25 years ago, the CSRI Elektropribor proposed to use a gimballess electrostatic gyroscope (ESG) in spacecraft attitude reference systems. The system called BIS-EG passed the first flight tests in 2004. By 2013, 20 such systems had been manufactured for three types of spacecraft. The flight tests and regular operation of BIS-EG revealed a number of limitations inherent in them; at the same time, calibration methods were developed and tested and the ways of improving the system accuracy and reliability were identified. Гироскопия и навигация. Том 29. №3 (114), 2021 79 Электростатический гироскоп в системах ориентации космических аппаратов As a consequence, BIS-EG was upgraded for the next generation spacecraft, and it is still in operation. Its distinctive features are higher reliability, the gyroscope of greater stability, and the possibility of in-flight calibration of its drift model. The next modification of the BIS-EG, which is under development now, must meet the requirements for higher accuracy characteristics and the need to work in the unpressurized spacecraft compartment. The stages and methods for improving the gimballess ESG and BIS-EG family systems are described, as well as the results of their operation in accordance with their purposes in different types of spacecraft.
