Impaired mobility is ranked as one of the most important factors that have both physical and mental impacts on patients’ life . The impacts are especially serious for the rapidly expanding elderly population in the United States, which is expected to reach 71 million, approximately 20% of the total population, by 2030 . Existing assistive tools, such as cane and walker/rollator, are helpful for such mobility-challenged individuals by providing additional support in walking. However, such tools also disrupt the users’ walking rhythm and increase their metabolic energy consumption. Wheelchairs, especially powered wheelchairs, are also used extensively among this population. Although wheelchairs are effective in transporting patients, they largely preclude the users’ lower limb muscle activities and bone load-carrying, and accelerate the musculoskeletal degeneration of the user’s lower limb .
To address the issues with existing assistive tools, the authors developed a new motorized robotic walker for mobility-challenged users. With the objective of assisting the users’ ambulation in a safe and convenient way, the robotic walker features two independently controlled wheels for the maneuverability of the robot, and two parallel bars for the user support in walking. Unlike similar robotic walkers in prior works (e.g. ), no wearable sensors are required for the user. Instead, a 3D computer vision system is used to measure the relative position of the user versus the robot, and the control commands are generated accordingly. The details of the robot design and control are presented in subsequent section.