from SeabedRig.com
Advances in drilling technology tend to be evolutionary, not revolutionary. Floating rigs, dynamic positioning, top-drive systems, measurement-while-drilling, automated rig floors, and other important advances were logical next steps, not radical makeovers.
Many of us have long been fascinated by the possibility of locating drilling equipment on the seafloor, particularly for deepwater wells. Why operate from a massive floating vessel that requires a sophisticated stationkeeping system and a long riser to connect to the wellhead? Why link surface personnel to seafloor risks? Why increase the complexity of balancing well pressures (without fracturing formations) by adding thousands of feet to the mud column? Why heave and roll on the surface when you can operate from the seafloor?
It’s not that easy, of course, and there are many questions and issues. While fully automated drilling systems are no longer a reach, what about reliability and repairs? How will casing be set and cemented? How will downhole measurements be transmitted to the control center? Cuttings samples? Coring? Well testing? The list of challenges is daunting.
At least one company, Seabed Rig, is committed to developing and demonstrating seafloor drilling technology. Earlier this month, Seabed Rig reached agreement with NASA to create the first autonomous drilling rig. While a lot of work remains, Seabed Rig and other pioneering companies are applauded for their innovative thinking and willingness to challenge conventional practices and wisdom.
Bud's Offshore Energy (BOE) 
Always someone on the ready to design a better mouse trap, apart from the more traditional drilling ends which are clearly pointed out , casing run and cemented ect… My interest is the foundation required to install and sea bed foundation support such a pce of kit x 1000 tons, and the surface equipment necessary to install and connect all the bit. Further all the electrical power will have to be fed on continuously from surface controls and generating vessel by umbilicals to sea bed.
What concern me at once is the type and size of equipment needed to install/ service / repair and move this seabed rig to another location ?