Modern ship automation and control
Courses by Topic
This, as may be appreciated, is of great relevance to the direction in which ships of the immediate future are expected to operate. Great amounts of a wide variety of data on board a ship are required to be communicated. In fact, a good many onboard systems are to be meant to collect and present data to the crew as aids for timely decision making during the ship’s day to day operation. With great technological developments in the field of sensors, communication, and data analytics (the systematic computational analysis of data or statistics), the designing of “connected vessels” is on the rise, with communication infrastructures that bring forth the implementation of a range of modern applications, based on the available shipboard data.
Over and above the extant regulatory practices – two-way voice communication (by radio or satellite); automatic identification system(AIS); long-range identification and tracking(LRIT); vessel traffic services(VTS) and port arrival notifications, latest voluntary operational applications are getting in vogue.
The technological advancement made in the domain of ship connectivity, is expected to provide a range of the following new opportunities for the players in the maritime community – Shipowners and Operators: To improve the cost-efficiency and bring down the downtime due to smarter vessels which are equipped with advanced ICT and sensor systems, Yards and ship equipment vendors: To design and sell smarter and technologically advanced vessels to the ship owners, Maritime Authorities and Regulators: By way of having the regulations and standards modernized and updated, and having better control in improving maritime safety and environmental conservation, Charterers and Cargo owners: To get better and qualitative insights into the whereabouts and condition of the cargo. This will be advantageous in optimizing cargo logistics and assist in verifying compliance with the charterer’s terms and conditions.
Cloud computing is an outsourcing of computer programmes. By utilizing cloud computing, users are able to access software and applications from wherever they need, while it is being hosted by an outside party, in the cloud. This implies, the users do not have to worry about issues like storage of own data (because you are not required to manage hardware and software) and power. The users can simply have access to and use the end result. Some of the world’s largest companies have moved their applications to cloud, of course after rigorously testing the security and reliability of the infrastructure.
Cloud computing is a general term for anything that involves delivering hosted services over the internet. A cloud service has three characteristics that differentiate it from traditional hosting. It is sold on demand, typically by the minute / hour; it is elastic, i.e. an user can have as much or as little of a service as desired at any given time; and the service is fully managed by the service-provider. The customer needs only a personal computer and internet access. Cloud computing, in effect, is basically an internet-based computing.
Various usage-areas relating to cloud computing – Ship / fleet management: Software application support is designed to meet all the demands placed on the crew of a ship / fleet of ships, enabling the crew to plan and execute the assigned tasks. Maintenance management -software application support that allows the planning and execution of ship maintenance procedures, spare parts / stores / materials management of each ship and the fleet. Document management – software application support that helps in managing documents (document editing, archives, distribution and control of document versions). This function enables accessing any document.
Onboard and shore-based application services that use data from navigation, machinery, and other onboard equipment, including the ones listed below, are increasingly common. Automation and control system is a fully integrated systems covering many aspects of the ship operation that includes the propulsion plant operation, power management operation on the auxiliary engines, auxiliary machinery operation, cargo on-and-off-loading operation, navigation and administration of maintenance and purchasing of spares.
Weather Routeing is the art of achieving a safe and economic passage across an ocean, taking in to consideration all available meteorological and oceanographical factors.
The purpose of ship’s routeing is to – Navigate the vessel on the best route that avoids the worst of weather conditions, Avoids area of fog or ice, Take advantages of currents, less fuel consumption, Reduction of heavy weather damages and Less passage time.
The ship speed and route is best not only to be decided by commercial and contractual considerations but also using data on sea condition, sea currents, water depth and wind characteristics. The optimal speed distribution along the route can be calculated in advance, if a weather forecast is available. These techniques are used by weather routing service providers as part of their ship modeling and analysis.
Weather routing service can direct the ship away from sea areas where such weather conditions exist with the likelihood of damage and increased fuel costs. Heavy rolling with a beam sea can result in significant damage to both the ship (racking stresses) and the cargo, particularly if it is carried on deck so it may be necessary to alter course lengthening the distance.
Weather routing service can use long-range weather forecasts to route the ship away from these heavy beam sea conditions, optimising the distance and time travelled. In the case of extreme heavy weather conditions such as Tropical Revealing Storms (TRS) or hurricanes, it may be necessary to make substantial changes to the intended track resulting in a much larger distance travelled. Weather routing services with their up-to-date and accurate information of the direction of the storm can direct the ship on the safest and shortest route to avoid dangerous sea conditions.
Autopilot is one of the most important equipments used in ships. Autopilots are not just used to lead the ship on a desired trajectory, but also to raise the safety level of the journey and control the ship economically. An optimal autopilot can shorten 3–5% length of the journey and therefore, reduce the fuel consumption, especially in bad weather conditions. Poor directional stability causes yaw motion and thus increases fuel consumption. Autopilot has a big influence on the course keeping ability.
