Magnetic labeling location method based on omnidirectional distribution magnetic sourceTechnical field
The present invention relates to a kind of tracing and positioning technology, in particular to a kind of magnetic labeling location side based on omnidirectional distribution magnetic sourceMethod.
Background technique
In Moving Objects location technology, location requirement especially in field of biomedicine, it is often required that location technologyUsing it is non-contact, propagate independent of medium and the characteristics such as without side-effects, such as the capsule endoscope positioning of gastrointestinal tract detection,Or oral cavity internal tongue motion detection for aphasia treatment etc..Magnetic marker technology because its have it is untouchable, propagate notDependent on the advantages such as medium and the mathematical model of maturation, and the positioning for being widely used in solution field of biomedicine is askedTopic.
Magnetic labeling location method is by being fixed on object to be tracked for excitation source, as marker, with the space of excitation sourceThe spatial position and posture of position and posture characterization object to be tracked, pass through the spatial magnetic field of solution excitation source excitation and itsThe mathematical model met between Position and orientation parameters realizes label source localization, referred to as magnetic reverse temperature intensity.In source localizationIn technology, the signal-to-noise ratio of the space magnetic field magnetic flux distribution information of magnetic source excitation has the precision of magnetic reverse temperature intensity resultSignificantly influence.High space magnetic field magnetic flux distribution metrical information signal-to-noise ratio, will obtain higher positioning accuracy.However,The space magnetic field intensity of excitation source excitation can between observation point and excitation source distance tempestuously decay.Further, since excitationThe dipole moment in source has directive property, so that observing point vector close to orthogonal when dipole moment and the excitation source of excitation source are directed towardWhen, the excitation source excitation space magnetic field magnetic flux density intensity that observation point detects is weaker.Therefore, how in existing magnetic orientation skillOn the basis of art, weakens the influence because of excitation source dipole moment directive property to detection gained magnetic field strength, obtains higher signal-to-noise ratio,Realize high-precision source localization the result is that magnetic labeling location technical field of research emphasis.
Summary of the invention
The present invention be directed to the location technology based on magnetic marker there are the problem of, propose a kind of based on omnidirectional distribution magnetic sourceMagnetic labeling location method, realize high-precision, quickly positioning.
The technical solution of the present invention is as follows: a kind of magnetic labeling location method based on omnidirectional distribution magnetic source, specifically includes as followsStep:
1) omnidirectional distribution magnetic source is placed in object to be tracked, for marking object to be tracked, omnidirectional distribution magnetic source is by twoA independent magnetic source is constituted, and magnetic source uses dipole model of magnetic, and the dipole moment of two magnetic sources is orthogonal, forms orthogonal pointCloth, orthogonal magnetic source form spatial magnetic field around object to be tracked；
2) the magnetic measurement sensor array known to global rectangular coordinate system spatial location and posture is utilized, is measuring this justThe space magnetic field magnetic flux distribution situation for handing over magnetic source to establish, magnetic measurement sensor are uniaxial or multiaxises；
3) based on magnetic measurement sensor array measurement institute known to magnetic source dipole model of magnetic and spatial position and postureSpace magnetic field magnetic flux distribution information in sensor position, establish orthogonal magnetic source real-time spatial position and attitude parameterConverse solved model；
4) by optimization algorithm, orthogonal magnetic source real-time spatial position and attitude parameter solving model is solved, is obtained wait trackObject real-time spatial position and posture.
Two independent magnetic sources of omnidirectional distribution magnetic source are all made of magnetic dipole and are modeled in the step 1), two magnetic sourcesLocation parameter be respectively rpAnd rp⊥, the dipole moment intensity of two magnetic sources is respectively m and m⊥, the dipole moment side of two magnetic sourcesTo respectively M and M⊥, and their dipole moment is mutually perpendicular to, that is, meets MM⊥=0；
I-th of magnetic measurement sensor location parameter in global rectangular coordinate system x-y-z is rsi, according to two independent magnetic sourcesThe theoretical calculation of the space magnetic field magnetic flux distribution of magnetic dipole excitation, obtains the space of i-th of magnetic measurement sensor positionMagnetic field flux Density Distribution value is the space magnetic field magnetic flux distribution B of two independent magnetic source excitationsciAnd Bci⊥Linear superpositionBΣc(i),
μ0For space permeability.
