Submerged test of the CCDE system

1. Configuration of the submerged test vessel

In order to test the developed CCDE system in water, a steel pressure vessel of 10 meter depth rating was constructed. The vessel is 4.2m long, 0.95m in diameter and weighs 2810kg including the CCDE system, and has a separable structure similar to that of the R1 robot.The inside dimensions of the vessel for the power generation unit and the CO2 absorbing unit are those for the R1 robot. Since a cryogenic tank for the R1 robot was under construction at that time, a commercally available small cryogenic tank for the LOX was installed in the vessel.

The CCDE control system, and a dummy load to dissipate the electric power generated by the CCDE, are placed outside the water and are connected to the CCDE through electric cables.

2. Submerged test

After various kinds of land tests, submerged tests of the CCDE system were carried out in a fresh water pool as shown in Fig. 9. The capability of the CCDE system in water, such as the performance in steady and transient states, the start/stop sequence and static trim angle operation up to +/-25 degrees, have been investigated. The copper tubes around the vessel are a tubular heat exchanger to cool the CCDE system in the vessel by surrounding water. The test result ensured that the heat exchanger for the R1 robot has enough capacity of cooling even when the vehicle stays still. Throughout the tests, the CCDE has indicated almost the same satisfactory performance as the results obtained in the land test.

Fig.9 Submerged test of the CCDE

The next series of CCDE submerged tests included the endurance trial and the pitch, roll and yaw test reflecting the actual behavior of the robot.


The R1 robot is a cruising rype AUV with an air independent power of Closed Cycle Diesel Engine for seabed scientific survey. The design and construction of the robot including a main pressure vessel, thrusters, steering gears, navigation systems and control systems have been almost completed. Submerged tests of the CCDE system are underway and the results show sufficient performance as a power system for the R1 robot.

The fabrication of the R1 robot is being carried out. The first sea trial will be conducted in the fall of 1995.


The R1 project is financially supported by the Ministry of Education and Science, and currrrently promoted by the members of the R1 Research Group.


Last modified: Mon Jun 5 18:13:59 1995