(1) Autonomy in maritime is not to replace seafarers, the navigation crew is less than 30% of the crew. And crew is negligible OPEX compared to fuel etc. (2) Because the industry is the backbone of global trade, it moves much slower in adopting technology for the sake of technology. However, when there's a simple reliable system that can clear benefit, the adoption happens. So given that there's few[1] lanes in the ocean, you can easily go from one waypoint to the next. (3) Onboard a ship, there's no such thing as breaks. In most cases, you know about a collision or a grounding 12+ minutes in advance. The challenge is in getting the predictions right and abide by the rules of the road. Most advanced LIDAR have 1km range, which is too close, cameras don't see much neither[2].
[1]: there are quite few channels around ports to ease traffic that are one-way. [2]: the resolution is too low to see far out. When using zoom, the stabilization is a nightmare.
As someone who works in the autonomous ship space now and a prior merchant mariner, I agree with a lot of what you state, except for point 1...
In the near term, yes, I agree that people are working to use autonomy to augment the bridge crew (and engine crew and ship owners for that matter). However, in the long run (and there are actually several prototype autonomous vessels on the water today), the ultimate goal is absolutely to eliminate the need for a human crew.
Reasons... The biggest driver is that much of the design of ships is driven by the fact that human crews are embarked. There are too many items to list, but human factors include the ship superstructure (living qarters/bridge/galley/sanitation), freshwater generation, HVAC (a large chunk of energy costs, safety provisions, medical, and on and on. Other drivers are 1.) Human safety, 2.) Asset (ship & cargo) safety, 3.) Litigation avoidance/lower crew/cargo insurance/underwriting - which relate to 1 and 2 (e.g. collisions into other ships, piers, or getting your ship wedged in a canal). Many maritime incidents are the result of human error.
To the naiive, it may seem that autonomous operation at sea is easier than driving autonomously on land. However, the lay person may not realize that ships come in a variety of shaps/sizes and maneuvering abilities (for different functions including ferries, tankers, containerships, taxis, navy vessels, barges, cruise ships, etc.), communicate via complex bridge-to-bridge communications, navigate using a variety of floating/light/radio indicators, and are very sensitive from a stability and structural soundness perspective to weather (seastate, wind, currents, etc), among many other complex constraints. Thanks to inertia and the large absence of "traction", large ships don't stop instantaneously, they have a stopping distance which can be over 4 nautical miles [1] !
Driving cars autonomously is very difficult, but driving ships autonomously is just as difficult, if not more so.
1. https://knowledgeofsea.com/stopping-distance-turning-circle-...
And swimmers!
My office here in Amsterdam is on a canal. All through the summer there are 20-30 swimmers a day. Including one man who every morning swims head-down freestyle the 1km around Prinseneiland.
Does canal swimming seem a bit nuts to you as well?
Actually there are plenty of Single sculls, kayakers, paddleboarders, etc. in most canals in the Netherlands.
But indeed the reaction time you need is still a lot slower than with pedestrians jumping in front of a car.
Going on bigger water is also not easy. Ferries accelerate very quickly when they depart and have priority over small boats.
For bigger boats, you have to assume they cannot see a smaller boat and if they see one, they cannot brake or change course.
Jokes asides, I feel like autonomous driving might technically be made to work by allowing it only on certified roads, with standardized conditions. At that point we might have reinvented trains.
- Roads are cheaper to lay and maintain than rails
- Roads are infinitely more flexible. You cannot walk, bicycle, or hold a parade on a railway track.
On the cheaper I really do not know. Is pouring asphalt cheaper than putting rails? I honestly do not know.
It also might depend on the implementation. I remember a history teacher mentioning that the uk built railwways providing time-limited exploitation licenses for private companies that built them (after x years they became public) and they built a vast network quickly . ( I found this pdf: https://www.campop.geog.cam.ac.uk/research/projects/transpor... about the expansion, but it does not mention the licenses)
In the car case we need to also consider the "wagon", and the fuel cost is outsourced to the customers.
I'm assuming it's supposed to be clever (and it is), but still.... it's gotta get tiring always having to clarify that there isn't a W.
Seriously: this shows to me that people will use any infrastructure that is most convenient/fast for them. If there are highways people will drive. Build public transport and people will use that. Build bike paths and people will bike. If you have canals like Amsterdam, well...
Canals are probably not very fast nor scalable for mass transit, but they may be useful for transporting heavy things.