Seamless Navigation, 3D Reconstruction, Thermographic and Semantic Mapping for Building Inspection

. 2022 Jun 23;22(13):4745. doi: 10.3390/s22134745

Algorithm 1 Selection logic for switching from local to global navigation

Data AprilTag triangulation reading, local IPS pose, global GPS reference coordinate
Result 6 DoF homogenous transformation & associated covariance matrix

1:
append ← true
2:
if current tag ID ∈ ID list then
3:
if current tag ID = last item in ID list then
4:
if current tag Euclidean distance > Euclidean distance of last item in ID list then
5:
append ← false
6:
end if
7:
end if
8:
end if
9:
if append then
10:
ID list ← add current tag ID
11:
local point list ← calculate local position from IPS pose & AprilTag triangulation
12:
global point list ← calculate ECEF position from GPS reference
13:
end if
14:
if number of unique IDs in ID list ≥ minimum ID list size then
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(transformation, covariance) ← 6 DoF estimation from local & global point lists
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valid trafo ← true
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for each item in local point list do
18:
valid trafo ← residual among global & transformed local points < max. residual
19:
end for
20:
if valid trafo then
21:
return (transformation, covariance)
22:
end if
23:
end if