Error recovery methods for controlling robotic systems

A method of controlling a dispensing system having a robot for application of a material to a workpiece wherein the dispensing system prevents any gaps or overlaps in the material on the workpiece, said method comprising the steps of:

• moving the robot along a motion segment at an operational speed between a first position and a second position;
• applying a first portion of the material to the workpiece as the robot moves along the motion segment;
• discontinuing the application of the first portion of the material in response to an error that occurs during the application of the first portion;
• establishing a re-application position for the material along the motion segment in response to the error that occurs during the application of the first portion, wherein the re-application position indicates where the robot begins applying a second portion of the material;
• establishing a tracking position for the robot along the motion segment in response to the error that occurs during the application of the first portion, wherein the tracking position relates to the re-application position;
• automatically determining a backup distance indicating where the robot is relocated relative to the re-application position;
• relocating the robot to a backup position based on the determined backup distance;
• moving the robot from the backup position toward the re-application position;
• said method characterized by monitoring the tracking position as the robot moves from the backup position toward the reapplication position to instruct the robot to begin application of the second portion of the material to the workpiece at the re-application position to prevent any gaps or overlaps in the material on the workpiece.

An intelligent error-recovery method for controlling a system having a robot to ensure that an operational parameter is achieved after an error occurs in the system, said method comprising the steps of:

• moving the robot along an operating path between a first position and a second position;
• performing an operation with the robot as the robot moves, wherein the operation that is performed requires the operational parameter to ensure that the operation is completed;
• discontinuing the operation performed with the robot in response to the error;
• establishing a transitional position when the error occurs, wherein the transitional position indicates a location of the robot along the operating path when the error occurs;
• relocating the robot to a restart position after the error occurs;
• moving the robot from the restart position toward the second position;
• said method characterized by verifying that the operational parameter is achieved at least by a time the transitional position is reached by the robot as the robot moves from the restart position toward the second position to ensure that the operation is completed by the robot.