Gaming Components Affect Locomotion, Balance, and Quality of Life
Millions of people walk and handle household tasks without giving any thought to balance or the use of their legs in these activities. Life is entirely different for those with impaired balance resulting from neurotrauma, such as stroke or traumatic brain injury or those adjusting to life with a prosthetic lower limb. Robotics research at Notre Dame is being applied to improve the quality of life for potentially tens of thousands of people whose ability to walk or maintain balance has been diminished.
James Schmiedeler, associate professor of aerospace and mechanical engineering, and the Locomotion and Biomechanics Lab at ND study a variety of topics, many related to the theme of understanding human balance and gait. Researchers study human balance and locomotion then apply what is learned to the study of robotics; in turn, the knowledge that is gained through the study of robotics is applied to the understanding of human walking and balance.
Balance is a foundational skill that plays a significant role in daily life. Regaining balance can reduce the risk of falling and the complications resulting from fall injuries. Restoring balance affects quality of life, enabling the individual to safely resume activities like preparing meals or getting in and out of a car easily. The group has developed a tool called the WeHab system that can be used in hospitals and clinics to assist in balance rehabilitation. The device uses relatively inexpensive gaming components and a tablet or laptop, coupled with visual feedback to help patients regain balance capabilities. Local hospitals are using the WeHab system and in future the software is expected to be available to anyone open source, extending the range of potential users.
In recent years, the number of individuals who have experienced the loss of a lower limb has increased, largely as a result of disease or military service. Not only is balance an issue for this group of individuals, but a correctly chosen and properly aligned prosthesis is critical for comfort and support. An optimal fit depends upon the skill of the individual prosthetist; by providing a tool to improve the ability of any prosthetist to correctly select components and align the prosthesis, a much greater number of individuals can benefit from a well-chosen and well-fitted device and an improved quality of life. The robotics team at ND has intensively studied human walking, then taken the control strategies used in creating a biped robot and successfully translated them into a highly accurate mathematical model capable of predicting human gait.
The predictive model is inspired by studies of the motion of the foot and ankle, and it predicts the individual’s step length and power when supplied with the person’s height, weight, and walking speed. For the user of a prosthesis, this means that a doctor or prosthetist can adjust the device to deliberately attain an expected gait for the user — adjustments and alignments can be more accurate and more easily modified, ultimately providing a more comfortable fit. Gait adjustments are expected: as children grow or adults age, the gait will need to change; the optimal pace may be increased to encourage strength building or reduced to accommodate other health issues that occur. Proper comfort and strength means the user is more likely to use the device and walk further and more often, a simple increase in exercise that can enhance cardiovascular health.
The wide array of projects underway in the Locomotion and Biomechanics Lab illustrates a balance between theory and experimentation; work in the robotics lab is neither purely theoretical nor purely experimental. The theories are developed in order to enable exciting experiments, and the experiments are grounded in solid theory; in turn people can benefit significantly from application of the tangible project outcomes.