The following questionnaire was given to each subject of the APEE study.

The results are shown below.

Some of their comments are as follows.

(1) The eyeglasses-attached sensor is compact and good.

(2) There is some actuator noise, but the noise may let a user know the pedal ON/OFF timing.

(3) The pedal-releasing operation is more difficult than the pedal-depressing operation.

(4) The actuator follows the head movement more naturally than I thought.

(5) Use of horizontal movement of the head may be an option.

(6) I think that the more you practice, the more easily you can use the device.