Penta Ocean Construction : Development of an Oceanographic Survey Drone with Abilities to Take Off, Land and Sail on the Sea

Tokyo, Japan - May 31, 2024 - Penta-Ocean Construction Co., Ltd.(President, Takuzo Shimizu) and Prodrone Co., Ltd.(President, Shunsuke Toya) have developed "Penta-Ocean Vanguard-DroneAqua"(hereinafter POV-DA), an oceanographic survey drone with abilities to take off, land, and sail on the sea.

POV-DA, designed to take off and land on water, is deployed with a high precision GNSS satellite, thrusters and a depth measuring sonar (photograph-1). Once landed on water, the information on the current location (X, Y, Z) and the water depth is transmitted and displayed in real time on the screen of the remote controlling console of operators on land. By entering the XY plane location of the monitoring point on the control screen, the mounted thrusters underwater propel the drone to sail on the water, or helps it to maintain the vehicle position at the monitoring point, regardless of waves and swells. Thanks to the above features, 1. Bathymetric survey and 2. Wave observation can now be performed effortlessly and efficiently by means of an automated remote control from land.

Photograph-1: POV-DA (left: full view, right: measuring operation on water)

1. For bathymetric survey

In construction management of projects involving construction of breakwaters, quay walls, etc., depth sounding by dedicated boat^*1 or lead sounding^*2 are commonly applied, due to lack of visual references of underwater construction. With the introduction of POV-DA, time required for depth survey can be reduced. In addition, because the measured data is transmitted to the control screen in real time, the apparatus enables operators to monitor the progress of underwater construction or to analyze the excess or lack of dumped soil, expediting decision-making on the necessity for further soil dumping. The team confirmed that the surveying feature of POV-DA demonstrates approximately +/-10cm differences compared to conventional depth sounding, proving the accuracy level considered sufficient for practical application in construction management.

2. For wave observation

In marine construction works, construction management and safety management are performed based on various weather and marine forecast data or wave height measurement data in the vicinity of the project site. Furthermore, in order to assess the project feasibility pre-construction, visual checking from the coastline is performed. With the introduction of POV-DA, wave height and wave period derived from GNSS data are displayed on the control screen in real time, enabling a construction manager to assess the wave conditions at the project site and to expedite the determination of the feasibility of marine works. The team confirmed that the measurement results using POV-DA shows +/-10% or less differences on average compared to measurement results using wave meters, proving the accuracy level considered sufficient for practical application in construction management.

In addition to contributing to more efficient construction management and expediting the determination of feasibility of marine works, POV-DA's feature to take aerial shots from above offers emergency support in times of disasters by providing real-time updates of damages both on land and under water.

Going forward, POV-DA is expected to hold additional equipment such as a multi-parameter water quality meter and a water sampling device needed for more comprehensive marine observation, further extending its scope of use to other arenas including preservation and surveying of coastal environments in marine construction projects.

*1:Depth sounding: Water depth measurement using single-beam or multi-beam sonar sounders mounted on a moving boat
*2:Lead sounding: Water depth measurement by throwing in a rope with a lead weight attached to the end and reading the depth values on the rope from the seafloor to the waterline