Signal Processing for a Wheelchair Pressure Relief Monitoring System

Pressure ulcers are a major problem for wheelchair users [1]. Pressure ulcer prevention typically involves the use of a pressure-distributing wheelchair cushion and/or by periodic pressure relief (PR) or weight shift activities performed by the subject [2]. In order to gauge the efficacy of these PRs in preventing pressure ulcers, it is necessary to compile a record of their nature and frequency under realistic in-situ conditions. Additionally, it is necessary that this record be accomplished by a non-intrusive objective measurement system. This insures that the subject’s behavior is not influenced by the data collection and that PRs that are both volitional and those that are incidental to daily activities are properly recorded.