Exploring Acceptable Weight Criteria for Finger-Worn Haptic Device Design

The development of finger-worn haptic devices requires careful consideration of weight-related design trade-offs. Increased functionality commonly results in additional device weight, potentially burdening the wearer and impairing finger dexterity. Despite the importance of weight in design considerations, the field lacks criteria for acceptable device weight. This study addresses this gap by exploring weight criteria for continuous wear. We posit that for such devices to be adopted, their weight must not hinder daily activities when the device is not providing haptic feedback. In experiments, we investigated how device weight affected performance during common office tasks, specifically pointing and typing. Participants wore a mockup of a finger-worn haptic device and completed tasks as quickly and accurately as possible. We manipulated the weight (0, 20, 40, and 60 g) and placement of the device (proximal and distal). Across tasks, we found that adding up to 60 g to the index finger did not degrade task performance, while subjective user load increased under some conditions. These findings suggest that in scenarios where office task performance is critical, devices weighing up to 60 g are acceptable regardless of their placement on the finger.