A docking system for microsatellites based on MEMS actuator arrays

Microelectromechanical system (MEMS) technology promises to improve performance of future spacecraft components while reducing mass, cost, and manufacturing time. Arrays of microcilia actuators offer a lightweight alternative to conventional docking systems for miniature satellites. Instead of mechanical guiding structures, such a system uses a surface tiled with MEMS cilia actuators to guide the satellite to its docking site. This paper summarizes work on an experimental system for precision docking of a ‘picosatellite’ using MEMS cilia arrays. Microgravity is simulated with an aluminum puck on an airtable. A series of experiments is performed to characterize the cilia, with the goal of understanding the influence of normal force, picosatellite mass, docking velocity, cilia actuation frequency, interface material, and actuation strategy (‘gait’) on the performance of the MEMS docking system. We demonstrate a 4 cm2 cilia array capable of docking a 41.2 g picosatellite with a 2 cm2 contact area with micrometer precision. It is concluded that current MEMS cilia arrays are effective in positioning and aligning miniature satellites for docking to a support satellite. (Some figures in this article are in colour only in the electronic version)