Pedestrian Mobility Aids for the Elderly

The Walker Project


One of the most important factors in quality of life for the elderly is their ability to move about independently. Mobility impairments due to age, injury or disease cause a downward trend in their quality of life. Lack of independence and exercise can have dramatic results. Although various types of mobility aids exist in research labs and on the market, walkers are used more than any mobility aid except the cane. Our work is concerned with developing an intelligent walker to assist the elderly and increase the ease and safety of their daily travels. The benefits to the user include assistance avoiding dangerous situations (obstacles, drops, etc.) and help with navigation through cluttered environments. It is hoped that this assistance will provide the user with a feeling of safety and autonomy that will encourage them to move about more, incurring the benefits of walking and helping them to carry out the activities of daily living (ADLs). Our walker employs a shared control strategy in which both the user and the walker can provide control of the walker's heading. By dynamically shifting the balance between the degree of control provided by the walker and that provided by the user, our prototype can extend the time that a user can move independently on both a long term (as user abilities changes with age) and a short term (as user abilities change due to fatigue or medicinal cycles) basis. This point is critical because our work seeks to augment the abilities that people  possess instead of replacing them. While wheelchairs and other self-powered mobility aids are viable solutions for some people, they are not a panacea. Our work seeks to help people who can and want to walk.  There are significant economic reasons to address this problem. The world's elderly population is increasing dramatically. In the US, there are more than 34.8 million seniors over the age of 65. Furthermore, in only 30 years, this number will more than double to 70 million. In Japan, already the nation with the highest percentage of seniors on earth, it is estimated that 1 in 5 people will be seniors within 10 years. At the same time the costs of health care, including caring for the elderly, could rise from its current $1.3 trillion to over $4.0 trillion. If robotic technology can be used to enable the elderly to remain independent, significant costs could be saved and the quality of life would be improved for these people. The attainable cost savings are significant: for every single month that we delay the transition of the elderly population into nursing homes, the US economy saves over $2 billion.

We have constructed a series of prototypes of an intelligent walker and informally evaluated them with a number of users. These trials proved the feasibility of our approach, but also pointed out another critical factor in shared control with elderly users, interface. Our current work focuses on the issue of how users with decreased sensori-motor acuity can convey their intent (goals) to the walker in a way that does not increase their cognitive burden. We will study multiple techniques for communicating with the walker using groups of people with varying physical and mental abilities. The aim of these studies is to develop models of walker use by various user populations and use these models to analyze a walker user's current circumstances and predict their goal(s). This information can then be used in real-time by the walker's control system to make intelligent decisions.


Walker Team




Project Papers

Reference Documents:



This work is supported by the NSF under grant IIS-0139283.