Patent ID: 11875534
Assignee: GUANGDONG UNIVERSITY OF TECHNOLOGY
Field: Computer technology (Electrical engineering)
Classification: CPC G  B  Y | IPC B  G

Claim 8:
9. The pose estimation method for an unmanned aerial vehicle based on point, line and plane feature fusion according to claim 8, characterized in that the step S8 comprises: extracting a plane-linear feature from the two adjacent frames, recording the plane-linear feature as {πic,Ljc,kpπic} and {πmr,Lnr,kpπir}, wherein c represents the current frame, r represents a reference frame, πic represents the ith plane feature extracted in the current frame, Ljc represents the jth linear feature extracted in the current frame, kpπic represents a feature point set of the ith plane in the current frame, πmr represents the mth plane feature extracted in the reference frame, Lnr represents the nth linear feature extracted in the reference frame, and kpπir represents a feature point set of the ith plane in the reference frame; and respectively constructing the corresponding point-line-plane association graph; firstly, matching the feature points of two frames, wherein if there are two feature point sets kpπkc and kpπgr, and a matching point pair thereof being larger than the set threshold thkp, it is considered that the plane πkc of the current frame and the plane πgr of the reference frame are matched in color, so as to obtain a set of planes Oπ={πac,πbr} that match in color; for each plane pair {πa0c,πb0r} in Oπ, in a neighborhood space Ω, where πa0c corresponds to a PPS coordinate, finding out all the plane pairs Oπfh={πfc,πbr} with the PPS coordinate being in Ω, that satisfy Oπfh∈Oπ and πfc, and using an edge relationship thereof to calculate the matching score:, S
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wherein NQπfh represents the number of plane pairs in the Oπfh, eπcf,πca represents an edge of the plane πf0c and the plane πa0c and eπrh,πrbT represents an edge of the plane πh0r and the plane πb0r, {πf0c,πh0r}∈Oπfh, and if Scπ<3, it is considered that the plane pairs {πa0c,πb0r} are correctly matched plane pairs, otherwise, the plane pairs are considered to be mismatched plane pairs and are removed from the set Oπ;
for each line in the extracted linear feature sets Ljc and Lnr, respectively finding out, by means of the respective point-line-plane association graph, an associated plane set which belongs to the set Oπ, after the mismatched plane pairs are removed; constraining the edge between an associated plane of Oπ to which the line belongs by using a least square method, so as to realize the matching between lines; wherein a constraint function ScL is:

ScL=argmin(∥Σ|eLcj,πc·diag(10,1,0.2)·eLrn,πrT|∥2)

wherein eLcj,πc and eLrn,πr respectively represent the edge between the associated planes to which the line belongs to Oπ; ScL is a loss function of the least square method, and a matching process is to use the least square method to iteratively update ScL and obtain a result that makes the shortest line matches; ∥Σ|eLcj,πc·diag(10,1,0.2)·eLrn,πrT|∥2 in a ScL function represents a loss value obtained by means of a correlation graph assuming that the line and the line Lnr are matched line pairs.