Development of a deployable baffle for CubeSat star trackers actuated by shape memory alloy wires

In order to address the presence of stray light within the optical system of star trackers, it is necessary to equip the star trackers with a baffle, the function of which is to suppress stray light in an effective manner. Due to the compact size of CubeSats, star trackers cannot be used in CubeSats. To address this challenge, a deployable baffle driven by shape memory alloys (SMAs) is proposed as a solution. The deployable baffle is locked by steel balls when it is folded, and is unlocked by a shape memory alloy actuator. Subsequent deployment of the baffle is driven by the compressed conical springs. The prototype is developed and the response time test is conducted. The results show that the deployable baffle can be deployed within 1.0s. It demonstrates its potential as an attractive alternative technology.