Leica GPS1200 Series Technical Reference Manual page 811

Diagram
COGO
COGO traverse calculation with offset for a single point
P3
d3
d1
P0
GPS12_106
COGO traverse calculation without offset for multiple points
d2
d1
P0
GPS12_063
P1
Known
d2
P0 Known point
α
P2
d1
d2
d3
Unknown
P1 COGO point without offset
P2 COGO point with positive offset
P3 COGO point with negative offset
Known
P0 Known point
α
d4
α
α
α
d1
d2
d3
d3
d4
GPS1200
Direction from P0 to P1
Distance between P0 and P1
Positive offset to the right
Negative offset to the left
1 Direction from P0 to P1
2 Direction from P1 to P2
3 Direction from P2 to P3
4 Direction from P2 to P4
Distance between P0 and P1
Distance between P1 and P2
Distance between P2 and P3
Distance between P2 and P4
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