew vertical adjustment profile 160, until skew be reduced to be lower than one be preferably 1 specified rate after, the mean distance (162) that microprocessor 26 calculates between the mean distance between the echo that is labeled and this profile and this echo that is labeled and this mean distance.
After vertical and horizontal scanning, the mean distance d between the measured and correct profile
mAnd be calculated as follows with the deviation T of this mean distance:
d
m=∑d
i/N
T=∑|d
i-d
m|/N
For two profiles, if T all is preferably 5 given numerical value less than one, as long as receive the echo of sufficient amount, then aircraft 12 is judged as being this right type (164).The foundation that whether receives the sufficient amount echo is:
N/sizc>0.75
Wherein N is the quantity of " reception " echo, and " size " is most probable number.If aircraft 12 is not this right type, this microprocessor display stop flag 136 and suspend docking pattern 64 then.In case microprocessor 26 is finished this cognitive phase 88, then turns back to tracking phase 84.
Together with its specific embodiment description of this invention, those technician in this field will understand, can much change under the situation that does not deviate from the thought of the present invention that limits as appended claim and scope.Table I
Table I I