Fig. S5.

Examples illustrating the difference in vibration acceleration magnitude at the skin during hand gestures with and without touch contact. (A) Vibration acceleration magnitude was nearly three orders of magnitude smaller in the noncontact condition (∼$4\times {10}^{-3}$ m/s²) than in the contact condition (between 0.6 and 3.9 m/s²). (B) The magnitude of vibration in the noncontact condition remained small (∼$4\times {10}^{-3}$ m/s²) when averaged between all measured gestures in the dataset. The noncontact data were extracted from our original data recordings (sensor configuration 30W, all gestures). They were obtained by deleting a segment of time during each trial that corresponded to the touch contact phase and its immediate aftereffects. Because touch elicited vibrations decayed rapidly, the deleted segments averaged less than 100 ms in duration.