Abstract: A joint mechanism pivotably connecting first and second links respectively to be fitted on first and second body parts of a user which are connected to each other via a joint, the joint mechanism including: a first slide member connected to the first link and provided with a first slide track having an arc shape that is convex away from the joint in side view; an intermediate slide member provided with a second slide track having an arc shape that is convex away from the joint in side view, and connected to the first slide member to be slidable along the first slide track; and a second slide member connected to the intermediate slide member to be slidable along the second slide track, and connected to the second link, wherein the first and second slide tracks track have different centers of curvature.

Abstract: An ankle joint mechanism to be fitted on an ankle of a user to assist motion of a body of the user, includes: a lower leg link to be disposed along a lower leg of the user; a foot holder configured to hold a foot of the user; a plantar/dorsi flexion mechanism configured to connect the lower leg link and the foot holder to each other so as to be pivotable about a plantar/dorsi flexion axis of an ankle joint of the user; an adduction/abduction mechanism configured to connect the lower leg link and the foot holder to each other so as to be pivotable about an adduction/abduction axis of the ankle joint; and an inversion/eversion mechanism configured to connect the lower leg link and the foot holder to each other so as to be pivotable about an inversion/eversion axis of the ankle joint.