Up, up, and away!

Is it a bird? Is it a plane? No, it is ... - well it's not Superman either. But who knows, maybe one day he'll be using this tool as well to question his work behavior. So how would he be doing is? By reacting to what the colors of the lamp attached to his desktop tell him about his heart rate variability (HRV). Ok as if Superman would be working on a desk. A flying desk maybe... Nevertheless, the HRV metric that once was thought to be noise in heart rate monitoring, is nowadays known to provide rich information on the physical and mental state of individuals. In this manner it is for example used to indicate when an athlete has been overtraining, when mental workload of a system operator is high, or when an individual is feeling stressed. To summarize and generalize a bit, HRV can be used to inform about how healthy the body reacts to the demands of a situation.

The system visible in these images continuously collects heart rate data from a Zephyr HxM Smart chest strap, transmits the data on RR-Intervals through an interface using the BLED112 USB dongle to the PC, which runs a Java application that computes the HRV-feature called SDNN on the data of the past 5 minutes. The HRV metric is then sent to a Philips Hue lamp which maps high HRV levels (good) to a blue color, and low HRV levels (bad) to a red color, to indicate, that maybe a break might be in order.

Using this device a user could learn about situations and times during, for example a work day, that caused him to experience strong physical or mental demands. Using it throughout this week, I for example learned that my usual mid-day nap requirement is brightly visualized by a flaring red lamp. So I think, this should give me permission to sleep more when sleep is due. A word of warning: this advice might not be transferrable to any workplace. Please consult your supervisor for potential side-effects.

If you are interested in trying it out yourself, feel free to contact me for a copy of the code.

Contributors to this project:

• Michael T. Knierim

References related to this project:

• Al Osman et al. (2014) – U-biofeedback: a multimedia-based reference model for ubiquitous biofeedback systems
• Garde et al. (2002) – Effects of mental and physical demands on heart rate variability during computer work
• Snyder et al. (2015) – MoodLight: Exploring Personal and Social Implications of Ambient Display of Biosensor Data
• Züger et al. (2017) – Reducing Interruptions at Work: A Large-Scale Field Study of FlowLight