UFEA: one accessory, three mounting systems

The situation

The UFEA is a spring-counterbalanced extrusion assembly for vertical monitor adjustment. It was a legacy product that needed an adapter to work with Humanscale's new quick-attach mounting system.

What I did

• Redesigned it to mount to three Humanscale systems instead of one.
• Moved the pivot from between the UFEA and the tilt mechanism to between the UFEA and the monitor, which removed a hazardous mode of operation.
• Ran a DFMEA down to the component level, more than 30 failure modes, with risk priority numbers for each and mitigation for anything over 100.
• Drew all new and modified parts and assemblies.
• Cut tooling cost by choosing a lower-volume process for slow-moving SKUs and by negotiating down the stamping and forming dies.
• Reviewed first-article parts and inspection reports with an overseas vendor and resolved out-of-tolerance dimensions before release.
• Wrote test plans and ran EVT and DVT validation, with life-cycle testing coordinated at the supplier.
• Kept the schedule in MS Project, held weekly cross-functional reviews, and handed off to the operations project manager with a full design record.

A design I got wrong, and how I caught it

I designed the mounting point as a modular bracket, compatible in both directions, and chose sheet metal for its ductility under shock. In destructive testing, a 20 lb monitor dropped from 8 inches, the bracket survived but deformed, two keying tabs pulled out, and the monitor could swing free.

That is exactly what engineering validation testing is for. The fix was a backing plate that confines the deformation to safe areas.