Micro star tracker with a curved vane for a short baffle length and sharp stray light attenuation

Area of Science:

• Aerospace Engineering
• Optical Engineering
• Spacecraft Instrumentation

Background:

• Star trackers are crucial for spacecraft navigation.
• Stray light significantly degrades star tracker performance and accuracy.
• Existing baffle designs often compromise on length or stray light attenuation.

Purpose of the Study:

• To develop a micro star tracker baffle with curved vanes.
• To achieve a short baffle length and sharp stray light cutoff.
• To improve star tracker sensitivity and accuracy.

Main Methods:

• Mathematical derivation of curved vane geometry using ray-tracing.
• Fabrication of three micro star tracker baffles with varying curved vane configurations (single and double).
• Experimental validation of stray light attenuation and performance comparison with straight vane designs.

Main Results:

• Curved vane design enables complete stray light cutoff with fewer vanes and shorter baffle length.
• Fabricated baffles demonstrated effective stray light reduction for a 22° field of view.
• The proposed micro star tracker achieved an accuracy of 1.288 arcsecond, a 20.6% improvement.

Conclusions:

• The curved vane baffle design is a highly effective solution for stray light suppression in micro star trackers.
• This design facilitates more compact and sensitive spacecraft navigation systems.
• The mathematical approach ensures optimal stray light reflection, enhancing overall performance.