18 Jan

Vision Inspection to Reduce Bottle Breakage in Beverage Case Sealer Systems

The problem – Breakage and downtime at the beverage bottle case sealer:

A common problem in bottling operations is inspection of bottles in the case prior to sealing the case for shipping to the customer.  Case sealing machines are unable to detect bottles that are improperly seated in the case.  Attempting to seal cases with improperly seated or misplaced bottles results in bottle breakage and damage to the sealing machines along with glass and other contamination issues that can result in significant production down time.

KTM Research can provide advanced 3D vision systems to inspect cases before they enter the case sealing machine, stopping the line before breakage occurs if any misplaced or missing bottles are detected.

Bottle Inspection:

Bottle inspection on the bottle case sealer looks for proper placement of the bottles in the case prior to case sealing.  The two key modes of failure are protruding bottles and misplaced bottles.  A secondary mode of failure is a missing bottle that can lead to an angry customer one bottle short of a full case.

Misplaced and protruding bottles in a 24 bottle case.

Bottles that are not fully seated are those whose tops are more than 1.25” above the normal bottle top height.  Any bottle exceeding 1.25” should be considered a failure and rejected before the case sealer.  Misplaced bottles are any bottle that is not in a slot.  Often times these bottles lay on top of other bottles and protrude high enough to be broken by the case sealer.  Any cases with a misplaced bottle should also be rejected.

The solution – LMI’s Gocator Laser Profile Scanner:

Bottle inspection is an application ideal for a laser profile scanner.  Laser profile scanners use a laser line along with a camera to interpret the height profile at the intersection of the laser line and the cross-section of the shape being scanned.  If the part being inspected is moved under the laser profile sensor, a height map (z-height) is generated by sampling the laser line profile as the part is scanned.  The laser profiler includes internal processing capabilities that may be able analyze the profiles and provide an output signal indicating whether the case passed or failed the inspection.

Laser profilers are somewhat sensitive to gloss and reflectiveness of the surface.  If there are large differences between different products, a calibration may be required at the beginning of the product batch to recalibrate the sensor.  For instance, if one batch of bottles has shiny foil wrapping while another is covered in matte black labels, recalibration may be needed.

LMI Gocator basic operation principle: A laser scanner images a moving target and captures height profile information for interpretation.

See the case in 3D – See the problems, avoid the breakage:

The laser profiler is the best solution for bottle inspection.  Both the misplaced and protruding bottle conditions are easily detectable in the laser profile.  If desired, missing bottles are also easily detectable so that corrective action can be taken.

The image below is apseudo-color presentation of profile data taken from a case of bottles with some misplaced, missing, and protruding bottles.  Colors represent z-height values from the profile with red indicating the highest areas scanned.  The heights shown in the legend are roughly equivalent to millimeters in this case.  Blue is the bottom of the case and reds are the bottle caps.  While not obvious from the pseudo-color ranges, the protruding bottle has a z-height value of 258 versus the seated bottle height of 233 (25mm difference), which corresponds very closely to the actual protruding bottle height of approximately 1 inch above the seated bottles.

3D profile views of missing and protruding bottles taken with a LMI Gocator.

A 3D profile view is shown to more clearly depict the differences in height between the protruding bottle and the seated bottles.  A misplaced bottle is also detectable in the profile data.  The image below shows the profile and 3D views with a misplaced bottle.  The bottle label is key feature to detect a misplaced bottle.  It is a large area that will have a z-height equal or above the bottle caps.  This condition is also often accompanied by a missing bottle detected in the case (blue square).


A misplaced and a missing bottle in a profile and a 3D view taken with LMI’s Gocator.

Note that all the images above are missing a row of bottles at the bottom.  This is due to the shadow of the single profile scanner we used for these preliminary test scans.  Since the bottle inspection requires seeing all the bottle caps, the configuration for the bottle inspection will require two profilers configured to cover the full area inside the case.  The image below depicts the bottle inspection configuration.

Two LMI Gocators operating in “buddy mode” to fully capture height information from inside of a 24 bottle case.

This “buddy” configuration is a standard feature of the LMI Gocator laser profiler, where two Gocators work together to produce a single height map of the complete case interior.  Processing of the height map is then accomplished by the laser profiler and an external PC for inspection analysis.

About KTM Research:

KTM Research is an engineering firm that specializes in industrial machine vision systems for quality control and vision-guided robotics.  Formed in 2009, we are located in Tualatin, Oregon.  We serve industries in the fields of advanced manufacturing, consumer electronics, bio-tech, food and beverage, research, and logistics.  Our systems have been successfully used by customers across North America and Asia.

Our goal at KTM Research is to be the first call you make when faced with a vision challenge.  Our team of engineers view themselves as an extension of your organization and strive to be your trusted vision partner.  Our success is our clients’ success.  Our collaborative approach to projects with our conservative and robust design process allows KTM Research to successfully complete projects that many others cannot.

Contact KTM Research at info@ktmresearch.com for more information on our vision solutions.