Abstract
Perceiving the weight of a lifted object from visual displays of the lifting person is a non-trivial task. Runeson and Frykholm (1981), who worked with biological motion point-light displays, attributed the ability to estimate the weight of a lifted box to what they called the Kinematic Specification of Dynamics. The KSD assumes that dynamics are inferred from observed kinematic patterns by means of an internal model of the relations between body shape and body kinematics. Using MoSh, that is, Motion and Shape Capture from Sparse Markers (Loper, Mahmood, & Black, 2014) we created animated, life-like human avatars from surface motion capture data of performers lifting light and heavy boxes. For some of our stimuli, we then combined the body shape of one lifter with the kinematics of another to create hybrid lifters. In the consistent condition, stimuli were generated using the shape and movement from the same performer. In the low- and high- inconsistency conditions, the shape and movements of the stimuli were taken from different performers; however, in the former, the shape and motion were from different performers with similar body masses, and in the latter, shape was matched with motion from individuals with dissimilar body masses. Participants estimated the perceived weight of the lifted box. Results showed that participants could discriminate between box weights, although they slightly overestimated their real weight. However, we did not find the expected dependency of internal consistency. Further studies will examine the degree to which larger inconsistencies are detectable, and in which domains internal consistency matters.
Meeting abstract presented at VSS 2016