Modular Design of a Passive, Low-Cost Prosthetic Knee Mechanism to Enable Able-Bodied Kinematics for Users With Transfemoral Amputation

There is a significant need for low-cost, high-performance prosthetic knee technology for transfemoral amputees in India. Replicating able-bodied gait in amputees is biomechanically necessary to reduce the metabolic cost, and it is equally important to mitigate the socio-economic discrimination faced by amputees in developing countries due to their conspicuous gait deviations. This paper improves upon a previous study of a fully passive knee mechanism, addressing the issues identified in its user testing in India. This paper presents the design, analysis and bench-level testing of the three major functional modules of the new prosthetic knee architecture: (i) a four-bar latch mechanism for achieving stability during stance phase of walking, (ii) an early stance flexion module designed by implementing a fully adjustable mechanism, and (iii) a hydraulic rotary damping system for achieving smooth and reliable swing-phase control

Cost analysis and comparison of tray container style storage and stackable tote style storage

Thesis: M. Eng. in Advanced Manufacturing and Design, Massachusetts Institute of Technology, Department of Mechanical Engineering, 2018.Cataloged from PDF version of thesis.Includes bibliographical references (page 49).With the emerging interest in automated distribution centers, shelves operated by mobile robots are also rising in importance. This paper focuses on comparing the cost of two potential shelf designs for storing product in an automated distribution center, a tray container style shelf and a stackable tote style shelf. Tray container style shelf has lower manufacturing costs, assembly cost and time, while stackable tote style shelf had competitive edge on packaging and shipping costs, and space utilization. The manufacturing cost, packaging cost, and shipping costs $174.44,$59.77, and $39.04 respectively for tray container shelf, and$380.83, $25.98, and$16.9 for stackable tote shelf. The assembly time and space utilization were 8 minutes and 81.5% for tray container shelf, and 17.2 minutes and 84.4% for stackable totes. Overall, stackable tote shelves cost 55% more, but have 2.9% space utilization advantage, which can have more cost savings in an urban distribution center.by Youngjun Joh.M. Eng. in Advanced Manufacturing and Desig