A Novel Earphone Type Sensor for Measuring Mealtime: Consideration of the Method to Distinguish between Running and Meals

Abstract

Abstract:In this study, we describe a technique for estimating meal times using an earphone-type wearable sensor. A small optical sensor composed of a light-emitting diode and phototransistor is inserted into the ear hole of a user and estimates the meal times of the user from the time variations in the amount of light received. This is achieved by emitting light toward the inside of the ear canal and receiving light reflected back from the ear canal. This proposed technique allowed "meals" to be differentiated from having conversations, sneezing, walking, ascending and descending stairs, operating a computer, and using a smartphone. Conventional devices worn on the head of users and that measure food intake can vibrate during running as the body is jolted more violently than during walking; this can result in the misidentification of running as eating by these devices. To solve this problem, we used two of our sensors simultaneously: one in the left ear and one in the right ear. This was based on our finding that measurements from the left and right ear canals have a strong correlation during running but no correlation during eating. This allows running and eating to be distinguished based on correlation coefficients, which can reduce misidentification. Moreover, by using an optical sensor composed of a semiconductor, a small and lightweight device can be created. This measurement technique can also measure body motion associated with running, and the data obtained from the optical sensor inserted into the ear can be used to support a healthy lifestyle regarding both eating and exercise.Keywords: wearable device; ear canal; meal time estimation; body vibration on running; dietary support Background and ObjectiveThe use of wearable devices is growing in popularity in the field of healthcare [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16]. Wristwatch-type wearable devices are particularly widespread and estimate the amount of exercise by measuring body temperature and heart rate, thereby supporting a user's diet by presenting these estimates. In dietary support, the use of measured results for meals is just as important as support that uses measured results for the amount of exercise. Calorie control is the main form of support for meals; however, support using meal time management has recently received growing attention. Irregular meal times and eating before bedtime have been found to be some of the factors that promote the onset and progression of lifestyle-related diseases [17]. However, support for ordinary individuals

A basic study for estimation of occlusal force using an ear wearable sensor

“…Then we experimentally determined characteristics of the sensor (see Sections 2.4. and 3.1). As regards measurement of ear canal movement, we used an ear wearable sensor that we have worked on …”

“…We have been engaged in development of wearable devices that can easily measure occlusal force and chewing ability at home or in hospital, and in research on health management using thus measured results. In our previous research, we aimed mainly at health care and monitoring and focused on distinctive variation patterns that appear only in eating (chewing); in so doing, we implemented mealtime measurements using an ear wearable sensor . In that research, we evaluated accuracy of meal duration by means of average overlap ratio.…”

Earable RCC: Development of an Earphone-Type Reliable Chewing-Count Measurement Device

“…In our previous research, we focused on the distinctive pattern of variation associated with consuming meals (chewing), mainly with the aim of healthcare monitoring. We developed an earphone-type sensor (wearable device) and demonstrated its effectiveness in obtaining robust measurements during meals [15]. …”

Earable POCER: Development of a Point-of-Care Ear Sensor for Respiratory Rate Measurement

“…The earable POCER, automatically measure respiration frequency through the attachment of an earphone-sensor (hereafter referred to as an “ear sensor”) to the right ear or left ear of the measured subject and displays the results on a tablet terminal. Thus far, using an ear sensor, we have been successful in researching and developing devices for measuring meal times, a measuring device for the number of chewing times, and hands-free interfaces based on results from measuring tongue activity [ 14 , 15 , 16 , 17 , 18 , 19 , 20 ]. For this sensor technology for the earable POCER, we applied the ear sensor technology that we developed previously.…”