Automatic logging of data – Setting up a system where the continuously logged data are collected on disks or in a data base and transferred to shore for analysis and used in the performance evaluation
Automation of data handling – A shipping company with a large number of vessels in the fleet would try to establish some sort of automation in the evaluation of the different ship’s performances to avoid time consuming manual analysis work. Data handling routines to avoid drift in timing of the signals, eliminating noisy signals and setting up boundaries for valid performance evaluation results are achieved
Data filtering – The models used in the performance system are designed to handle the data logged on board the ship i.e. to handle the limitations in the number of data and the various logging intervals. This requires more or less simplicity in the models depending on the available signals. The models used are often not able to handle events where the ship is in manoeuvring situations or operations in heavy weather. In cases where these situations are included the model fails and this will lead to large scatter in the performance evaluation results. Continuously logged data with a short logging interval will contain data with all kind of operational conditions. A filtering routine to reduce scatter and improve the reliability of the performance evaluation result is needed
Performance evaluation results – The performance of the ship is determined by a performance index. Over time this index will change with a certain rate depending on the operational conditions of the ship. Examples of performance indices are: One relating to the ships speed, one to the torque measurement on the propeller shaft and a third describing the added roughness of propeller and hull.