Magnetic measurement sensor array is by N number of uniaxial or multi-axial sensor according to certain formal distribution in the step 2)Composition, wherein the Position and orientation parameters of i-th of magnetic measurement sensor are expressed as rsiAnd Msi, magnetic measurement sensor array realityMeasurement gained space magnetic field magnetic flux distribution is { Bm,
{ Bm }={ Bm (1), Bm (2) ..., Bm (i) ... Bm (N) }, (i=1,2 ..., N)；
Orthogonal magnetic source real-time spatial position is established based on criterion of least squares and the Converse solved model of attitude parameter is
By Least-squares minimization algorithm solution formula, orthogonal magnetic source real-time spatial position parameter r is obtainedpAnd rp⊥, andSpatial attitude parameter M and M⊥。
The object to be tracked and its nearby not except magnetic field source of the label in addition to omnidirectional distribution magnetic source or ferromagneticProperty material, ambient noise magnetic field is considered as that intensity is permanent, demarcated by measuring in advance, and by difference method it is directIt weeds out.
The beneficial effects of the present invention are: the present invention is based on the magnetic labeling location methods of omnidirectional distribution magnetic source, by magnetic dipoleThe mutually perpendicular omnidirectional distribution magnetic source of square is fixed on object to be tracked, establishes space magnetic field, pass through position and attitude as markerKnown magnetic measurement sensor obtains in sensor position, by the magnetic flux distribution information for the space magnetic field that magnetic source is established, knotMagnetic source forward direction dipole model of magnetic and measurement gained space magnetic field magnetic flux distribution information are closed, the real-time of object to be tracked is establishedSpatial position and the Converse solved mathematical model of attitude parameter realize object to be tracked space motion path by optimization algorithmThe identification of the online real-time tracing of position and posture.The present invention realizes that the magnetic source of high s/n ratio excites space by omnidirectional distribution magnetic sourceIt obtains to Distribution of Magnetic Field information, the raising of magnetic source position, posture information solving precision is realized, to mention based on magnetic labeling location technologyA kind of accuracy method is supplied.
Detailed description of the invention
Fig. 1 is that the present invention is based on the magnetic labeling location method schematic diagrams of omnidirectional distribution magnetic source.
Specific embodiment
It is real below in order to be easy to understand the technical means, the creative features, the aims and the efficiencies achieved by the present inventionExample combination attached drawing is applied to be specifically addressed the magnetic labeling location method the present invention is based on omnidirectional distribution magnetic source.
A kind of magnetic labeling location method based on omnidirectional distribution magnetic source mainly comprises the steps that
Step 1, selects the omnidirectional distribution magnetic source for marking object to be tracked, and omnidirectional distribution magnetic source is independent by twoMagnetic source is constituted, and magnetic source includes two kinds of forms of permanent magnet or electromagnetic coil, and the dipole moment of two magnetic sources is orthogonal, is formed orthogonalDistribution, orthogonal magnetic source form spatial magnetic field around object to be tracked, establish magnetic source dipole model of magnetic.
Step 2 establishes global rectangular coordinate system x-y-z, using known to global rectangular coordinate system spatial location and postureMagnetic measurement sensor array, measure the space magnetic field magnetic flux distribution situation that the orthogonal magnetic source is established, magnetic measurement sensorIt can be uniaxial or multiaxis.
Step 3 is surveyed based on magnetic measurement sensor array known to magnetic source dipole model of magnetic and spatial position and postureSpace magnetic field magnetic flux distribution information in amount gained sensor position, establishes orthogonal magnetic source real-time spatial position and posture ginsengSeveral Converse solved models.
