Improvement of the Anti-Sway Control in Transfer Cranes Using an Accurate Image Measurement

从安全和自动化的角度出发，在提高吊车摇摆测量精度的基础上进行研究，以达到更高的集装箱装卸作业防摇摆控制性能。由于小车位置下边界条件的变化，使得安装了CCD摄像机的梁-小车系统的振动特征频率不能从梁上的应变片上准确地给出，因此，基于应变片的信息，摄像机角度的偏转很难表示为特征振动的线性组合。然后考虑了直接测量摄像机的偏转角，提出了一种基于卡尔曼滤波和极大似然法的方法，在小车上安装两个加速度传感器。该方法在桥墩和金属杆异常诊断中的两个应用表明了该方法的有效性，这两个应用在下文参考文献所示的研讨会上进行了介绍。然而，由于基于图像数据处理时间的采样频率不足、对工作环境的承受能力、定期维护的需要以及增加加速度传感器的测量系统成本的增加，我们建立了起重机的动力学模型，提出了一种只使用两个加速度传感器的防摇控制系统，该系统不使用CCD摄像机来测量吊车的摆动和转动的位移和速度。考虑实际参数的数值仿真结果表明了所提出的测量与控制系统的有效性。关于上述结果的详细情况见下文参考文献。

It was studied based on the improvement of accuracy in measuring the sway of spreaders to achieve higher performance of anti-sway control in the operation of containers by transfer cranes from the viewpoints of safety and automation. Since the characteristic frequencies of the vibration in the girder-trolley system, where a CCD camera was attached, couldn't be given accurately from the strain gauges on the girder because of the variation of boundary conditions under the position of trolley, it was found that the deflection of the camera angle was difficult to express as a linear combination of characteristic vibrations based on the information from strain gauges. Then we considered measuring directly the deflection angle of the camera and proposed an approach based on the Kalman filter and maximum-likelihood method using two acceleration sensors on the trolley. The usefulness of the approach was shown by two applications on anomaly diagnoses of bridge piers and metal poles which were presented at the symposiums shown in references below. However, due to an insufficient sampling frequency based on the processing time of image data, the endurance for the environment under operation, the need of regular maintenance, and the increasing cost of measuring system by adding acceleration sensors, we constructed the dynamics model of the crane and proposed an anti-sway control system which used only two acceleration sensors without using CCD camera to measure a displacement and a velocity of not only the sway but also the rotation of spreader-container. The usefulness of the proposed measuring and control system was shown by the numerical simulations considering practical parameters. Details on above results were presented as the article shown in references below.