Patent ID: 6962220

Claim:
A leg joint assist device for generating an auxiliary driving force on a specific joint of a legged mobile robot in parallel with a driving force of a joint actuator driving the specific joint, the robot comprising a plurality of legs, extending from a body, configured by connecting a plurality of link members sequentially from a body side through the plurality of joints, wherein at least one joint amongst a plurality of the joints of each of a plurality of the legs is defined as the specific joint in the legged mobile robot, the leg joint assist device comprising: spring means, provided to be able to transmit a relative displacement motion of a pair of the link members connected by the specific joint, the relative displacement motion being caused by actuation of the specific joint, for generating the auxiliary driving force while storing elastic energy in synchronization with the relative displacement motion in a state where transmission of the relative displacement motion is continued, and for restoring a state where the elastic energy is released in a state where transmission of the relative displacement motion is discontinued; motion transmission continuation/discontinuation means for continuing and discontinuing transmission of the relative displacement motion of the pair of link members to the spring means; and control means for controlling continuation/discontinuation of transmission of the relative displacement motion to the spring means by the motion transmission continuation/discontinuation means, depending on a state of motion of each of the legs.