Design, Fabrication, and Testing of Assistive Mobility Solutions for Health Care Facilities

Abstract

The movement of people, medication, and equipment in health care is a crucial part of the workflow, however, it is also an area that causes significant physical strain to the workers. This thesis proposes a design which is used to retrofit existing medical beds and carts with motorized modules that reduce the amount of force required for a worker to move equipment within hospitals and long-term care homes. The unique design makes use of mechatronic design principals to offer reliable and effective solutions to mobility problems in health care environments. Though available motorized beds and carts exist, they tend to be expensive as they are integrated in the bed and cart designs, thus requiring new equipment to be purchased. This is not always possible as it requires a large initial investment, while also introducing a foreign piece of equipment that workers must learn to use. The designed solution solves this by considering the existing design of medical equipment and adding technology to its frame to vastly reduce the costs. Adding onto the established medical designs allows for the electromechanical assembly to be the focus of the retrofit, coupling its additional functionality to familiar equipment. In this thesis, modules for improving beds and carts are designed, fabricated, and tested. The mechatronic design of the bed establishes a set of components and parameters that are successful in allowing for locomotion in indoor environments without the need for significant muscle exertion. The thesis scope details the mechanical design and electric and pneumatic component selection of the bed for a platform created to allow for manual, assistive, and autonomous controls. Using the experience and observations made while designing the bed platform, a more general assistive cart design is created. The cart offers a streamlined module that offers longitudinal torque assistance and can be paired with a wider range of medical equipment. An assistive handle allows for a seamless control experience on the assistive cart, wherein the assistive torque provided by the motorized module can be scaled by sensing the force exerted on the handle. This is observed to reduce the force needed to push a cart, and significantly decreases the effort needed to maneuver a heavy cart. The cart is also proven to be effective in its intended environment through limited prototype use in Grand River Hospital. An alternative cart is also designed, which can couple and detach from carts. This solution allows for a large fleet of similar carts to be powered using one product, rather than requiring a module for each cart.