Driverless cars and drones delivering packages at the doorstep are the norms today. In fact shipping is the easiest mode of transport that can be made for unmanned operation. In the days of Alexander and Ceasar ships were built by men on their journey. Ships could be repaired while at sea. During the days of steamships any damage to the ship could be repaired a sea. For this purpose, ships used to carry a large crew. During the last century, crew wages became the most expensive part of shipping cost. It became cheaper to tow the ship to a port and then carry out repair instead of carrying a large crew and repair at sea. At present, carrying no crew can save a large proportion of shipping cost. Experiments were going on in Norway for a long time for an Autonomous ship. Recently they have successfully tested a model that can be operated from shore. This ship need not carry any crew at sea. Sixty percent of the sea miles travelled are in the open sea where there are few ships to encounter. Anti collisionequipments are already available. Crew is required only in the port. Crew can board the ship at the fairway buoy. Crew is also required during pilot age or transit through canals or locks. The quantum of goods transported through ships is unlikely to come down.
The only worry at present is safely of the ship not through collision or bad weather but by hijacking by cyber criminals. They can hijack the ship at sea and ask for ransom. Or they can take over the ship and take to a port of their choice and steal the cargo.
There is going to be huge saving in ships construction. There is no need for crew quarters, galley and safely boats. Cost of the ships will come down. Cost of ships operation will come down. Cost of insurance also will come down. The cost of entire shipping will come down and this will eventually benefit the consumers.
At the end of WW II unmanned vessels were designed for mine-sweeping operations. The vessels were controlled remotely from a nearby vessel. The purposes of the vessels were to save human life from dangerous operations such as mine sweeping. The purpose of automation in commercial shipping is to reduce cost to the consumer. Cost can be reduced for ship building, ship operation and marine insurance.
Sail drones was invented by Richard Jenkins a British engineer. It has got a tri-maran hull and sails plus solar panels. Such vessels are used for weather monitoring navigational guidance. They are also used for hydrographic survey and military target practice.
Unmanned vessels were recently used to locate lost aircrafts.