Step 4 solves orthogonal magnetic source real-time spatial position and attitude parameter solving model by optimization algorithm, obtain toTrack object real-time spatial position and posture.
As shown in Figure 1, two independent magnetic sources, magnetic source 1 and magnetic source 2 are placed in global rectangular coordinate system x-y-z, omnidirectional distributionLabel magnetic source is constituted, they can be used magnetic dipole and are modeled, wherein the location parameter of magnetic source 1 is expressed as rp, magnetic source 2Location parameter be expressed as rp⊥, the dipole moment intensity of magnetic source 1 and dipole moment direction are expressed as m and M, the magnetic of magnetic source 2Dipole moment intensity and dipole moment direction are expressed as m⊥And M⊥, and their dipole moment is mutually perpendicular to, that is, meets MM⊥=0.
N number of uniaxial or multi-axial sensor constitutes magnetic measurement sensor array according to certain formal distribution, wherein theThe Position and orientation parameters of i magnetic measurement sensor are expressed as rsiAnd Msi, measurement result is B thereonm(i).So, Magnetic testi passesSpace magnetic field magnetic flux distribution obtained by sensor array actual measurement is { Bm, { Bm }={ Bm (1), Bm (2) ..., Bm (i) ...Bm (N) }, (i=1,2 ..., N) (1)
Each magnetic measurement sensor measurement result BmIt (i) is the space magnetic field B of orthogonal magnetic source excitationciAnd Bci⊥It makes an uproar with environmentSound magnetic field BnSuperposition
Bm(i)=Bci+Bci⊥+Bn
On all magnetic measurement sensors, ambient noise magnetic field is considered as that intensity is permanent, thus can be by pre-First measurement is demarcated, and is directly weeded out by difference method.
I-th of magnetic measurement sensor location parameter in global rectangular coordinate system x-y-z is rsi, i-th of Magnetic testi sensingThe theoretical distribution B of the space magnetic field magnetic flux distribution excited respectively on device position by two independent magnetic source magnetic dipolesciWithBci⊥,
In formula (2) and (3), μ0For space permeability.
Positioned at rsiPlace, by the calculated value B for the space magnetic field magnetic flux distribution that omnidirectional distribution magnetic source excitesΣc(i) it isIt is made of the linear superposition of the space magnetic field magnetic flux distribution of two independent magnetic source excitations of omnidirectional distribution magnetic source,
Orthogonal magnetic source real-time spatial position is established based on criterion of least squares and the Converse solved model of attitude parameter is f (rp,rp⊥,M,M⊥),
By Least-squares minimization algorithm solution formula (5), orthogonal magnetic source real-time spatial position parameter r is obtainedpAnd rp⊥, withAnd spatial attitude parameter M and M⊥。
A kind of magnetic labeling location method based on omnidirectional distribution magnetic source is present embodiments provided, dipole moment is orthogonalOmnidirectional distribution magnetic source as marker, be fixed on object to be tracked, establish space magnetic field, examined by magnetic known to position and attitudeSensor array is surveyed, sensor position { r is obtainedsOn by magnetic source establish space magnetic field magnetic flux distribution information, in conjunction with magneticSource forward direction dipole model of magnetic calculates in gained sensor position by the theoretical value { B of magnetic source excitation spatial magnetic fieldΣcAnd passSpace magnetic field magnetic flux density actual distribution information { B in this position obtained by sensor array measurementm, establish the real-time of object to be trackedSpatial position and the Converse solved mathematical model f (r of attitude parameterp,rp⊥,M,M⊥), by optimization algorithm, realize object to be trackedThe identification of the online real-time tracing of space motion path position and posture.The present embodiment realizes high s/n ratio by omnidirectional distribution magnetic sourceMagnetic source excitation spatial magnetic field information obtain, realize magnetic source position, posture information solving precision raising, for based on magneticLabel location technology provides a kind of accuracy method.
Above-mentioned implementation method is preferred case of the invention, the protection scope being not intended to limit the invention.