Electrocardiogram Measurement and Emotion Estimation of Working Dogs

Physiological measurements of dogs' emotional states during human-animal interactions are essential for understanding the underlying biological relationship. Heart rate measured by electrocardiogram (ECG) can be used for the physiological measurement of emotional state. Soft disposable electrodes, which can be purchased commercially and reduce the risk of an injury on hitting objects, are used to measure the heart rate during working dogs' exercise. However, the heart rate measurements using soft disposable electrodes in M-X lead layout are unstable due to the detachment of electrodes during intensive movement. In addition, the collection of accurately labeled ECG data, which reflects the emotion of the working dog during exercise, is a key issue to conduct reliable estimation and visualization of the working dog's emotional states. In this paper, we propose an innerwear that fixes soft disposable electrodes in M-X lead layout on a dog's body for measuring the heart rates of exercising dogs, even during intense movement. We experimentally tested the proposed method using seven dogs. Our proposed system reduced the time required to attach soft disposable electrodes by more than two-thirds and enabled the measurement of >97% of the heartbeats in exercising dogs. We also proposed a method for collecting ECG data with reliable positive/negative emotional labels of search and rescue (SAR) dogs. A combination of the collected data with the emotion estimation algorithm proposed in previous studies estimated SAR dogs' positive/negative emotions at 97.9% accuracy. The transition of the two SAR dogs' emotions during drills was visualized using the collected data.