Development and Application of Real-Time Monitoring System

Abstract No. : 020-0605

Development and Application of Real-Time Monitoring System

for Efficient Operation of Workplace in Shipbuilding

Authors

Tae-Hyun Baek*, Byeong-Yeol Lee, Tae-Hoon Choi,Ji-On Kim, Dae-Soon Kim

* : Senior Research Engineer,

Tel: 82-52-202-3203 Fax: 82-52-250-9587 E-mail :

Hyundai Industrial Research Institute, Hyundai Heavy Industries Co., Ltd.

POMS 22nd Annual Conference

Reno, Nevada, U.S.A.

April 29 to May 2, 2011

Abstract

Real-time location tracking system has been developed for space utilization and productivity improvement in shipbuilding.An optimal work order approach and a real-time location algorithm based on wireless network technology were designed for work scheduling and spatial assignment. As a result, it is possible to track worker's movement and location of work object by real-time monitoring system based on RTLS(Real Time Location System) for indoor workplace. In case of outdoor workplace it is studied to apply for grasping work safety and unbalanced workload improvement by real-time monitoring system based on IDGPS (Inverted Differential Global Positioning System).

Through simulation to consider various situations of shipbuilding yard, this study demonstrates the effectiveness of real-time monitoring system for efficient operation of workplace.

1. Introduction

A ship is assembled from many blocks which are partially assembled units. During the shipbuilding process, numerous components and blocks are stocked throughout the shipyard. Having too many unneeded parts and blocks can lead to a decrease in the productivity of the shipbuilding.

To handle this problem, the real-time management of logistics for the parts and blocks in shipyard has been achieved through the latest IT technologies such as GPS(Global Positioning System), RFID(Radio Frequency IDentification) and WiBro(Wireless Broadband).

Recently, the status of South Korea as the leader in the world shipbuilding industry is being threatened by China. Therefore, technological innovation in this industry is needed to strengthen competitiveness. Since China has almost caught up with us in the field of ship design technology, a great improvement to production technology is needed to enhance cost competitiveness.

This paper describes real-time location tracking system which has been developed for spare utilization and productivity improvement in shipbuilding.And an optimal work order approach and a real-time location algorithm based on wireless network technology were designed for work scheduling and spatial assignment. Also, through simulation to consider various situations of shipbuilding yard, this study demonstrates the effectiveness of real-time monitoring system for efficient operation of workplace.

2. The optimal algorithm for task assignment and real-time location tracking

For building the schedule of a fabrication shop is so complicated because it needs to consider the traditional planning and scheduling problem as well as the spatial allocation of blocks within the limited workspace. To solve the problem, we adopt the optimal algorithm for task assignment and real-time location tracking to maximize the space utilization of the fabrication shop by efficiently arranged blocks and keep the workload balance uniform.

As shown in Figure 1, the optimal algorithm for task assignment and real-time location tracking searches for the best layout at the fabrication and the appropriate assignment of working teams by the most efficient method.

Figure 2 and Table 1 show the comparison of results obtained by algorithm.An experiment has established the fact as there are no significant differences between the real location values (x, y point) of workers group and the measured through tested results by Aeroscout’s RTLS engine.

To achievethe correct result, the experiments for various situations of the fabrication shopwere carried out for about 6 months in extremely same conditions such as quantity and location of AP for a fabrication shop (30m x 50m x 25m) and the range of radio frequency for communicating between control center and workers.

Figure 1. The optimal algorithm for task assignment and real-time location tracking

Figure 2. The comparison of result obtained by algorithm

Table 1. The application result obtained by algorithm

Acquiring the exact location values of workers in the fabrication shopproved to be very difficult due to the reverberation and collision of radio signal with the metalmaterials of the assembled blocks

3. Real-time monitoring system

In order to improve productivity as space utilization, workload balance and ratio of on-time delivery in the fabrication shop, the real-time monitoring system was developed as below Figure 3.

Figure 3. Configuration of the real-time monitoring system

In order to improve productivity as space utilization, workload balance and ratio of on-time delivery in the fabrication shop, the real-time monitoring system was developed.

The usefulness of the real-time monitoring system is proven by the experiments that compared theplanning and scheduling by the system with the manual operation and to resolve the difficulties in getting exact real location data because of reverberation and collision of radio signal to the blocks fabricated by the steel materials, the location compensationby real-time location tracking algorithm isapplied.

Table 2 shows the comparison of results obtained by the real-time monitoring system. To evaluate the performance of system for the fabrication shop, the tests for the performance of space utilization, workload balance and ratio of on-time delivery are conducted by comparing the real-time monitoring system with a manual operation.

Table 2. Comparison of space utilization, workload balance and ratio of on-time delivery

4. Conclusion

Our integrated real-time logistics management system is the shipbuilding industry’s first system to be used as a key technology to construct the digital shipyard. It improves efficiency by fundamentally changing the production process. At first, the location measurement equipment for the blocks has less than 0.5m allowance by combining the various kinds of technologies like RFID, Digital Compass, PDA(Personal Digital Assistants) and so on. Second, WiBro communication network in the shipyard greatly improves the speed and accuracy of data communication. And lastly, the block operation system based on the optimization algorithm builds the real-time transportation schedule for the block transporters. By doing so, the total number of transportation of the parts and blocks is decreased by more than 10%.

By combining the latest ITs and traditional shipbuilding technologies, we can measure the location and the shape of the parts and blocks in the shipyard and monitor their real-time transportation. This system reduces logistics costs improve delivery performance by real-time block monitoring and building the optimized block transportation schedule.

The developed technology is expected to be implemented in not only a production line but in the entire shipbuilding processes. In addition, a synergy effect is also expected by interfacing with the main systems such as ERP. In conclusion, we have developed a key technology to our position as the global leader in the shipbuilding market.

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