SOLUTION 02 / Robotics

Yanmar eases workload with Auto-docking System and Auto-navigation Robotic Boat to create a safe and secure future

Research & Development Center
By automating the docking operation which has always been stressful for users, Yanmar offers safe docking with an error range limited to only within few tens of centimeters. By adding this to the Auto-navigation Robotic Boat, Yanmar not only contributes to the marine business, but also alleviates workload for those working in the fishery and marine business, leading to alternative labor and labor savings out on sea.

ISSUE

A new challenge to reduce user's burden and create a society where people can work with a peace of mind

Marine business is one of Yanmar's strengths. We continue to support offshore workers with a variety of our products and services born from a new perspective. Yanmar focuses on “docking”* which requires skill in ship navigation but is a huge stress for users. Yanmar has undertaken the development of an "Auto-docking System" for smooth and safe docking without any troublesome operation, and an "Auto-navigation Robotic Boat" that automatically determines safe route to control sailing at sea. The development of these systems will be a great advantage not only for the marine business, but also for the fisheries market where the population of workers is decreasing and the demand for aquaculture is expanding, benefitting the dangers involved in offshore operations. Since 2017, Yanmar has been developing these systems while considering to alleviate the burden of offshore laborers by replacing and reducing offshore work.

Initially, we began to develop this technology for the commonly used single-propeller and single-rubber boat, similar to those seen in automobiles. As the project proceeded, it was clear that an enormous amount of man-hours was necessary for development due to the difficulty in controlling docking for a single-propeller and single-rudder ship. The reason, being not only its vulnerability in keeping a stable position from winds and waves, but also its lack of flexibility for directly applying force in a lateral movement. With the desire to release a new product as quickly as possible, we switched to applying a twin-propeller and twin-rudder ship equipped with multiple propulsion units and decided to consolidate man-hours for development. By installing a propulsion distribution equipment that can move the ship in any direction and applying the dynamic positioning system that we developed in 2015, Yanmar finally completed the basic technology for the Auto-docking and Auto-navigation system.* To approach the boat to the pier, raft, or shore on the ocean.

SOLUTION

Yanmar will solve customer problems and continue to take on the challenge of creating a future society and enriching people's lives.

The key to automatic ship steering is the ability to estimate its own position to identify the location of the vessel. Although deviation of several meters occur with GNSS including GPS, we aimed to reduce the error within few tens of centimeters with our Auto-docking System. During the early stage of development, we adopted the Real time kinematic(RKT), which is also used in Yanmar's robot tractors that are actively involved in the agricultural field. We set up a base station on the harbor side and developed the system that outputs correction signals to improve accuracy. However, it could only be used at a specific port where the base station was set up, and there was also a safety issue of not having sensors to recognize its actual surrounding environment. For this reason, the next step was to equip the ship with 3D-LIDAR, which is a sensor that recognizes the surrounding environment, and focus on developing a system that estimates its own position with high precision by measuring surrounding objects.

As a result, we succeeded in keeping the self-position estimation error within few tens of centimeters even without a base station. Moreover, it became possible to automatically direct the boat using its surrounding environment just by designating the location to dock. Since the start of development, we were able to reduce the time it takes for Auto-docking from four minutes to a more practical two and a half minutes. During navigation offshore, a rough wide-area map is created with a radar to set navigation route. While sailing along this route, the surrounding environment is explored in detail using 3D-LIDAR, so that nearby obstacles can be detected. In addition, 3D-LIDAR is used to generate high-resolution map for navigation and docking in narrow space. Auto-docking System selects a safe route with less risk of collision and automatically operates the process from navigation to docking. The successful result was achieved from the unwavering determination of the development team to create a system that users can navigate safely and freely dock the vessel in its position without stress.

3D-LIDAR of the bow accurately captures the surrounding environment.

Wide area map was created offshore to set navigation route.

High-resolution map was generated for inside a small port or for docking.

RESULT & FUTURE

Applying technology in various fields

Development through trial and error. There is no other way to check whether the system works safely and smoothly except by testing in a real environment. However, selecting a test environment is extremely difficult because of the lack of test fields in Japan. With the cooperation of Yanmar Marina, we were able to obtain permission from local administration such as city and prefecture as well as fisheries including local residents to design and construct a mock environment depicting an actual harbor. We were able to fully evaluate under a mock environment for one and half months. We were able to fully evaluate under a mock environment for one and half months and test under various weather conditions such as rain, snow, and strong winds.

There were many unexpected problems that happened unless we tested such an evaluation with actual vessel. For example, the appearance of buoys and rafts when observed by radar in this system was different from what we expected. We also found out the risk of catching the rope between buoy and its anchor even if buoys could be avoided, and also we became aware that these positions are unstable due to changes in the weather condition. By incorporating environmental information into the route plan, combining multiple sensors to improving the detection rate, and so on, we established more reliable and safe navigation system. For further safety, we are also working on measures against hard conditioned weather. Regarding wind, it became possible to navigate within an error of 50cm while sailing at a wind speed of 7 m/s.

Yanmar always aims to establish a safe and highly accurate system. In the future, we will continue research and development to apply the technology to various fields.

Docking Test at Yanmar Marina

Evasive testing for buoy and raft

INTERVIEWTo establish a sustainable robotics technology to pursue prosperity for the people and nature

While Auto-docking System was being developed, many companies and government agencies have asked about the system. Yanmar is also capable of offering consistency from basic research from engines and hull to systems, development, and production of ships. Yanmar's strength is that we can take responsibility for all manufacturing and handle customization with flexibility. In this way, widely introducing the use of Auto-navigation Robotic Boat and Auto-docking System will liberate workers from harsh environments in the fishery and marine businesses, leading to work with safety and peace of mind.

Naohito Hara, person in charge of control technology, said, “This developing technology is just beginning. Currently, these systems are effective only under limited conditions such as inside a harbor. We want to provide the technology to people who work in the aquaculture business or involved in various operations out on sea, to offer a more practical system environment.” Tomoya Fukukawa, in charge of research and development of Auto-navigation Robotic technology states, “To offer genuine security, we could approach the psychological and emotional aspect of the customer when pursuing technology.” Yuichiro Dake, in charge of recognition technology states “We would like to launch robotics technology that will continue to be practical rather than just releasing into the market.” In this way, Yanmar will solve customer problems and continue to take on the challenge of creating a future society and enriching people's lives.