A Rapid Self-Alignment Strategy for a Launch Vehicle on an Offshore Launching Platform

Area of Science:

• Aerospace Engineering
• Navigation Systems
• Control Systems

Background:

• Offshore launching platforms experience motion and swaying, impacting launch vehicle self-alignment accuracy.
• Strapdown Inertial Navigation Systems (SINS) are crucial for attitude determination but susceptible to platform dynamics.
• Existing alignment methods may not fully leverage available SINS data under dynamic conditions.

Purpose of the Study:

• To propose a rapid self-alignment strategy for launch vehicles on offshore platforms.
• To enhance self-alignment accuracy by mitigating the effects of platform motion and swaying.
• To enable fully autonomous initial attitude determination for launch vehicles.

Main Methods:

• Developed a strategy combining anti-swaying coarse alignment (ASCA), backtracking navigation, and reverse Kalman filtering.
• Stored and utilized SINS data for both forward and backtrack self-alignment processes.
• Designed a cycle-index control function for backtracking navigation and an error model for reverse fine alignment.

Main Results:

• The proposed strategy effectively compensates for attitude errors after forward navigation cycles.
• Numerical simulations demonstrated improved alignment accuracy and reduced alignment time.
• Maximized the utilization of SINS data during the alignment process.

Conclusions:

• The novel self-alignment strategy significantly enhances accuracy and efficiency.
• This technology offers a viable autonomous alternative to complex optical aiming systems.
• Enables reliable initial attitude determination for launch vehicles prior to launch.