Evaluating the Placement of Arm-Worn Devices for Recognizing Variations of Dynamic Hand Gestures

Dynamic hand gestures have become increasingly popular as touch-free input modality for interactive systems. There exists a variety of arm-worn devices for the recognition of hand gestures, which differ not only in their capabilities, but also in their positioning on users' arms. These differences in positioning might in uence how well gestures are recognized, leading to different gesture recognition accuracies. In this paper, we investigate the effect of device placement on dynamic hand gesture recognition accuracy. We consider devices being strapped to the forearm on two positions: the wrist and below the elbow. These positions represent smart watches being worn on the wrist and devices with EMG sensors for the additional detection of static hand gestures (e.g spreading the finngers) being worn right below the elbow. Our hypothesis is that wrist-worn devices will have better recognition accuracy, caused by higher acceleration values of a bigger action radius of dynamic hand gestures. We conducted a comparative study using an LG G Watch and Thalmic Lab's Myo armband, for which we recorded a total of 12960 gesture samples of eight simple dynamic gestures in three different variants with eight participants. We evaluated a potential difference in gesture recognition accuracies using different feature sets and classiers. Although recognition accuracies for wrist-worn devices seem higher, the difference is not statistically significant due to substantial variations in accuracy across participants. We thus cannot conclude that different positions of gesture recording devices on the lower arm have signicant in uence on correctly recognizing arm gestures.