Underwater Vehicle Attitude Control via Dynamic Cable Length Adjustment
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing underwater vehicle systems for nuclear reactor inspections face difficulties in maneuverability due to external forces from cables, which are not adequately addressed by current cable assist devices that fail to consider regular navigation forces.
Innovation Solution
A system for attitude control of underwater vehicles that includes a thruster, an assist device with cable handling equipment, a cable attachment-to-attachment distance detection unit, and a control unit that determines the amount of cable to wind up or let out based on detected attachment-to-attachment distance, thereby mitigating the effects of external cable forces.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of operation
If cable assist device is used to handle cable, then cable management is improved, but external force from cable still affects underwater vehicle maneuverability
Solution Approach 1:
The system performs preliminary calculation of cable length based on attachment-to-attachment distance before the underwater vehicle moves. The control unit determines the required cable length in advance using the relationship L = √(h² + d²), where h is vertical distance and d is horizontal distance, allowing the cable to be properly managed before external forces become problematic during vehicle operation
Solution Approach 2:
The system continuously monitors the attachment-to-attachment distance between the underwater vehicle and assist device, and uses this feedback to dynamically adjust cable length calculations. The control unit receives real-time distance data and recalculates required cable length to maintain optimal cable tension and minimize external forces on the vehicle during movement
2Device complexity
If cable length is fixed, then cable handling is simplified, but underwater vehicle navigation precision deteriorates
Solution Approach 1:
The system transitions from fixed cable length to dynamic cable length adjustment. The control unit continuously calculates the optimal cable length based on real-time attachment-to-attachment distance measurements, allowing the cable length to adapt dynamically to the underwater vehicle's position changes, thereby maintaining both simplified handling and high navigation precision
3Reliability
If cable tension detection is used to detect cable entanglement, then cable status monitoring is improved, but external force effects on vehicle movement are not eliminated
Solution Approach 1:
Instead of merely detecting cable entanglement after it occurs through tension monitoring, the system performs preliminary prevention by calculating the required cable length in advance based on attachment-to-attachment distance. This proactive approach ensures the cable is properly tensioned before the vehicle moves, preventing external force issues before they arise
Solution Approach 2:
The system uses real-time feedback from attachment-to-attachment distance measurements to continuously adjust cable length calculations, providing ongoing monitoring that prevents cable entanglement and external force issues rather than merely detecting them after occurrence
Data Source
AI summary
A system for attitude control of an underwater vehicle 20 of the present invention includes an underwater vehicle 20 with a thruster 65, an assist device 10 that is coupled to the underwater vehicle 20 with a cable 1 and has cable handling equipment 2 and a thruster 58, a cable attachment-to-attachment distance detection unit 50 that detects distance between a cable attachment of the underwater vehicle 20 and a cable dispenser of the assist device 10, and a control unit 32 that previously stores the relationship between the attachment-to-attachment distance and cable length including a predetermined amount of slack and determines the amount of cable to be wound up or let out based on the cable length associated with the detected attachment-to-attachment distance.