Wearable device with muscle activity detector

1. A wearable device that is attached to one upper limb from among left and right upper limbs of a user, the wearable device comprising:

a display configured to display an image;

a muscle activity detector coming in contact with the one upper limb, the muscle activity detector configured to detect muscle activity of the one upper limb; and

a controller configured to:

detect a bodily motion of the one upper limb based on the detected muscle activity,

cause the display to perform a predetermined display operation in response to the bodily motion

calculate an amount of displacement of a body accompanying the bodily motion, and

as the predetermined display operation, vary display contents of the display based on the amount of displacement,

detect a predetermined intermediate state in between a state in which the first motion is performed and a state in which the second motion is performed,

start calculating the amount of displacement when a state of the body reaches the intermediate state during the bodily motion with the intermediate state serving as a reference state, amount of displacement of the body from the reference state is calculated as the amount of displacement,

detect a motion of fingers as the bodily motion,

detect, as the intermediate state, a state in between a state in which fingers are completely bent and a state in which fingers are completely extended, and

calculate, as the amount of displacement, amount of change by which amount of bending of the fingers changes with respect to amount of bending of fingers in the intermediate state.

2. A wearable device that is attached to one upper limb from among left and right upper limbs of a user, the wearable device comprising:

a display configured to display an image;

a muscle activity detector coming in contact with the one upper limb, the muscle activity detector configured to detect muscle activity of the one upper limb; and

a controller configured to detect a bodily motion of the one upper limb based on the detected muscle activity, and configured to cause the display to perform a predetermined display operation in response to the bodily motion, wherein

the display has a first display area placed along an outer side of the forearm and has a second display area placed along an inner side of the forearm,

the display is placed along a forearm of the one upper limb,

the controller is configured to detect a rotation motion of the forearm of the one upper limb as the bodily motion,

the controller is configured to detect a pronation motion and a supination motion as the rotation motion,

when the pronation motion is detected, the controller is configured to ensure that the predetermined image is displayed in the first display area as the predetermined display operation, and

when the supination motion is detected, the controller is configured to ensure that the predetermined image is displayed in the second display area as the predetermined display operation.

3. The wearable device according to claim 2 , wherein

the display further has a third display area that

is placed along lateral of the arm of the one upper limb, lateral corresponding to side of pollex of the upper limb, and

is placed in between the first display area and the second display area,

the controller is configured to calculate amount of rotation of forearm during the rotation motion, and

when the amount of rotation is smaller than a predetermined value, the controller is configured to display the predetermined image in the third display area in place of the first display area or the second display area.

4. The wearable device according to claim 3 , wherein

in case of displaying the predetermined image in the third display area, the controller is configured to display a plurality of display image candidates in the third display area, and

in response to the detected bodily motion, the controller is configured to make one of the plurality of display image candidates selectable.

5. The wearable device according to claim 4 , wherein, in a state in which one of the plurality of display image candidates is selected, upon detecting the rotation motion, the display is configured to display the selected display image candidate in the first display area or the second display area as the predetermined display operation.