B-Spline Spacecraft Attitude Control for Command Data Compression
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing spacecraft attitude control systems face challenges in efficiently managing large datasets of time-tagged commands required for attitude guided maneuvers, leading to storage and transmission bottlenecks.
Innovation Solution
The implementation of a B-spline interpolator in the spacecraft attitude control system, which downsamples attitude trajectories, transmits reduced command sets, and uses interpolation to reconstruct commands at the attitude control system's update rate.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If traditional attitude control systems use full-resolution time-tagged command datasets, then maneuver precision is maintained, but storage requirements and transmission bandwidth increase significantly
Solution Approach 1:
The patent extracts only the essential information needed for maneuver execution by representing attitude trajectories using B-spline basis functions with a limited set of control points and coefficients. Instead of storing complete high-resolution command datasets, the system stores only the compact mathematical representation (control points and B-spline coefficients) that can be used to reconstruct the full trajectory when needed, thereby dramatically reducing storage requirements while preserving maneuver precision.
Solution Approach 2:
The patent transforms the representation parameters of attitude commands from discrete time-tagged values to continuous B-spline mathematical parameters. By changing the parameterization method from storing numerous individual command points to storing a compact set of B-spline control points and coefficients, the system achieves efficient data compression while maintaining the ability to generate high-resolution commands for precise maneuver execution.
2Measurement precision
If spacecraft systems store and transmit complete attitude command trajectories, then control accuracy is preserved, but communication bandwidth and processing load increase
Solution Approach 1:
The patent extracts the essential maneuver information into a compact B-spline representation that can be transmitted efficiently. Instead of communicating complete high-resolution command trajectories, the system transmits only the B-spline control points and coefficients, which are then used onboard to reconstruct the full attitude trajectory at the required update rate, thereby improving communication efficiency without sacrificing control accuracy.
Solution Approach 2:
The patent performs preliminary computation of the B-spline representation on the ground before transmission. By pre-processing the attitude trajectory into its compact B-spline form and preparing the control points and coefficients in advance, the system reduces the real-time processing burden on the spacecraft and enables efficient communication of maneuver data, while the actual high-resolution command generation occurs onboard using the pre-computed parameters.
3Stability of the object's composition
If attitude control systems process high-resolution command sequences, then maneuver smoothness is achieved, but computational resources and processing time increase
Solution Approach 1:
The patent replaces the mechanical approach of storing and processing large sequences of discrete command values with a mathematical substitution using B-spline basis functions. Instead of mechanically handling numerous individual command points, the system uses continuous mathematical functions parameterized by a small set of control points and coefficients, thereby reducing computational complexity and resource requirements while maintaining maneuver smoothness through the inherent continuity properties of B-splines.
Solution Approach 2:
The patent changes the computational parameters from processing many discrete command values to manipulating a small number of B-spline control points and coefficients. This parameter transformation simplifies the computational task, as the system only needs to update and process the compact set of B-spline parameters rather than handling entire high-resolution command sequences, thereby reducing device complexity while preserving maneuver quality.
Data Source
AI summary
A method, apparatus and system for controlling an attitude of a spacecraft, the spacecraft including an attitude control system operatively associated with a ground-based spacecraft control system. According to an exemplary embodiment, the spacecraft attitude control system uses a B-spline interpolator for commanding the spacecraft. The methods and systems disclosed herein can be implemented in, for example, executable machine code and/or integrated circuit hardware.