Lead-through teach handle assembly and method of teaching a robot assembly

A robot assembly comprising:

• at least one robot arm including at least one mounting site;
• a mounting mechanism mounted to said mounting site on said robot arm;
• a handle supported by said mounting mechanism, said handle adapted to provide at least one surface for a user to grasp such that the user can input a force required to move said robot arm along a desired operating path;
• said assembly characterized by a first joint member mounted to said handle and a second joint member mounted to said mounting mechanism, said first and second joint members coupled together to interconnect said handle and said mounting mechanism and to accommodate orientation changes of said handle relative to said mounting mechanism resulting from translational and rotational movement of said robot arm as the user is teaching the desired operating path.

A method of teaching a robot assembly a desired operating path within a workspace wherein the robot assembly includes at least one robot arm, a motor, and a tool having a tool center point and an orientation, said method comprising the steps of:

• applying an external force at the tool to impart movement on the robot arm such that the arm of the robot assembly moves along the desired operating path wherein the imparted movement is at least one of translational movement and rotational movement;
• estimating the external force applied at the tool;
• generating motion commands in response to the external force to supplement the movement imparted on the tool in a direction of the estimated external force thereby assisting a user in moving the robot arm;
• and
• selecting at least one teach operating mode depending upon the desired operating path to be taught wherein the selected teach operating mode distinguishes between (i) a translational operating mode which defines a first three-degrees of freedom of movement and limits the movement imparted on the tool to translational movement such that a first spacial relationship defined between the orientation of the tool and the workspace is maintained during teaching, and (ii) a rotational operating mode which defines a second three-degrees of freedom of movement and limits the movement imparted on the tool to rotational movement such that a second spacial relationship defined between the tool center point and the workspace is maintained during teaching.