
110 Virtual Reality: Concepts and Technologies
Figure 6.1 Electromagnetic field around a coil
values of the created magnetic field B in polar coordinates are r and θ in a plane
containing the axis of the coil (Figure 6.1).
B
r
= µ
o
NIR
2
cos(θ)/2r
3
(6.2)
and
B
θ
= µ
o
NIR
2
sin(θ)/4r
3
(6.3)
with geometric positions: r R and r L, coil of N windings, of radius R and length L,
vacuum permeability µ
o
, wavelength λ
With a coil of the transmitter, we create an alternating magnetic field, whose
strength depends on r and θ. The direction and strength of this field are determined
with the three orthogonally aligned coils of the receiver as they receive the measured
electric ...