Bonito Technical Manual
V2.4.0
52
Parameters and commands
PIV mode (bit group p)
Particle Image Velocimetry (PIV) is a contact-free method for tracking and visu-
alizing the movement of particles that travel at high velocity within liquids or
gases. At first, the position of identical particles in two subsequent images is
determined. This allows to calculate the speed and direction of the particles in
every part of the acquired images.
If the PIV mode is enabled, the camera outputs two images for each trigger
event. This allows minimizing the time between the exposure of the two images
to the possible minimum. This improves the measuring precision at high veloci-
ties.
Particle image velocimetry only evaluates images of the same pair.
Figure 26: Exposure timing mode, M=3, flow diagram
Parameter
Value
Trigger High Duration
(Sync Pulse)
t
L
< t
TH
< F * t
TR
– t
L
Exposure Jitter
0 < t
j
< t
L
Exposure Time
t
Exp
= E * t
TR
– t
L
± t
j
Frame Duration
F * t
TR
≥ max (t
FDmin
+ t
L
, E * t
TR
+ t
L
)
Table 15: Exposure timing mode, M=3, timing parameters
