We all live in a ... black-and-yellow submarine.
With the much-loved Beatles song (We all live in a yellow submarine) playing in everyone’s head, the little two-tone ecoSUB puttered across the NMU swimming pool carrying the hopes of humankind to stave off environmental catastrophe in the oceans and “create a better life for all”.
Leading the unusual demonstration, British marine engineer Terry Sloan said the craft had been snapped up in the defence sector, by oil and gas exploration companies and by oceanographic researchers.
“Depending on the sensors loaded, it can be used to gauge multiple climate change signals like shifts in temperature, salinity and the density of plankton.
“It can also be used to monitor wave height and direction, to sniff out oil leaks from undersea pipes and perhaps even in the future to quantify microplastic pollution,” he said.
The pool demonstration was part of the 2nd International Indian Ocean Expedition, aimed at sustainably expanding the Indian Ocean’s blue economy and “avoiding a dead ocean”.
The expedition, convening for the first time in Africa, is being hosted by NMU.
Sloane said two ecoSUB models had been designed and manufactured from aluminium and 3D-printed nylon by ecoSUB Robotics in Surrey, sponsored by the UK government.
The smaller craft, at 660mm long, could dive 500m and was presently being marketed at approximately £10,000 (R189,000).
The larger ecoSUB was 1m long, selling for £20,000 (R377,550) and could dive to a depth of 2,500m and range for 18 hours, or 65km at a time, powered by a dozen alkaline torch batteries.
“We were approached by the National Oceanographic Centre at Southampton University and they wanted an AUV [autonomous undersea vehicle] that was affordable, agile and easy to use, that didn’t need cranes to launch it.”
It could be deployed from the side of a boat or from the beach and was guided by a mission worked out on a command-and-control computer interface using maps of the seabed, Sloane said.
Communication took place via the internet, satellite or acoustic telemetry, where data was encoded into sound waves directed through the water.
“EcoSUB can spiral down through the water column or be sent off on a long-range patrol travelling at a maximum 1m per second.
“When it needs to dive or surface, it shifts its battery pack accordingly.”
While the ecoSUBs were engaged in their planetary rescue job, they had occasionally run into trouble with marine heavyweights, he said.
Several craft had been lost after apparently being swallowed by whales.
South African oceanographer Prof Mike Roberts, head of the R144m pan-African marine food security project Solstice anchored at NMU, and coordinator of the Indian Ocean conference – said he was impressed with what he had seen.
“I have discussed with my colleagues and I’m hoping we can buy three of the bigger ecoSUBs for our work.”
Solstice is looking at case studies of fisheries collapse in East Africa and in the east and southern Cape, where the chokka industry ruptured in 2014 before recovering later.
The ecoSUBs could be of vital assistance in getting to the bottom of this marine mystery.
“They could criss-cross the area where the chokka egg aggregations occur on the seabed to give us a dynamic picture.”