How Do 3D Dimensioners Work?
Get to Know the Limits of Your Dimensioner
3D vision-based dimensioners are becoming more popular thanks to
their cost-effectiveness and easy-to-deploy nature. As the
dimensioning paradigm shifts from primitive ultrasound/infrared
sensors and expensive lasers to 3D vision cubing systems, some
questions may arise among users.
How Does 3D Vision
Dimensioning Differ From Others?
3D cameras capture the distance of their surroundings
in a snapshot instead of their colors as regular 2D cameras do. 3D
vision-based dimensioners process captured distance frames and
extract the object of interest. Then objects dimensions are measured
using the distance data. One of the advantages of 3D image
processing is that every visible part of the box is taken into
account in dimension measurement.
In infrared or
ultrasound point-sensor based dimensioners, the dimensions of
objects are measured only using 3 point measurements assuming that
the object is perfectly rectangular. However, this is never the
case; no box is perfectly rectangular.
Laser-based
dimensioners also create a 3D representation of objects but they do
it by scanning objects line by line instead of in a single image as
3D cameras do and hence they are not suitable for static
measurements.
How Does 3D Vision Dimensioning Differ From
Others?
Just like other cameras, 3D cameras have a cone-shaped
field of view. The objects that are completely in the field of view
of cameras can be measured correctly. Hence, the dimensioning
capacity of 3D vision dimensioners is bounded by how they can see.
Wider objects can be measured if their height is low.
Some
vendors prefer to specify the dimensioning range per every edge as
in the table below but this can be very misleading for the
customers.
The table below does not tell you that your 3D
dimensioner can measure 100 x 100 x 100 cm sized object! In fact, it
just tells you that the maximum measurable size per edge is 100cm as
in 100 x 100 x 10cm and 10 x 10 x 100cm sized objects.
MIN. | MAX. | |
---|---|---|
Width | 5 | 100 |
Length | 5 | 100 |
Height | 5 | 100 |