Tipover Stability Measure for Pedestrian Mobility Aids for the Elderly and Its Representation for User’s Monitoring

One way that reduces the incidence of the accidents associated with mobility aids (also called walker or rollator) is to give the information of the stability margin to the user before a tumble of such devices occurs. From this point of view, this paper presents a tipover stability measure that makes use of the concept of the manipulability measure for robot manipulators and its representation manner for user’s monitoring. We first briefly introduce the manipulability measure for the two-link planar manipulator and indicate that there is a resemblance between tipover stability and the configuration of the two-link planar manipulator. It is described why the manipulability measure can be used for expressing a current stability measure, and the formulation to obtain the presented tipover stability measure is then carried out. Subsequently, a number of examples are given and discussed to compare with other stability measures. A representation method of the tipover stability measure is finally presented. Several examples show that such a representation method is effective to let the user know a current stability level as well as whether or not the user can push the mobility aid in a certain direction without disturbing stability.