Acoustic system for automated monitoring
of the crane-moved cargo position
Development of a radically new acoustic system for automated monitoring of the position of a cargo moved by deck-mounted cranes or cranes used in construction in the course of loading and unloading operations and construction works. The use of such a system is most efficient when the works are carried out in poor visibility conditions, namely, in the nigh time or in adverse weather conditions (rain, mist, or snowfall).
System components and the principle of operation
The system consists of an acoustic radiator (beacon) mounted on the crane hook, a receiving antenna array containing four microphones placed in the area of the cargo platform, and a hardware unit. The principle of operation is as follows. The array receives the signal from the beacon, then the signal is processed, and the cargo position is determined in the three-dimensional space. This information is transmitted through the ultrashort-wave radio channel to the display installed in the crane operator cabin.
Degree of readiness
Optimal algorithms are developed for a continuous determination of the crane-moved cargo relative to the point where the cargo should be placed. A computer simulation of the system is performed. A prototype of the system (without the radio channel) is manufactured and tested in full-scale conditions. The tests were performed using a KB-300 crane with a maximal distance of 25 m between the center of the receiving array (the cargo platform) and the crane hook. The error in the determination of the cargo coordinates relative to the center of the cargo platform was ± 0.7 m. Figure represents the dynamics of the determination of the cargo coordinates in the course of its upward and downward motion. The tests were performed on the background of an elevated noise level. The subsequent measurements and estimates showed that, for the optimal frequency of transmitted and received signals, the cargo coordinates can be determined to within ± 0.3 m.
The results of work performed at the Acoustics Institute are sufficient for the development of acoustic systems for automated monitoring of the crane-moved cargo position. The institute is ready to fulfil the order for the design and manufacture of such systems with a complete set of equipment.