Decoupled six degree-of-freedom robot manipulator

A robot manipulator having an actuator and a plurality of decoupled joints, wherein each one of said decoupled joints comprises:

• an input link having at least an input keying drive component rotatable on an input axis;
• an output link coupled to said input link and having at least an output keying drive component rotatable on an output axis;
• wherein said input and output keying drive components are constrained to rotate about one another to define an instantaneous center of rotation;
• at least an input passing drive component rotatable on said input link and coupled to said actuator for receiving rotational motion;
• and
• at least an output passing drive component rotatable on said output link and coupled to said input passing drive component for receiving said rotational motion decoupled from said one joint.

A robot manipulator having an actuator and a plurality of decoupled joints, wherein each one of said decoupled joints comprises:

• an input link having an input keying pulley;
• an output link coupled to said input link and having an output keying pulley;
• a keying cable for rotatably coupling said input keying pulley to said output keying pulley, wherein said input and output keying pulleys are constrained to rotate about one another thereby defining an instantaneous center of rotation;
• at least one input idler pulley rotatable on said input link and coupled to said actuator for receiving rotational motion;
• at least one output idler pulley rotatable on said output link;
• and
• at least one passing cable coupled to each input and output idler pulley for transmitting rotational motion of said input idler pulley and said output idler pulley decoupled from said one joint.

A multiple degree of freedom robot having a plurality of arm joints, a wrist joint coupled to one of said arm joints and having a tip, and a computer control system, said computer control system comprising:

• a user interface for receiving user commands;
• a servo controller coupled to said arm and wrist joints for reading actual positions of said arm and wrist joints;
• and
• a real-time kinematic processor coupled to said user interface and said servo controller for receiving said user commands and said actual positions of said arm and wrist joints for computing forward and inverse kinematic relationships for controlling said arm and wrist joints in accordance with said user commands and said computed relationships;
• wherein said real-time kinematic processor comprising:
• (a) means for setting a vector of tip displacements at said robot to zero,
• (b) means for computing at each joint a displacement vector corresponding to a unit motion at a current joint,
• (c) means for multiplying a displacement vector at said current joint by a transition matrix of a succeeding joint to produce a result,
• (d) means for multiplying said result by a joint axis vector of said current joint,
• (e) means for multiplying said result by said transition matrix to define a transition from a last joint to said tip,
• (f) means for setting said vector as a respective column of a jacobian matrix, and
• (g) means for multiplying a user defined vector of tip displacements by said jacobian matrix to compute corresponding joint angle displacements;
• wherein said servo controller implements said joint angle displacements.

A robot manipulator, comprising:

• an actuator base with plural actuator drives;
• a wrist with a tip;
• plural arms extending seriatim between said wrist and said actuator base;
• plural joints connected between pairs of adjacent arms;
• wherein each of said plural joints comprises means for mechanically coupling respective ones of said actuators to respective ones of said joints through intermediate ones of said joints, and wherein said means for mechanically coupling is decoupled from said intermediate joints;
• a user interface for receiving user commands;
• a servo controller coupled to said arm and wrist joints for reading actual positions of said arm and wrist joints;
• and
• a real-time kinematic processor coupled to said user interface and said servo controller for receiving said user commands and said actual positions of said arm and wrist joints for computing forward and inverse kinematic relationships for controlling said arm and wrist joints in accordance with said user commands and said computed relationships;
• wherein said real-time kinematic processor comprising:
• (a) means for setting a vector of tip displacements at said wrist to zero,
• (b) means for computing at each joint a displacement vector corresponding to a unit motion at a current joint,
• (c) means for multiplying a displacement vector at said current joint by a transition matrix of a succeeding joint to produce a result,
• (d) means for multiplying said result by a joint axis vector of said current joint,
• (e) means for multiplying said result by said transition matrix to define a transition from a last joint to said tip,
• (f) means for setting said vector as a respective column of a jacobian matrix, and
• (g) means for multiplying a user defined vector of tip displacements by said jacobian matrix to compute corresponding joint angle displacements;
• wherein said servo controller implements said joint angle displacements.

A method for manipulating a multiple degree of freedom robot having a plurality of arm joints, a wrist joint coupled to one of said arm joints and having a tip, a user interface for receiving user commands, a servo controller coupled to said arm and wrist joints for reading actual positions of said arm and wrist joints, said method comprising:

• (a) determining a set of joint coordinate displacements corresponding to a desired set of tip coordinate displacements, computing a jacobian matrix, and adding said jacobian matrix to said tip coordinate displacements to produce a corresponding joint coordinate displacement by:
• (1) setting up and computing a transition matrix defining a position and rotation transition between successive joints of said robot,
• (2) setting up vectors defining axes of rotation of each of said joint,
• (3) transforming to a desired position and an orientation change of said tip from a world reference frame to a tip reference frame;
• (4) setting a vector of tip displacements at said robot to zero, computing at each joint a displacement vector corresponding to a unit motion at a current joint by multiplying a displacement vector at said current joint by a transition matrix of a succeeding joint to produce a result, multiplying said result by a joint axis vector of said current joint, multiplying said result by said transition matrix defining a transition from a last joint to said tip, and setting said vector as a respective column of a jacobian matrix, and
• (5) multiplying a user defined vector of tip displacements by said jacobian matrix to compute corresponding joint angle displacements;
• and
• (b) implementing said joint angle displacements by said servo controller in response to step (a).

A multiple degree of freedom microsurgical robot manipulator, comprising:

• a plurality of miniaturized decoupled robot joints comprising a plurality of arm joints each having a first keying pulley constrained to rotate about a second keying pulley, thereby defining an instantaneous center of rotation to effectuate one degree of freedom movement, and a miniaturized wrist joint coupled to one of said arm joints and having a tip and three degrees of freedom;
• a plurality of miniaturized driving cables, each coupled an actuator drive at a proximal end and coupled to one of said joints at a distal end;
• and
• a computer control system coupled to each of said robot actuator drives comprising:
• (a) a servo-control sub-system for reading actual joint positions of said robot joints;
• (b) a high level sub-system for receiving user commands from a user interface and for receiving actual joint positions from said servo sub-system, wherein said high level sub-system sends said user commands and said actual joint positions to a real-time kinematic processor having a forward kinematic processor and an inverse kinematic recursive processor for computing forward and inverse kinematic relationships of said joints;
• (c) wherein said sub-system comprises means for determining a set of joint coordinate displacements corresponding to a desired set of tip coordinate displacements, means for computing a jacobian matrix, and means for adding said jacobian matrix to said tip coordinate displacements to produce a corresponding joint coordinate displacement;
• (d) wherein said servo sub-system implements said joint coordinate displacements.