While the automation of overhead travelling cranes is progressing, the ‘dynamic lift off’ process is still manually operated. In this paper, we thus developed an automatic ‘dynamic lift off ’system based on a trolly-position control system using wire tension. The system suppresses swaying of the suspended load after the dynamic lift off by correcting the suspension position so that the combined direction of the tension of each suspension wire matches the gravity direction of the suspended load. As a result of the experiment using the physical simulation using Unity and the developed scale model, we confirmed that the sway of the suspended load can be suppressed by using the automatic trolly-position control system than the manual operation.

This paper discusses a training system to acquire operational skills of an overhead traveling crane. Cranes are frequently used in various fields. Skilled workers are required for operating safely and efficiently the crane. However, acquiring the operational skills spends a lot of time. The training system that the trainee can learn safely and efficiently operational skills of suppressing load sway and positioning using overhead traveling crane simulator is developed in this study. The teaching information and the score board for learning the operational skills of suppressing the load sway and positioning are displayed in the crane simulator. The displayed teaching information is proposed by the theoretical analysis of the behavior of the overhead traveling crane. The efficacy of the proposed operational training system was verified the experiments with subjects.

One of the problems of overhead cranes used for transporting heavy loads is causing long-lasting residual vibration without using dampers, which lowers safety and work efficiency. The purpose of this study is to suppress the residual vibration of the pendulum in the 1D translation type overhead crane by deciding the trajectory of the trolley by vibration manipulation function (VMF). We attempted open-loop finite-time-settling control by using VMF as a finite-time-settling function. We performed experimental works of vibration control transfer of the overhead crane by using a stepping motor to faithfully reproduce the transport trajectory calculated by VMF. Results of experiments was compared with simulations.

In recent years, there is a need for development of control method that stabilizes a load of crane. A number of vibration control methods have been proposed and those method divided into two main methods: feedback control that uses sensor measuring vibration of load and sequence control that makes motions for controlling vibration in advance. However, the former has some problems such as rise of cost and complication of the equipment due to installing sensors and the latter has some problems such as malfunction of vibration control in a variety of operations. For these problems, we propose control vibration method that is based on feedback simulation using a dynamic model of the crane. In the proposed method, sensorless vibration control is realized by inputting control variable generated in simulation space into a real crane. Furthermore, the feedback controller in the simulation is designed to adapt wire length change. The proposed method is applied to a real overhead crane and sufficient vibration control performance was obtained in two verification experiments, that is, 1-horizontal axis experiment with varying wire length and 2-horizontal axis experiment with constant wire length.