Motivation

Problem Formulation

Implementation
System Overview
Hardware
Interaction Dialog

Discussion

Problem Formulation

Working from my motivation, the end goal of my work is to automatically choose the optimal time to:

1. suggest a person take a walk based on internal user state (affect or at least valance) and the way in which to present this suggestion.

2. gain information on how exercise, or lack thereof, effects the users emotional state throughout the day.      

Teasing out some of the more fundamental components of this problem two important questions become apparent:

1. How to detect affect change? How to illicit both valence and arousal?

2. How to understand when a person is engaged in physical activity or not?

These problems are addressed by my implementation. The theory behind my motivation includes:

1. Liu & Picard - Using heart rate for understanding affect.

2. Ho & Intille - Using accelerometers to understand transitions and thus activity state (sitting, walking, standing)

3. Isen et al 87 on Affect and Creativity - Use a word/picture association to measure valence

4. R. McCraty et al - The effects of emotion on heart rate, specifically the fact that some emotional arousal increases heart rate.

5. Singh Systems & Control Encyclopedia - Understand the electrical characteristics of the heart

6. Russel (1980) - His work on the circumplex model of emotions to validate the use of heart rate and word association to measure arousal and valence.

7. Implicit Association Test - Method for word association