At Berkeley Process Control's Technology suite at the Semicon West Show this year, one of the main demonstrations featured a broken robot. How crazy is that? Turns out there was a method behind this madness, which was to showcase Berkeley's new BX motion controller. "The controller can detect a mechanical problem and automatically compensate for it, maintaining move or motion profiles regardless of the health of the robot," explained Mario Lento, senior product specialist, who was tending to the robot. "It enables even sub-par mechanisms to operate as designed." The controller works by maintaining velocity and position following information in realtime while the current (or torque) loop is closed to preserve the quality of the defined motion. That real-time state of the current (or torque) is known and incorporated in Berkeley's suite of In-Situ diagnostics. Lento explains that this state information is measured and controlled in a variety of ways to determine how much effort is required to force a sickly robot to comply with its required quality of motion. For robots in critical condition, say there is not enough torque to maintain the required profile, the controller will generate an error or report profiles outside the limits.