Attitude stabilization control system for a legged mobile robot

A system for controlling stability of a mobile robot, comprising:

• generating means for generating an ideal behavior of the mobile robot at least with respect to a ground reaction force and/or moment acting on the mobile robot;
• model means for providing at least a first mathematical model describing relationships between a first deviation of the mobile robot's behavior, and a second deviation of the ground reaction force and/or moment without changing a state variable of the ideal behavior;
• first means for detecting an error between the state variable of the ideal behavior and the mobile robot's actual behavior;
• second means for inputting the error and determining a value of a virtual force and/or moment and supplying the value to the first mathematical model such that the error decreases;
• third means including a geometric model for inputting the ideal behavior and the first deviation and modifying the ideal behavior in response thereto, to output a modified behavior;
• and
• control means for controlling an actuator of the mobile robot to follow the modified behavior.

A system for controlling attitude stabilization of a legged mobile robot having a trunk and a plurality of legs each connected to the trunk and walking on the ground;

• comprising;
• generating means for generating a desired walking pattern of the mobile robot in such a manner that a ground reaction force and/or moment acting on the mobile robot, when the robot's leg comes into contact with the ground, is at least a desired position;
• a first mathematical model made up of an inverted pendulum having a pivot point and simulating dynamics of the mobile robot;
• a second mathematical model simulating the trunk and legs of the mobile robot such that the second model is assumed to walk on the ground in accordance with the desired walking pattern;
• first means for detecting an inclinatory error of the mobile robot relative to the second model;
• second means for determining a manipulated variable in terms of a moment in response to the detected inclinatory error and supplying the manipulated variable to the first model such that the inverted pendulum of the first model is rotated about its pivot point by an amount corresponding to the manipulated variable;
• third means for detecting positional variation of an upper portion of the inverted pendulum resulting from the rotation and correcting the motion of the second model in response to a detected positional variation;
• and
• control means for controlling joints of the mobile robot such that the mobile robot follows the motion of the second model.

A system for controlling stability of a mobile robot comprising:

• generating means for generating an ideal behavior of the mobile robot at least with respect to an ideal ground reaction force and/or moment acting on the mobile robot;
• first model means for providing a first mathematical model made up of an inverted pendulum and describing dynamics of a first deviation of the mobile robot's behavior and a second deviation of a ground reaction force and/or moment without changing a state variable of the ideal behavior;
• second model means for providing a second mathematical model describing kinematics and a posture of the mobile robot such that the second model is assumed to move on the ground;
• first means for detecting a behavior error between the model robot and the second model;
• second means for determining a value of a virtual force and/or moment in response to the detected behavior error and supplying the value to the first model such that the inverted pendulum is rotated by an amount corresponding to a determined value of the virtual force and/or moment;
• third means for changing a posture of the second model in response to a displacement of the inverted pendulum;
• and
• control means for controlling an actuator of the mobile robot such that the mobile robot follows the motion of the second model whereby the detected behavior error is decreased.