Customer Challenge

This was a problem-solving collaborative operation between Quest Global and our client. The client had identified a situation where a mechanical lock was able to go into the “closed” position when the motor was off.

The issue seemed related to the access door tab being too shallow, and its lever being on the border of being obstructed.


  • To perform a technical investigation, identify the fault and provide an alternate design to overcome this problem.
  • Concept design and review through to PDR/DDR by reviews with structures, methods and CFT teams
  • Release all necessary drawings in VPM/PDM


  • Investigated the existing design of the door isolation system
  • Evaluated existing interfaces
  • Created concept designs
  • Validated concept proposals with our internal and external collaborators, including our safety specialists
  • Reviewed all manufacturability and assembly sequences


  • We generated an alternate concept
  • We presented design ideas in CFTs and selected appropriate concept for implementation
  • The design complies to all technical requirements
  • All documents and 3D renderings were released in VPM/PDM


  • An optimised design solution which meets the requirements of the end customer
  • The design complies with human factors and safety requirements
  • 3D design and drawings were produced for all levels up to production, ensuring every necessary stakeholder was able to examine the solution
  • The length of the door tab had been modified to ensure that the mechanical lock in the door isolation access cover did not close in the “motor off” position.