Abstract: A method of determining the current orientation of the wrist output of a closed-loop robot wrist having at least one actuator, where the actuator has a displacement sensor, includes generating a look-up table having table orientation data corresponding to the orientation of the wrist output for specific table displacement values of the displacements of the actuator. The method generates displacement signals representative of the displacement of said actuator; selects from the look-up table a set of table orientation data as determined from the displacement signals; and determines the current orientation of the wrist output from that set of table orientation data. Analysis of an equivalent open-loop mechanical model of at least one link of the closed-loop wrist may be used to generate the look-up table.

Abstract: The present invention is an apparatus for and method of determining the three-axis center of gravity of objects. The apparatus of the present invention has a conveyor assembly that receives a package from an upstream conveyor path. After being received, the package is decelerated in a controlled manner to a complete stop. Package motion is then resumed to propel the package off the apparatus onto the downstream conveyor path. During both the deceleration and stop periods, signals are generated by load cells supporting the conveyor assembly. These generated signals are representative of the load applied by the package at the load cells. The three components of the center of gravity of the package are calculated from these generated signals.