Advantages of using command shaping over feedback for crane control

Abstract

Cranes are the primary heavy lifters for a wide variety of industries. However, all cranes share the same important limitation on efficiency: payload oscillation. Given the significance of cranes, it is not surprising that a large amount of research has been dedicated to eliminating this oscillation. Much of this research has been directed toward feedback control methods. Another portion of the work has focused primarily on command-shaping methods. This paper explores the problems with using feedback for crane control, which include the difficulty in sensing the crane payload, widely varying system dynamics, and human-operator compatibility. In light of these problems, input shaping is shown to be a favorable solution.

Dynamics and swing control of double-pendulum bridge cranes with distributed-mass beams

“…Simulations demonstrated the effectiveness of the observer and the controller [8]. However, there are some obstacles toward the application of the feedback controllers, including the difficulty of accurately sensing the payload and its velocity, and the conflict between computer-based feedback controller and the actions of human operator [9].…”

Training Simulator for Acquiring Operational Skill to Operate Overhead Traveling Crane while Suppressing Load Sway

“…Since the motion of the cart in a crane operated by momentary switches is limited as shown in Figure 3(b), it is di cult to apply common vibration suppression approaches such as the notch lter method [21,30]. erefore, the input shaper approach, whereby the vibration is suppressed through the application of multiple signal pulses, has been proposed [19,31,32]. is approach is a type of feedforward vibration suppression control, where the vibration caused by the original signal can be suppressed by the countervibration caused by the phase lag signal.…”

“…Furthermore, the auxiliary effectors installed to the crane hook or the cart have been developed for suppressing the load sway [15][16][17]. e feedforward control systems taking into account the load sway suppression have been proposed using the optimal control approach [18], the input shaper [19], the trajectory planning by neural networks [20], and the notch filter [21]. Many researchers have dealt with the problems with regard to the load sway suppression in the overhead traveling crane.…”

Combined Input Shaping and Feedback Control of a Double-Pendulum System Subject to External Disturbances

“…Feedback control methods have also been well studied, and implemented to reject external disturbances [18]. These techniques can successfully reject external disturbances, but do not perform particularly well with motion-induced oscillations of the payload [19].…”