Method for managing crossovers in the tracking of mobile objects, and associated device

A method for managing track crossovers implemented by at least one device for tracking mobile objects comprising a group of at least one sensor, the tracking of mobile objects consisting in estimating a set of tracks corresponding to the various mobile objects perceived by the group of at least one sensor, each track corresponding to a set of successive plots representing the movement of a given mobile object, said method being comprising, for each track at a given time, a step Stp1 of testing in order to determine whether the track in question is ambiguous or not at the given time, a track k being said to be unambiguous at the time tl if it respects the relationship:

• ∑
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• =
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• ≠
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• or if for any track j≠k it respects the relationship:
• |∥Ĉl−1k+Âl−1k(tl−tl−1)−Ĉl−1j−Âl−1j(tl−tl−1)∥|>S
• in which relationships:
• K is the total number of tracks created up to the time tl−1,
• {circumflex over (q)}l−1j is the estimate of the proportion of plots classed in track j up to the time tl−1,
• g(.) is a probability density,
• Ĉl−1j=Âl−1jtl−1+{circumflex over (B)}l−1j is the estimate of the position vector of the track j at the time tl−1,
• Âl−1j is the estimate of the velocity of the track j at the time tl−1 and {circumflex over (B)}l−1j the estimate of the position vector of the track j at the time t=0,
• ε is a coefficient. In one embodiment this coefficient is 0.1,
• {circumflex over (r)}l−1k={circumflex over (q)}″l−1k/c where {circumflex over (q)}″l−1k is the estimate of the proportion of the plots Xn classed in a track far removed from the track k and c the integral of the domain of the admissible measurements
• |∥.∥| represents the norm defined for a vector X=(xp) by
• 
• 
• X
• 
• 
• =
• sup
• 
• (
• 
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• p
• 
• σ
• p
• )
• where σp is the standard deviation for the pth component of X in the density g(X),
• S is a predefined threshold,
• and, if the track is ambiguous, a step Stp2 of specific processing of the estimate of the track.