Figure 9.

Experimental setup and protocols. Dataset was recorded under three sessions, and the datasets from the first two sessions (day 1 and day 2) was released for training purposes. The test data released later to competitors was obtained in the third session. (A) During a session of the experiment, subjects were seated in a comfortable chair in front of a 24-inch LCD monitor screen. (B) Three designated objects (cup, ball, and card) were placed on the screen, and a visual cue (a flashing green circle around the targeted object) indicated what grasping motion the subject should imagine. (C) A single trial comprised three continuous stages, which posed a designated task to the subjects. These experimental stages were rest, preparation, and performance of movement imagery. A single trial lasting 10 s consisted of three sub-stages, which were 3, 3, and 4 s in duration, respectively. The subject performed motor imagery during the 4 s stage after the visual cue was provided.