GPS Positioning of Some Objectives Which are Situated at Great Distances from the Roads by Means of a “Mobile Slide Monitor – MSM” - Cartography: A Tool for Spatial Analysis - page 172

- The reference point relatively to which the positioning measurements of the sighted

target are achieved, is constituted by the central point L of the video camera lens, which
is placed at the focal distance f from the video camera matrix sensor;

- It arises the problem to establish the geographic coordinates for the reference point L on

the basis of the same type of coordinates of the point IMU;

- The distance between the points IMU and L presents the following components:

a. On the

x  axis of the vehicle coordinate system:

Dmf

    

cos cos ; (1)

x

C C

b. On the y  axis of the vehicle coordinate system:

V

Dnf

    

sin cos ; (2)

y C C

V

c. On the z  axis of the vehicle coordinate system:

V

Dpf

   

sin . (3)

z C

V

In the above-mentioned relations, by m , n and p were noted the components, on the axis
, ,
VVV

xyz , of the distance between the point IMU and the central point C of the video
camera sensor.

By  and  were noted the video camera montage (fixed) angles in relation with the
vehicle coordinate system.

DDD , ,

x y z

V V V

- In order to compute the offset components, in relation with the reference system

, ,
VVV

xyz , with IMU point as origin, the following group (2) of relations is used:

 

DD   cos  cos   sin sin  sin  D

x x  y 

V

V V

 

cos  sin   D cos  sin  sin  sin cos 

z 

V

 

DD   cos  sin   sin sin  cos  D

y x  y 

V

V V

 

cos  cos   D sin  sin  sin cos  cos 

z 

V

       
In these relations by Ψ, Θ and Φ, were noted the rotational angles of the lab vehicle, angles
which were measured by the Inertial Unite IMU in relation with the reference system ( x , y
and z ) of the current location.

DD cos sin D sin D cos cos

  

z x y z

V

V V V