The maritime industry makes a significant contribution to the globalized economy. One of the most important parts of the maritime industry is transport. Maritime transport by ships is the dominant means of transport for industrial products and food. Modern ships are increasingly automated. A characteristic feature of automation systems is the use of distributed monitoring and control systems with large distances between field devices and controllers. Among many methods of signal transmission, both in measurement and control, the dominant role in related to continuous signals is played by the two-wire 4-20 mA current standard. Despite its advantages, this standard has limitations mainly due to one-way transmission of information representing one measurement quantity. Programmable transducers are an alternative to analogue solutions. This carried out research concentrates on the full assessment of the properties of the considered methods of information transmission used so far with particular reference to the two-wire 4-20 mA standard. This assessment also takes into account the negative factors characterizing the sea-going ships, such as environmental conditions or problems resulting from the use of an isolated power grid. Additionally, a description of the available digital methods used for communication in ship automation systems will be presented. Firstly, description will be provided for HART protocol (Highway Addressable Remote Transducer), Foundation Fieldbus, Profibus PA and Modbus as communication protocols adopted by modern smart transducers as alternatives for classical analogue 4-20 mA transducers. Moreover, serial communication interfaces such as RS232, RS422 and RS485 will be discussed as means of communication between automation stations. In order to demonstrate the positive contribution for smart transmitters in measurement and control process, an experimental research has been conducted at the laboratories of Gdynia Maritime University, results of which will be discussed in detail in this article. Eventually, illustration will be provided for tank level measurement systems on a commercial ship as an example for measurement and control system mainly based on classical 4-20 mA current signal. Description will be provided for the problems associated with the system and their causes. Based on the conducted discussions, there will be recommendations of suggested solutions for such problems.

The purpose of this article is to provide an overview of possible solutions to improve the performance of measurement and control processes in maritime engineering applications. This improvement can be basically provided by adopting techniques to enhance the reliability of measurement/control systems based on the 4–20 mA analogue standard. This aspect will be discussed through a Simscape Simulink model illustrating methods of noise and ground loops elimination for pressure measurement of a 4–20 mA current loop in the tank level measurement system on a bulk carrier commercial ship. Alternatively, improved measurement and control processes can be rendered by utilizing smart transmitters based on wired hybrid analogue–digital (Highway Addressable Remote Transducer (HART)), wired digital (Foundation Fieldbus (FF)) or wireless (wireless HART) communication protocols. A brief theoretical description of these protocols will be presented in this article. As an example of using smart transmitters, a simulation-based case study will analyze the possible options to implement non-intrinsically safe as well as intrinsically safe FF models for the tank level measurement system on a bulk carrier commercial ship. Conclusions obtained through analysis of the simulation results will characterize the behavior of FF segments in safe as well as explosive hazardous areas, highlighting the characteristics of field barriers and segment protectors used in conjunction with the HPTC (High-Power Trunk Concept) intrinsically safe model.

The purpose of this article is to provide an understanding of possible techniques through which a H1 31.25 kbps Foundation Fieldbus Manchester coded signal can be modulated or demodulated. This understanding will be rendered through MATLAB and SIMULINK models, simulating both ideal and practical as well as noiseless and noisy conditions during the modulation/demodulation process. The simulation models will differentiate between the modulation methods adopted to generate ideal rectangular as well as practical trapezoidal waveforms for the Manchester coded signal. The analysis of the simulation results will describe the mechanisms through which distortion induced by additive white Gaussian noise can be eliminated during the demodulation process either by using recursive filters, such as a Kalman filter, or by calculating wave energy levels in specific time intervals.

The use of wireless technology in common marine engineering applications as a medium for data transaction in measurement and control systems, is not as popular as it should be. This article aims to demonstrate the advantages of using wireless technology in maritime engineering applications through a proposed Wi-Fi based wireless system dedicated to performance and safety monitoring in marine cargo cranes. The system is based on some concepts that were suggested in the earlier literature to perform authenticated data transmission from multiple sensors through using both the ESP-NOW protocol and the WebSerial remote serial monitor. The introduced system will be integrated with an already installed system in order to render the means for implementing effective principles in automation and control engineering, such as functional safety and predictive maintenance. Additionally, this article will highlight the economic efficiency of adopting wireless technology instead of cabling as a medium for data transaction in measurement and control systems in marine engineering applications such as cargo cranes.