A Self-Propelled Deep-Seabed Miner and Lessons From Shallow Water Tests

A self-propelled miner for deep-seabed manganese nodules was developed for the purpose of evaluations of mining performance and viability for scale-up. The test miner crawls on the seafloor by two tracks and separates the nodules from seafloor by hybrid pick-up device. The weight and size are 10tons in air (5tons in water) and 5m(L)×4m(W)×3m(H), respectively. It is operated electro-hydraulically in real-time via umbilical cable. Software’s for real-time remote control, monitoring and database systems were developed as well. Shallow water tests of the test miner were performed in 100m water depth of an inshore condition site. Glass beads (d = 19mm, m = 10g/ea) were made for artificial nodules instead of real nodules. Non DP barge (W = 19m, L = 51m) was used as surface unit. The sea tests showed that the fundamental performance of the test miner is confirmed and at the same time functional modification and improvement in sensing and measurement system are addressed. This paper describes about the development methods of the test miner and lessons from the sea tests.