System Components & Functions Flashcards
7 cards from real DPO practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 7 System Components & Functions flashcards as text
What is the primary function of a gyrocompass in a DP system?
Answer: Provide a stable heading reference independent of magnetic variation
A gyrocompass provides a true north heading reference that is unaffected by magnetic variation or deviation, making it essential for accurate DP heading control.
In a DP system, what does the term 'model' refer to in the context of the mathematical model?
Answer: A mathematical representation of the vessel's response to forces
The mathematical model in a DP system represents how the vessel responds to environmental forces and thruster outputs, allowing the controller to predict and correct vessel motion.
Which component in a DP system is responsible for converting electrical power to rotational force on the propeller shaft?
Answer: Variable Speed Drive (VSD)
A Variable Speed Drive (VSD), also called a frequency converter, controls the speed of the electric motor driving the propeller by varying the frequency and voltage of the power supply.
What is the role of the Kalman filter in a DP control system?
Answer: Separate useful position signals from noise and sensor errors
The Kalman filter is a mathematical algorithm that processes noisy sensor measurements to produce optimal estimates of vessel position, velocity, and heading.
A differential GPS (DGPS) system improves positioning accuracy by:
Answer: Applying corrections from a known fixed reference station
DGPS uses correction signals broadcast from a fixed reference station whose exact position is known, removing common-mode GPS errors and improving accuracy to sub-meter levels.
What is the function of an Uninterruptible Power Supply (UPS) in a DP installation?
Answer: Supply bridge equipment with conditioned power during transient outages
A UPS maintains power to critical DP computers, sensors, and control consoles during brief power interruptions, preventing loss of position during generator switching.
Which type of thruster produces thrust in a single fixed direction and relies on vessel rotation for maneuvering?
Answer: Fixed-pitch propeller
A fixed-pitch propeller produces thrust only ahead or astern; lateral maneuvering requires hull rotation, making it less versatile for DP than azimuth or tunnel thrusters.