Design and analysis of the SmartWalker : a mobility aid for the elderly

In the near future, the baby boomer population will cause a growth in the number of people entering nursing homes. Currently, if people wish to stay out of a nursing home, they must hire a personal aid to take care of daily tasks. A more cost-effective method could be to employ a robotic aid to help with these chores. One such aid is the SmartWalker, a robotic device that would provide health-monitoring sensors, physical support, and help in mobility to the elderly. The focus of this thesis is the design and analysis of the SmartWalker hardware. The design tools necessary to prevent the SmartWalker from slipping, tipping over, and experiencing brake failure are presented. Furthermore, a study of the omnidirectional platform used on the SmartWalker is performed for uneven terrain. It is shown that all of the wheels of the platform touch the ground at the same time. A simulation of a split caster mobility module, the main component of the omnidirectional platform, traversing a bump is also done. This proves that the control algorithms designed for a perfectly flat floor will suffice on an uneven floor. In addition, this thesis discusses the mechanical design that is necessary to build the SmartWalker. The mechanical design focuses on the split caster mobility modules, the slip rings, the frame, and the tradeoffs between strength and weight. Thesis Supervisor: Dr. Steven Dubowsky Title: Professor of Mechanical Engineering ACKNOWLEDGMENTS First and foremost, I would like to thank my parents for their support. In addition I would like to thank Professor Steven Dubowsky for his guidance and the Home Health Care Consortium for their financial support of the project. Thanks also to the members of FSRL during the past twenty months, especially Adam Skwersky and Haoyong Yu for their help with debugging the walker.

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