© Nadeem Haidary 2009

MSA Bypass Shuttle

Falls are the leading cause of death in the construction industry, which itself accounts for the largest number of occupational deaths. Working on a project sponsored by Mine Safety Appliances, our interdisciplinary team of designers, researchers and engineers sought a solution to an area that has seen little innovation. The result was a completely new kind of shuttle that allows workers to bypass each other on a horizontal lifeline, streamlining a time-consuming and potentially dangerous process. Preliminary patents have been filed.

In the first phase of the project, we were given the task of finding opportunities for a safer environment for commercial construction. After brainstorming over a hundred different opportunities, we found that fall protection offered the greatest opportunity to create positive change.

Through a visit to a large construction site, our team learned that the main defense against elevated falls are horizontal lifeline systems, many of which are "homemade" contraptions.

On another site visit, we noticed a worker illicitly working over an edge without a safety harness. With restrictive lifelines and cumbersome harnesses, compliance is a very big problem.

There is currently no solution to allow these workers to pass each other.

Borrowing an existing lifeline system from MSA, we conducted a task analysis of setting and bypassing on a lifeline. Two trees stand in for I-beams.

These sketches show the later development of a bypass shuttle. The shuttle's form alludes to MSA's best known product, the V-guard hard hat. These drawings came after several rounds of concept development exploring areas like tangle control and a hub-based lifeline system.

A basic stress analysis helped us to evaluate a shuttle design that would be stamped from a single plate of steel. Our final design increased radii, was bulked up and called for hot forging.

The bypass shuttle works by using its inherent geometry rather than any sophisticated technology. The gap is large enough for the other shuttle to pass through when turned 180°, but not large enough to come off the line. In a product sector that has almost no differentiation between brands, we recommended that MSA make their logo and brand visible.

Our marketing plan included a rollout strategy, approximate manufacturing costs as well as a conjoint analysis to determine the ideal price point.