As the saying goes, there are no coincidences, and there are many coincidences in reality. The unit's first field business after the Chinese New Year in 2020 was completed by my team. The main content of the field business is single beam and sonar measurement, and local small fishing boats are rented. I led the team to complete the last field business before the Lunar New Year in 2021. The main content of the field business is multi-beam. The multi-beam equipment used is Reson7125 and the attitude equipment is POSMV. This combination was installed on my measuring boat for my colleagues not long ago. Since the place of operation is in Dongying, far away from Qingdao, the unit felt that there was no need to use my own boat and the cost was high, so I took the equipment to rent a boat in Dongying to complete the field business.
Before sailing, I communicated with the captain. Because of their frequent measurement work, their ship has a rack to fix the Reson7125, so you only need to prepare the Reson7125 connecting rod. I also brought my own shelf because I was worried that the shelf was inappropriate. In addition, I was afraid that Reson7125 would have problems. I brought a single beam for backup. It can be said that I have made sufficient preparations and must finish the field work. The reason for this urgency is that the owner is more anxious, and the actual weather conditions are: Dongying sea seems to be frozen, this time I can’t do it, maybe it can only wait for the next year.
I came to the ship and looked at the mounting frame. It was indeed not bad, and it was indeed a civil scientific research ship. Hearing from the guys on the boat, some measurement units used their mounting brackets and they also made one. I took a picture of this mounting frame in three directions, as follows:
As can be seen from the above picture, a thick layer of ice has formed in the harbor basin, which is larger than 10cm by visual inspection
Seeing such thick ice, I don’t know if I can do it. It was the first time I encountered this situation. This time I was able to come out, but I also believed in the owner's words, so I can do it. After arriving at the ship, I asked the boss of the ship, and the boss said there was no problem. While talking, a fishing boat went out to fish.
After finally getting out of the port, I found that there was an ice belt several nautical miles wide between the harbor basin and the open sea. The ice belt was not connected into one piece and was relatively broken and could be washed out. Ride the wind to break the ice, Ollie give it!
After reaching the measurement area, there are still some swells, and after the swells are eliminated, the level 5 wind and waves have been maintained during the operation. The appearance of Reson7125 after installation is as follows:
The front and rear are tightened with steel cables, and the sides are tightened by the bottom steel cables. This kind of packaging belt tensioner is not as good as the steel cable tensioner, because after it is tightened to a certain level, it can no longer be tightened. The advantage is that it is not easy Corrosion, can be used many times, but the cable tensioner is basically useless once.
Due to the low temperature, the water on the ship turned into ice, which was very slippery. It took a lot of effort to install the Reson7125.
After installing Reson7125, link the indoor data line, POSMV provides position, attitude, heading and time synchronization to Reson7125.
The acquisition software of Reson7125 is PDS2000, set up the project, open the controller of Reson7125, check Roll Stabilization, and select Best Coverage as the mode
Then you can work and complete the survey lines one by one. The leader of the boat has a very good line running level. He is indeed a veteran, basically don't care, set the automatic line change, and they start to run the line. And this time I got a little bit off the chain, got seasick, and vomited once. Ugh!
Since the tide level needs to be measured, I brought 2 water level gauges, tied them to the ship’s small iron anchor, placed them on the bottom of the sea, and used a rope to tie a floating ball to mark the sea surface. Since the measurement area is on a customary route, in order to prevent the ships from touching it, Attach an AIS position indicator to the sea end. Because it also has a flashing light function, it has a warning function to prevent fishing boats from trawling.
Another advantage of the position indicator is that it can be seen in the ship’s AIS system to prevent the loss of the water level gauge.
The ship symbol in the middle of the picture above is own ship, and the white triangle and long string of white characters on the north side are the AIS position indicator.
After 30 hours of continuous operation, all tasks were completed and the icebreaker returned.
For more inquiries, see xiaok marine surveying and mapping network and the public account of the same name