Date of Defense



Industrial and Manufacturing Engineering

First Advisor

Dr. Tycho Fredericks

Second Advisor

Dr. Steven Butt


Productivity and ergonomic issues are important concepts in many organizations today. Combined, they allow for a more flexible organization with greater profit opportunities and less employee injuries, ultimately resulting in an overall cost savings. These concepts were the focus of this project.

The project involved analyzing and redesigning the current production line of the Stryker Medical stair chair. The purpose of the project was to re-design the existing manufacturing line to double its production capacity and improve ergonomic issues. The project is supported by an examination of material flow and a cost/benefit analysis.

To serve as a guide for the project, a detailed project plan and timeline were created. Additionally, a selected review of literature was created to identify techniques to be used in our analysis. A thorough investigation was conducted to narrow down design options, and the final proposal will be presented to our corporate sponsors for their consideration. Tools used in the project included ergonomic analysis, line balancing, Crystal Ball Simulation, and computer aided design.

The recommended design will eliminate lifting, and thus decrease the risk of lower-back injuries. The ergonomic analysis indicated that the current process poses a potential risk for injury in the hand, wrist, upper arm, neck, and trunk of the body. The proposed solution, to address ergonomic and production capacity issues, is to purchase new equipment, rearrange current elements, and add an additional operator to the line. Our cost/benefit analysis justifies these recommendations based on a higher profit margin as well as an increase in the average chair output per operator.

By implementing this new design, Stryker can expect a decreased risk of operator injuries and increases in production capacity. Our recommendation would also yield a significant increase in efficiency; from 6 chairs/operator/day to 8.4 chairs/operator/day. This improvement would also increase the average profit margin/chair from $1450 to $1454.57. Our final recommendations address the design criteria set forth by Stryker Medical while significantly impacting their bottom line.

Access Setting

Honors Thesis-Campus Only