Adam Hoover, Eric Muth Electrical & Computer Engineering Dept Psychology Dept Clemson University

1. Adam Hoover, Eric MuthElectrical & Computer Engineering DeptPsychology DeptClemson University The Bite Counter

2. Outline 1. The obesity problem 2. Our concept 3. How it works (and how well) 4. Manufacturing 5. Pilot study

3. The Obesity Problem More than 27% of U.S. adults, ages 20-74, are obese U.S Department of Health and Human Services, 2007 Worldwide, over 1 billion adults (ages 15+) are overweight or obese World Health Organization, 2009 Related health risks include cardiovascular disease, diabetes, cancer, and hypertension $117 billion annualy to treat obesity-related issues in U.S. Kelly, “Obesity: Health and Medical Issues Today”, 2000

4. New tools needed • International Obesity Society: 10,000 researchers • Obesity Society (U.S.): 2,500 researchers • Joint NSF/NIH Workshop • (Ershow et al. 2007) “Engineering Approaches to Energy Balance and Obesity: Opportunitites for Novel Collaborations and Research” • Journal of the American Dietetic Association • (Thompson et al. 2010) “Need for Technological Innovation in Dietary Assessment” • (McCabe-Sellers et al. 2010) “Advancing the Art and Science of Dietary Assessment through Technology”

5. Balancing Energy Output and Intake exercise diet healthy weight X + Y = weight loss/gain Tools can assist counting input and output

6. Tools: Measuring Energy Output Odometers measure time, distance, velocity Commonly used in exercise Provide rough estimate of calories burned

7. Tools: Pedometer A pedometer is worn on the waist Can be worn all day, used anywhere Measures steps, e.g. during exercise

8. Tools: Measuring Energy Intake Manually counting calories Pre-packaged foods and serving sizes Calorie or food diary None of these are easy to use consistently over long periods of time

9. Our concept: Bite counter Can vibrate to tell you when to stop eating Worn like a watch Automatically tracks how many bites of food have been taken

10. How do bites relate to calories? Weight loss does not happen in a single meal (or bite); it takes weeks to months of consistently consuming less food 1 pound per week is a common guideline (American Heart Association) People are bad at counting calories Undercounting 200-500 calories per day (Champagne et. al. 2002) Calories are not as accurate as we like to believe Frozen dinners 8% under, fast food 18% under (Urban et. al. 2010) People tend to eat the same foods week-to-week Reduce the bites … reduce the calories

11. Does bite size matter? How many bites do you eat in a meal? 10-75, based upon our testing Bite count goals will be customized to the individual, and will be based upon monitoring the individual for a week Example: After a week of monitoring, we determine your average lunch bite count is 38; we recommend reducing that to 32 At daily and weekly intervals, goals could be given to smooth out spikes in eating behavior Example: Upon reaching dinner, the device indicates you have already consumed 183 bites today; a small dinner is recommended

12. Advantages of our device • Objective • No guessing, or thinking back over a day to total consumption • Automated • You can be doing other things (talking with friends, working, watching TV, etc.); the device does all the counting • Real-time feedback • The device can give you cues to stop eating BEFORE you have consumed more than you intended

13. How it works The wrist undergoes a characteristic roll motion during the taking of a bite of food Biologically, this can be related to the necessary orientations for (1) picking food up, and (2) placing food into the mouth

14. How it works Tracking the wrist roll motion, we have identified a 3-event pattern that corresponds to the taking of a bite of food

15. Demo

16. How well does it work? Experiment #1: Waffles 51 subjects, 139 meals, same food (waffles), same utensil 94% bites correctly detected 80% positive predictive value Experiment #2: Any foods, in lab 47 subjects, 49 meals, any food (and drink), any utensil 88% bites correctly detected 76% positive predictive value Talking, other actions during 67% of bites

17. Experiment #3: Two weeks • Test relationship between bites and calories • 83 subjects wore for 2 weeks • 3246 meals • 76% have correlation > 0.4 • 69% between 0.4 and 0.7 Correlation: 0.4 Correlation: 0.7

18. Experiment #4: Cafeteria Harcombe Dining Hall; seats 800 people Instrumented dining table

19. How do we build it?

20. Embedded System Design Lab model Watch model

21. Breadboarding and parts selection I/O (buttons, speaker, vibratory motor, USB port) gyroscope LCD charger processor battery, holder

22. Processor dev board JTAG-USB development board

23. LCD surfboard and custom breakout board

24. Gyroscope typically follow “application circuit” from manual

25. Battery What can you wear? How long will it run?

26. Design stages Breadboard Circuit diagrams

27. Design stages Circuit diagrams Printed circuit board (PCB) & manufacturing EEEA, Inc

28. Design stages PCB Molding and case production Center Line Technology

29. Design stages PCB, case Assembly

30. Bite counter PCB gyroscope speaker charger USB port LCD battery processor JTAG buttons USB-RS232 bridge