Touchscreen crane control interfaces with oscillation suppression

It is often very difficult for human operators to control cranes due to their slow responses and lightly-damped payload swing. The control task is made even harder by awkward control interfaces. Portable touchscreen devices offer the opportunity to improve the control interface by replacing traditional push-button pendent and joystick-based controllers. This paper presents several classes of touchscreen interfaces that are coupled with an oscillation-supressing control system. Some interfaces are further augmented with a rotating reference frame of control that changes the control directions based on the direction that the touchscreen controller is pointing. Results from operator studies demonstrate the relative effectiveness of the interfaces and compares them with a traditional push-button pendent.