Grant: Discovery Grants Program - Individual

The relationship between human mobility and quality of life has been widely studied. The loss of mobility is not solely associated with physical disabilities but has a significant effect on all aspects of life, including mental and social aspects. Mobility issues are a substantial challenge for the aging population due to their weakening musculoskeletal systems and vulnerability to instability and falling. With reference to the 2016 census, there are 5,935,635 Canadian seniors (i.e. 65 years of age or older). This demographic is expected to further increase as life expectancy rises. Maintaining and enhancing mobility for seniors is of critical importance for society as a whole and must be addressed with viable solutions.    Researchers have recently developed mobility assistive devices to enhance people's ability to walk. Among these innovations is the Walking Assist Exoskeleton (WAE), which is a wearable robotic device that interacts with the user's body to assist with physical activities. Primarily driven by electrical motors and rigid links, it has the ability to physically assist the user. However, this solution is not without limitations. Limited range of motion, discomfort, bulkiness, limited operation time and excessive cost are among its many drawbacks. Recent alternative solutions have been emerging, notably passively-driven WAE. While these mechanical systems display the potential of creating simple and cost-effective mechanical exoskeletons, they still face challenges related to range of motion, adaptability, as well as synchronization of gait energy-storing-and-releasing mechanisms.    This research program proposes the development of self-sufficient sex-specific WAEs that employ conforming mechanical joints, quasi-passive actuators and gait sensors. These system characteristics yield to a compliant physical interface with the user that enhances their mobility without impeding natural joint kinematics. Without relying on an external power source, the system would harvest the kinetic and potential energy of human gait and return it as a mechanical contribution. System performance and adaptability are enhanced by actively controlling the passive behaviour of the actuators and gait energy-storing-and-releasing mechanisms throughout the gait cycle.    For the proposed WAEs, compliant passive actuators are explored, namely, the Tubular Soft Composite and Twisted Coiled-Polymer. While both types of actuators would face challenges pertaining to the power source necessary for their functioning within a self-sufficient system such as a WAE, they are both developed with the ability to actively control the passive behaviour of the mechanism, providing the system with the power to adapt.    Unlike current technologically advanced WAEs, the proposed exoskeleton will be affordable, comfortable and functional, allowing for the restoration or enhancement of an elderly user's mobility and reduction of metabolic cost during locomotion.