Self-corrective nut running for robotic applications

A method for position correction relative to a workpiece of a machine with a nut runner comprising:

• engaging the workpiece with the nut runner;
• operating the nut runner;
• determining whether the nut runner operation was successful;
• if the nut runner operation was not successful, measuring, after determining the nut runner operation was not successful, at least one of a force or a moment resulting from engaging the work piece with the nut runner;
• determining a pose error from at least one of the force or the moment, wherein the pose error defines a misalignment of the nut runner relative to the workpiece and a direction thereof;
• wherein determining the pose error includes:
• the measuring, by a sensor, the force and the moment;
• and
• deriving, by a controller, a position vector r by calculating r=F×M/F·F, where F represents the force and M represents the moment;
• repositioning the nut runner in the direction of the pose error to correct the misalignment;
• wherein repositioning the nut runner includes, using the position vector r to align the nut runner with the workpiece;
• and
• recording the pose error, and using the recorded pose error to correct a programmed position of the motion for future operations.