Marine Propulsion Control Using Funnel Boundaries for Obstacle Avoidance
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing marine vessel propulsion control systems face challenges in autonomously navigating and avoiding obstacles in complex marine environments, particularly due to limitations in degrees of freedom and external factors like currents and waves, which can lead to collisions.
Innovation Solution
A propulsion control system that utilizes proximity sensors and a controller to calculate a funnel boundary based on user input and object proximity, adjusting propulsion to maintain a buffer distance and avoid collisions, while allowing for semi-autonomous or autonomous operation to ensure safe navigation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If the propulsion system operates with full authority and velocity, then productivity and speed are improved, but the risk of collision with objects increases
Solution Approach 1:
The system continuously receives proximity measurements from sensors about objects in the environment and uses this feedback to dynamically adjust propulsion authority. The controller monitors object positions and modifies velocity commands in real-time based on proximity data, enabling the system to maintain high productivity when safe while automatically reducing speed or altering course when objects are detected, thus resolving the contradiction between speed and collision avoidance
Solution Approach 2:
The propulsion system transitions from static full-authority operation to dynamic adaptive control. The system dynamically adjusts propulsion parameters including velocity limits and authority based on real-time environmental conditions and object proximity. This dynamic adjustment allows the system to optimize productivity in open spaces while automatically prioritizing safety near objects, effectively resolving the contradiction between speed and collision risk
2Reliability
If autonomous control is implemented to avoid collisions, then reliability is improved, but device complexity increases
Solution Approach 1:
The controller is designed as a multi-functional device that performs both traditional propulsion control and autonomous collision avoidance functions. By integrating sensor data processing, object tracking, velocity limiting, and propulsion command generation into a single controller, the system achieves autonomous safety features without proportionally increasing overall device complexity. The controller leverages existing propulsion system components while adding intelligent control algorithms, making the autonomous functionality more accessible
3Reliability
If velocity limiting is applied to maintain buffer distance, then collision avoidance is improved, but productivity decreases
Solution Approach 1:
The velocity limiting mechanism is dynamic rather than static. The system continuously adjusts velocity limits based on real-time proximity measurements and object positions. When no objects are present or distances are large, the system maintains or restores full propulsion authority for optimal productivity. When objects are detected within critical distances, velocity limits are temporarily applied to maintain safe buffer distances. This dynamic approach ensures productivity is maximized whenever safe while automatically prioritizing safety when needed
Data Source
AI summary
A method of controlling a propulsion system on a marine vessel includes receiving proximity measurements describing locations of one or more objects with respect to the marine vessel, receiving a command vector instructing magnitude and direction for propulsion of the marine vessel with respect to a point of navigation for the marine vessel, and then determining a funnel boundary based on the command vector. When an object is determined to be within the funnel boundary, a propulsion adjustment command is calculated to move the marine vessel such that the object is no longer in the funnel boundary. At least one propulsion device is then controlled based on the propulsion adjustment command.