Dynamic control of a robot with its center of mass decoupled from an end effector by a redundant linkage

A zero-reaction force robot comprising:

• (a) a base;
• (b) a robot arm with a center of mass including:
• (i) an end effector linkage including an end effector which can move in n dimensions, where n is an integer, and for each dimension of operation, the end effector includes a first mass which moves in the same direction of movement as the end effector,
• (ii) a redundant linkage, including a plurality of links and joints, which connects the end effector to the base such that the robot arm has 2n degrees of freedom wherein the redundant linkage includes a second mass which can be independently moved in the same or opposite direction of movement of the first mass of the end effector, and
• (c) a dynamic controller for moving the robot arm such that the redundant linkage is repositioned in response to end effector movement to fix the position of the center of mass and prevent the coupling of reaction forces to the base.

A zero-reaction force robot comprising:

• a linkage including a plurality of vertexes;
• an end effector connected to a first vertex of said linkage;
• a base connected to a second vertex of said linkage which is opposite the vertex connected to the end effector;
• and
• a motor which varies the shape and position of the linkage in accordance with the movement of the end effector such that the center of mass of the robot remains fixed.

A method of eliminating reaction forces in a robot, said robot including a robot arm, a base, and a linkage coupling the robot arm to the base, said method comprising the steps of:

• (a) determining the desired position of the robot arm;
• (b) calculating the shape and position of the linkage which will balance the reaction forces produced by the moving robot arm so that the center of mass of the robot remains fixed;
• (c) moving the robot arm to the desired position;
• and
• (d) controlling the movement of the linkage according to the calculated values during the movement of the robot arm so that the center of mass of the robot remains fixed.

A humanoid zero-reaction force robot with a dynamically controlled center of mass comprising:

• a base link,
• a first moving joint,
• a redundant linkage including:
• a leg link,
• said first moving joint coupling the leg link to the base link,
• a body link,
• a second moving joint coupling the body link to said leg link,
• an end effector linkage including:
• a first arm link coupled to said body link by a third moving joint,
• a second arm link, including a holding tip which serves as an end effector, coupled to said first arm link by a fourth moving joint,
• wherein for each dimension of operation, the end effector linkage includes a first mass which moves in the same direction of movement as the end effector and the redundant linkage includes a second mass which can be moved in the opposite direction of movement of the first mass of the end effector,
• a head unit, connected to the body unit, including:
• a video camera, and
• a dynamic controller for moving the robot arm so that for each dimension of operation of the end effector there are at least two degrees of freedom of the robot arm to decouple the center of mass from the end effector and prevent the coupling of reaction forces to the base link.

A robot with a dynamically controlled center of mass comprising:

• (a) a base,
• (b) a robot arm including:
• (i) an end effector linkage having a clamping tip which can move in n dimensions, said clamping tip is attached to a final point at which force is to be applied, for each dimension of operation, the end effector linkage includes a first mass which moves in the same direction of movement as the end effector linkage,
• (ii) a redundant linkage, including a plurality of links and joints, which connects the end effector linkage to the base such that the robot arm has 2n degrees of freedom wherein the redundant linkage includes a second mass which can be independently moved in the same or opposite direction of movement of the first mass of the end effector linkage, and
• (c) a dynamic controller for moving the robot arm such that the robot center of mass is accelerated and decelerated to apply an impulsive force at the clamping tip.

A humanoid robot with a dynamically controlled center of mass comprising:

• a base link,
• a first moving joint,
• a redundant linkage including:
• a leg link,
• said first moving joint coupling the leg link to the base link,
• a body link,
• a second moving joint coupling the body link to said leg link,
• an end effector linkage including:
• a first arm link coupled to said body link by a third moving joint,
• a second arm link, including a clamping tip which serves as an end effector attached to a fixed point, coupled to said first arm link by a fourth moving joint,
• wherein for each dimension of operation, the end effector linkage includes a first mass which moves in the same direction of movement as the end effector and the redundant linkage includes a second mass which can be independently moved in the same or opposite direction of movement of the first mass of the end effector,
• a head unit, connected to the body unit, including:
• a video camera, and
• a dynamic controller for moving the robot arm so that for each dimension of operation of the end effector there are at least two degrees of freedom of the robot arm to decouple the center of mass from the end effector to accelerate the center of mass to impart an impulsive force at the fixed point.

A method of applying an impulsive force using a robot, said robot including a base, a robot arm including an end effector having a clamping tip and a redundant linkage, and a dynamic controller for moving the robot arm, said method comprising:

• (a) attaching the clamping tip to a fixed point at which force is to be applied,
• (b) determining the desired force to be applied at the fixed point,
• (c) calculating the required movement of the robot arm to accelerate the center of mass to impart the desired force of the fixed point, and
• (d) dynamically controlling the movement of the robot arm in accordance with the calculated required movement to accelerate the center of mass to impart an impulsive force at the fixed point.

A robot with a dynamically controlled center of mass comprising:

• (a) a base, resting on a surface,
• (b) a robot arm including:
• (i) an end effector which can move in n dimensions,
• (ii) a redundant linkage, including a plurality of links and joints, which connects the end effector to the base such that the robot arm has 2n degrees of freedom, and
• (c) a dynamic controller for moving the robot arm such that the robot center of mass is accelerated away the surface to cause the entire robot and base to jump off the surface.

A robot with a dynamically controlled center of mass comprising:

• (a) a base, resting on a first surface,
• (b) a robot arm including:
• (i) an end effector, with a clamping tip for holding an object resting on a second surface, which can move in n dimensions,
• (ii) a redundant linkage, including a plurality of links and joints, which connects the end effector to the base such that the robot arm has 2n degrees of freedom;
• and
• (c) a dynamic controller for moving the robot arm such that the robot center of mass is accelerated so that the object is lifted off the second surface.