Force sensor and robot equipped with force sensor

A device comprising:

• a member;
• and
• a force sensor configured to be attached to the member, the force sensor comprising:
• a base unit;
• a displacement unit configured to be displaced with respect to said base unit by receiving an external force;
• a first displacement sensor pair including two sets of sensors that detect a relative displacement between said base unit and said displacement unit in a first direction;
• and
• a second displacement sensor pair including two sets of sensors that detect a relative displacement between said base unit and said displacement unit in a second direction intersecting the first direction,
• wherein among four quadrants of the force sensor, divided by two straight lines along each of the first direction and the second direction, the straight lines passing through a midpoint of the two sets of sensors composing said first displacement sensor pair, the two sets of sensors composing said second displacement sensor pair are respectively disposed in two quadrants in which the two sets of sensors composing said first displacement sensor pair are respectively disposed, and
• wherein the two sets of sensors composing said first displacement sensor pair are separated from each other by a predetermined distance in each of the first direction and the second direction, and the two sets of sensors composing said second displacement sensor pair are separated from each other by a predetermined distance in each of the first direction and the second direction.