The results of preliminary studies using a spherical proof mass in the LISA mission are given. These include the acceleration disturbance performance, methods for controlling and calibrating a spinning sphere, system considerations, the possibility of using the spinning reference as a precision gyroscope to improve the attitude control, and a preliminary design with a spherical proof mass.
Benjamin Lange, Benjamin Lange,
"Preliminary studies of spherical proof masses in LISA drag-free satellites", Proc. SPIE 4856, Gravitational-Wave Detection, (26 February 2003); doi: 10.1117/12.458562; https://doi.org/10.1117/12.458562