Development of a suspended-load rotation-control device for cranes with gyroscopic damper and control by wind force (concept, modeling and experiments)

Abstract

Currently, cranes are used as transportation equipment in various industries such as construction, distribution and manufacturing. In the construction field, materials and products suspended from a crane hook are called suspended loads. Basically, the crane hook is a free rotation mechanism and lacks a rotating power function, so the suspended load under the crane hook rotates when exposed to strong wind and it remains extremely dangerous when working at high place. Accordingly, in this study, we have developed the suspended -load rotation-control device. Then, we focused on the characteristics of passive control that generate a large torque with respect to a short-term disturbance around the vertical axis of a uniaxial mechanical gyroscope. From this characteristics, a mechanical gyroscope is installed in a part of the device, and the suspended load is rotated by a motor-driven device hook. Then, the reaction torque generated when the suspended load is rotating is surpressed, and the suspended load is stopped at an arbitrary position. Actually, this device is applied to carry in materials and products at various sites. However, since several problems were found in the operation of this device, this study examined how to improve them. To shorten the offset time of the flywheel tilt angle, we examined two items. The first aspect of improving this device involves the study of a gyroscopic damper in which springs are added to the gimbal side of the mechanical gyroscope. The second item of the improvement method of this device involves controlling the posture using control by wind force. This paper introduces ways that improve the mechanical gyroscope offset function of this device. Next, to confirm the effectiveness of the gyroscopic damper and control by wind force are verified and the contents of the physical model created based on the verification test are also described.

Keywords

• gyroscopic moment
• modeling
• mechanical gyroscope
• gyroscopic damper
• wind force