The best autopilots today are self-tuning, adaptive autopilots. Finding the correct autopilot parameters suitable for the current route and operation area will significantly reduce the use of the rudder and therefore reduce the drag. Finding the correct parameters or preventing unnecessary use of the rudder gives an anticipated benefit of 1-5%.
Adaptive Autopilot System with Minimum Propulsive Energy Consumption – It is well-known that auto pilots now used on many ships cause yawing with a prolonged periodicity which has an unfavourable effect on propulsive energy. Energy loss during navigation of a ship is closely related with yaw motion and can be reduced by suitable steering. The correct parameters or preventing unnecessary use of the rudder gives an anticipated benefit of up to 4% saving in fuel consumption for all ships.
Optimum use of rudder and heading control systems (autopilots) – There have been large improvements in automated heading and steering control systems technology. Whilst originally developed to make the bridge team more effective, modern autopilots can achieve much more. An integrated Navigation and Command System can achieve significant fuel savings by simply reducing the distance sailed “off track”. The principle is simple; better course control through less frequent and smaller corrections will minimize losses due to rudder resistance.
The trim can have a significant impact on a vessel’s energy demand for propulsion during sailing. The most efficient trim for a particular ship depends on its design, operational draft and speed. Optimum trim refers to a ship’s trim under which the required propulsive power is minimal for the specific operational speed and draft of the vessel.
A ship’s resistances and its trim are closely related to each other. This is due to the fact that trim could change parameters that impact the hydrodynamic performance of a ship. The high impact of trim on ship performance is well known in particular for container ships and RoRo vessels. Large fuel savings are claimed due to changes to the ship trim. On fast container ships and RoRo vessels, there is much to be gained by introducing the correct (optimum) trim. However, a reduction in fuel consumption due to changes to trim might be achieved even on tankers and bulk carriers.
Most ships are designed to carry a certain amount of cargo at a designated speed, consuming a certain amount of fuel under a specified trim condition. Loaded or ballast, trim has a significant influence on the resistance of the ship through water. Therefore, optimizing the trim can deliver significant savings.
Ship trim optimization has gained enormous momentum in recent years being an effective operational measure for better energy efficiency to reduce emissions. Ship trim optimization principles are based on the fact that ship experiences different (more or less) resistance through water for the same speed and draft depending on its trim. Ship trim optimization simply advocates selecting the trim condition for minimum resistance. The resistance through water is then proportional to the amount of required power and governs the required fuel burn rate.
In shipping industry, there has been a continuous demand and interest in ship performance monitoring (SPM) overall and also the monitoring of ship’s major operations or machinery systems. When high fuel prices and air emissions control take centre stage in the marine industry, the urge to increase a ship’s energy efficiency using SPM is normally higher. Additionally, the more sophisticated engines with their recent developments in the combustion process (with thermal efficiencies reaching up to 52%), waste heat recovery systems (with reported benefits of 10% extra energy efficiency), use of emission reduction technologies such as SOx scrubbers and the persistent issues of variable quality fuel; all dictate a closer monitoring on the fuel engine itself, and exhaust system as a matter of best practice. The propulsive (hull and propeller) efficiency can be improved significantly by reducing hull and propeller surface roughness. Frictional resistance forms about 70-90% of the total resistance of a ship for bulk carriers and tankers (approx. 50% for cruise liners and container vessels) and is directly affected by hull roughness, which in turn is affected by fouling. Keeping the hull and propeller smooth and free from fouling is therefore essential for optimal ship energy efficiency.
A modern automation and control system is a fully integrated systems covering many aspects of the ship operation that includes the propulsion plant operation, power management operation on the auxiliary engines, auxiliary machinery operation, cargo on-and-off-loading operation, navigation and administration of maintenance and purchasing of spares.
Today’s modern ships have many inbuilt systems supported by IT resources that feature the latest advances in ship technology, such as propulsion system, navigation system and other systems on the command bridge, ship’s cargo control and manipulation system, system of monitoring and management of fire and flooding protection system, electric power system, ship administration system, etc. The IT resources implemented in ship systems are increasingly taking on central functions in the creation, monitoring, control and implementing of maritime processes. Process modules, called control modules or controllers, are installed in ship systems. Their role is to monitor and control pre-defined operational parameters of the system they are installed in. Several dozens of autonomic process modules have been implemented on big ships.
The Internet of Things revolves around increased machine-to-machine (M2M) communication and is built on cloud computing and networks of data-gathering sensors. Beyond our daily lives at home, this concept is also becoming widely used in the industrial sector and has been dubbed the Industrial Internet of Things (IIoT). Now M2M technology allows us to manage and monitor equipment remotely and address problems in a timely manner, which also translates to cost savings.
A variety of M2M solutions are available that can help diagnose and fix equipment issues, including remote desktop that allows users to manage the machine/process remotely as if they were standing in front of a human-machine interface (HMI) connected to a supervisory control and data acquisition (SCADA) system.