A Ballistographic Approach for Continuous and Non-Obtrusive Monitoring of Movement in Neonates.

Continuously monitoring body movement in preterm infants can have important clinical applications since changes in movement-patterns can be a significant marker for clinical deteriorations including the onset of sepsis, seizures, and apneas. This paper proposes a system and method to monitor body movement of preterm infants in a clinical environment using ballistography. The ballistographic signal (BSG) is acquired using a thin and a film-like sensor that is placed underneath an infant. Manual annotations based on video-recordings served as a reference standard for identifying movement. We investigated the performance of multiple features, constructed from the BSG waveform, to discriminate movement from no movement based on data acquired from 10 preterm infants. Since routine cardiorespiratory monitoring is prone to movement artifacts, we also compared the application of these features on the simultaneously acquired cardiorespiratory waveforms, i.e., the electrocardiogram, the chest impedance, and the photoplethysmogram. The BSG-based-features consistently outperformed those based on the routinely acquired cardiorespiratory waveforms. The best performing BSG-based feature-the signal instability index-had a mean (standard deviation) effect size of 0.90 (0.06), as measured by the area under the receiver operating curve. The proposed system for monitoring body movement is robust to noise, non-obtrusive, and has high performance in clinical settings.

Improving posture and sitting behavior through tactile and visual feedback in a sedentary environment.

This paper presents the concept Backtive: an interactive office chair with an accompanying mobile application to provide both tactile and visual feedback for the user to correct his posture and make him more aware of the sitting behavior throughout the day. The concept aims to make people unintentionally and more voluntarily aware of their sitting behavior while not interrupting their daily tasks. The concept is developed through a user centered design approach and by building a prototype to test feasibility as well as evaluating the concept. An evaluation with four persons received positive results with regard to credibility and expectancy of Backtive for posture improvement. Participants also expect that Backtive would be easy in use and are likely to integrate the system in their daily activities.