Zühlke – Empowering Ideas

Medical Device and Healthcare

Product optimization through design review

Roche Diagnostics
  • Roche wants to bring a product to market on time  
  • The construction is already optimized during the development  
  • Safety and quality of the product are improved 

In this design review, Zühlke examined the reliability of production and substantially improved the use characteristics of a medical product.


Over 120 million people suffer from type 2 diabetes worldwide. Many of them have to take blood samples daily. Patients are given finger-pricking devices to help them carry out these procedures easily and painlessly. These devices must operate extremely reliably and are produced in large quantities. In this project, Zühlke’s task was to review the design of a new generation of these devices before they were approved for mass production. The manufacturer wanted to launch the product on schedule and in accordance with high quality standards. 


The review team started by reviewing the safe operation of the device. This product is made almost completely out of plastic. Careful attention was therefore paid to the material selected and pairings and to whether the design was appropriate for the material (wall thicknesses, back-cuts at curves). Critical components (e.g. springs) were examined with FEM for possible overstressing and tolerance chains were re-calculated (statistically and worst case). The Zühlke engineers passed their review findings on to the developers on an ongoing basis, so the latter could make immediate improvements in the design. A second priority was the readiness of assembly. Experts used MTM methods (Methods-Time Measurement) to optimise the assembly and calculate the assembly time.