SmartPowerchair: Characterization and Usability of a Pervasive System of Systems

A characterization of a pervasive system of systems (SoS) called the SmartPowerchair is presented, integrating pervasive technologies into a standard powered wheelchair (powerchair). The SmartPowerchair can be characterized as a SoS due to focusing on selection of the correct combination of independent and interoperable systems that are networked for a period of time to achieve the specific overall goal of enhancing the quality of life for people with disability. A high-level 2-D SoS model for the SmartPowerchair is developed to illustrate the different SoS lifecycle stages and levels. The results from a requirements elicitation study consisting of a survey targeting powerchair users were the input to a hierarchical task analysis defining the supported tasks of the SmartPowerchair. The system architecture of one constituent system (SmartATRS) is described as well as the results of a usability evaluation containing workload measurements. The establishment of the SmartAbility framework was the outcome of the evaluation results that concluded range of movement (ROM) was the determinant of suitable technologies for people with disability. The framework illustrates how a SoS approach can be applied to disability to recommend interaction mediums, technologies, and tasks depending on the disability, impairments, and ROM of the user. The approach, therefore, creates a “recommender system” by viewing disability type, impairments, ROM, interaction medium, technologies, and tasks as constituent systems that interact together in a SoS.