Vessel Steering Control with Feed Forward Toe-In Correction
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing steering systems for vessels with pivotally arranged propulsion units are sensitive to roll angle and lateral forces, leading to unlevelled roll angles and increased fuel consumption, especially when using single propeller units or reaction rods, which affect performance and maneuverability.
Innovation Solution
A steering control system that includes a feed forward pivot angle correction control block to generate individual correction values for each propulsion unit, adjusting toe-in or toe-out and Ackermann positions based on the unit's position, allowing for adaptive control of roll angles and lateral forces, thereby mitigating unbalanced conditions and optimizing vessel movement.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Stability of the object's composition
If trim planes are used to correct roll angle, then roll angle stability is improved, but fuel consumption increases and performance is reduced
Solution Approach 1:
The system applies preliminary action by pre-calculating and applying individual toe-in/toe-out correction values to each propulsion unit before the vessel actually experiences unwanted roll. The control unit continuously adjusts the angular position of propulsion units based on stored correction values that compensate for mounting tolerances and water flow effects, preventing roll angle deviations before they occur rather than correcting them afterward using trim planes.
2Strength
If reaction rods are used to protect engine mounting, then structural strength is improved, but roll angle stability deteriorates
Solution Approach 1:
The system applies local quality by assigning different correction values to different propulsion units based on their specific positions and mounting conditions. Each propulsion unit receives individualized toe-in/toe-out corrections tailored to its location on the vessel, allowing the system to compensate for the destabilizing effect of reaction rods on specific units without affecting the overall structural protection provided by the rods.
3Device complexity
If fixed Ackermann steering values are used, then steering mechanism simplicity is maintained, but maneuverability precision deteriorates
Solution Approach 1:
The system transitions from static fixed Ackermann values to dynamic, continuously adjusted correction values. The control unit real-time adjusts the angular position of propulsion units based on current vessel speed, direction, and position, allowing the steering system to adapt to varying operational conditions. This dynamic adjustment maintains maneuverability precision across different operating scenarios while keeping the overall control architecture relatively simple.
Data Source
AI summary
Steering control system for a vessel including set of propulsion units including at least two propulsion units pivotally arranged in relation to the hull of the vessel for generating a driving thrust of the vessel in a desired direction, the control system including a steering control instrument for generating input signals for control of a desired route of the vessel a control unit complex controlling the angular position of the propulsion units, the control unit complex being arranged for receiving input signals from the steering control instrument, which input signals represents a general direction of movement of the vessel and thus a general desired angular position of each propulsion unit the control unit complex furthermore containing a feed forward pivot angle correction control block for each propulsion unit, which feed forward pivot angle correction blocks are arranged to generate desired angular positions of the propulsion units by adding a correction value to the general desired angular position of the propulsion units, the correction value including compensation for toe in setting of the propulsion units and/or Ackerman position setting of the propulsion units, and method for operating such a steering control system.