求翻译：把受试者的一只手手心向下轻放在桌面，使中指轻轻地搭在指脉换能器感受片上。让受试者保持舒适的姿势，这样不会因为除了电刺激外的其他因素晃动手臂。示意图是什么意思？

The subjects of a hand palm down light on the table, so that the middle finger to gently take to feel the piece refers to the pulse transducer. Subjects to maintain a comfortable posture, so as not shaking arm in addition to other factors outside of the electrical stimulation. Schematic diagram

The subject of one hand palm down lightly on the desktop, point to the ground gently Pulse transducer feel. Let the subject comfortable position, so that electrical stimulation in addition will not be because of other factors outside swing arm. Schematic

Receives a trying hand control downward to place the tabletop lightly, causes the middle finger to build gently in takes the pulse on the transducer feeling piece.Let the trying maintenance comfortable posture, like this cannot because rocks the arm besides the electricity stimulation other factors.

A hand Palm down the subjects of light in the desktop, middle fingers gently upon the on-chip pulse transducers. Volunteers maintain comfortable posture so that you do not because of other factors in addition to electrical stimulation of swing arm. Schematic diagram

正在翻译，请等待...