A Pilot Investigation of Human Preference for Robot Arm Visual Form

First impressions matter, and a robot's appearance has a significant impact on a user's perception of it, as well as their decision whether to use it. At the same time, there is a knowledge gap on non-anthropomorphic robot design form's effects on human perceptions and therefore interactions with non-humanoid robots. In this paper, we begin to evaluate the effects of two specific non-anthropomorphic form conditions: robot arm link concavity and roundness. After systematically varying robot arm stimulus models' morphological characteristics, we conducted an online survey-based within-subjects pilot study (N = 10) to gather participant ratings of attributes for each arm. We found that the perceived safety was significantly higher for the most rounded link compared to the intermediately rounded link. Participant free-response feedback can also support future hypothesis generation, such as a possibility that convex forms may seem more humanlike. This work contributes a starting point for future exploration in the realm of non-anthropomorphic robot design.