A six-axis KUKA robot is being used to perform quality control checks on insulin pens as part of a new automated materials testing system developed by Zwick.
The top machine manufacturer, based in Ulm-Einsingen, Germany, has chosen a high accuracy KUKA KR 5 sixx model for its roboTest R cell, which is designed to measure various functions such as dose setting and actuation force in a continuous process.
The pens, which enable diabetics to self-administer insulin injections, are subject to strict quality assurance controls so product testing needs to deliver reliable and repeatable results.
According to Zwick, using the KUKA robot to load the pens from a magazine and accurately position them in the system avoids the problems usually associated with manual test methods. For instance, results may be distorted if the plastic specimen is touched by hand as body heat can affect the material’s characteristics.
In addition, product quality is improved as the robot is able to achieve repeatable results of +/-0.02mm while short cycle times mean a more efficient testing procedure as a higher number of specimens can be processed.
The test methods for the two axes can be modified and combined as required. Also, the robot arm can be moved to a ‘park’ position so that the system operator can perform manual tests whenever required.
“A production process for medical products must be seamlessly documented in accordance with the necessary regulations and using automation with KUKA robots ensures precisely planned and traceable sequences,” explained Robert Kaifler, Zwick’s automation product manager.
The new robotic testing system is not only suitable for checking other medical products such as dental syringes and childproof medicine caps, but can also be easily integrated with other materials testing equipment.
Zwick has been using KUKA robots for automating its machines for over 10 years with 80% of these systems employed in destructive materials testing applications.