Speedy tyre inspection.
Non-contact laser-based profile measurement sensors
from Micro-Epsilon, have solved an inline inspection
problem for a leading tyre manufacturer.
Continental Tyres is now using three scanCONTROL 2800 2D13D laser
profile sensors from Micro-Epsilon, on a test rig developed by Czech
machine builder MicroStep, which inspects individual tyres in less than
one second, enabling 100% inspection of tyres from the production line.
Rather than using multiple laser-based point sensors or capacitive sensors,
the scanCONTROL 2800 sensors measure the tyre's profile using a laser
line, on which multiple measurement points can be acquired and analysed.
Previously, Continental used capacitive sensors and laser-based optical
point sensors to inspect tyres. The capacitive method could not differentiate
patterns, symbols or legends on the tyre from genuine surface defects such
as bulges. While with the laser point sensors, not oniy would multiple sensors
have to be used to acquire surface defect data, but the sensors could not
cope with the high throughput rate on the test rig or with the reflection
properties of newly-produced, black, shiny rubber tyres.
The scanCONTROL 2800 sensor has an integrated, highly-sensitive CMOS
array, which enables measurements of almost any shiny, reflective or
transparent surface, independent of the reflection from the target. This means
accuracy, resolution and reliability are achieved, even at high measurement
speeds. Using special software algorithms, logos and symbols on the tyre
can be detected and removed when analysing the acquired data.
The measurement system consists of three scanCONTROL 2800 sensors
and a controller. The measurement data is output from the controller via a
Firewire interface to the customer's in-house developed analysis/evaluation
software.
Other potential applications include contour measurement, robot guidance,
door gap alignment, position measurement, rail profile, groove measurement,
coplanarity measurement and flatness measurement.
Micro-Epsilon's latest version, the scanCONTROL 2810, was unveiled at
the Hanover Fair last year and launched officially in Autumn 2005. This new
sensor builds on the success of the scanCONTROL 2800 but is even easier
to integrate, set up and configure for individual applications. Using the same
laser line triangulation measurement principle as the scanCONTROL 2800,
it is capable of measuring up to 256,000 points per second.
The unit is suited for real time quality inspection or online process guidance.
Depending on the resolution and size of the measurement range, a profile
frequency of up to 4,000 profiles per second can be attained. Applications
include detecting weld seams, beads of adhesive, edges, angles and
detecting grooves, channels and gaps.
The scanCONTROL 2810 system comprises a sensor and integrated
controller, which calculates the dimensions of the bead or groove. The
system works in two ways: a stationary mode with the sensor fixed and
looking at moving targets, or in combination with a motion control device
or robot.
The sensor uses an innovative CMOS array with a real time, high speed
electronic shutter, which captures the entire profile and processes the
information instantaneously.
The controller evaluates the measurement data and provides control
signals via analogue or digital outputs. The system can be easily
configured using the parameter software included within the sensor
package. Parameters that can be configured include area, height
and width of the bead.
_________________________________________________________
April 2006
