Session
Pre-Conference Workshop Session I: Advanced Concepts I
Location
Utah State University, Logan, UT
Abstract
Payload operations for small satellites are often impacted by the need to allocate time for modifying the attitude to perform power generation or orbit maneuvering. A typical small satellite design would consist of a single rigid body with body-mounted solar cells, making the power generation subject to the spacecraft’s attitude. Often to achieve the high power generation that is required to enable the payload function, the attitude must be specifically set to maximize the solar cell area facing the Sun, which typically means diverting it from an attitude that is useful for payload operations for some period of time. At the scale of modern global constellations, these downtimes in the payload operation schedule can greatly reduce the overall capability of the system. By including deployable, articulating solar arrays in the design of small spacecraft, array pointing can be decoupled from the mainpayload pointing operations. With these pieces decoupled, payload operations can proceed uninterrupted while the articulating arrays ensure sufficient power generation. In this paper, the dynamic equations of the multibody system are derived, and guidance, navigation, and control (GNC) considerations are presented for achieving decoupled attitude and articulation objectives. Results from simulation of a sample mission show that agile target tracking attitude maneuvers can be performed together with array solar tracking with negligible impact on overall payload pointing performance.
Guidance, Navigation, and Control for Agile Small Spacecraft with Articulating Solar Arrays
Utah State University, Logan, UT
Payload operations for small satellites are often impacted by the need to allocate time for modifying the attitude to perform power generation or orbit maneuvering. A typical small satellite design would consist of a single rigid body with body-mounted solar cells, making the power generation subject to the spacecraft’s attitude. Often to achieve the high power generation that is required to enable the payload function, the attitude must be specifically set to maximize the solar cell area facing the Sun, which typically means diverting it from an attitude that is useful for payload operations for some period of time. At the scale of modern global constellations, these downtimes in the payload operation schedule can greatly reduce the overall capability of the system. By including deployable, articulating solar arrays in the design of small spacecraft, array pointing can be decoupled from the mainpayload pointing operations. With these pieces decoupled, payload operations can proceed uninterrupted while the articulating arrays ensure sufficient power generation. In this paper, the dynamic equations of the multibody system are derived, and guidance, navigation, and control (GNC) considerations are presented for achieving decoupled attitude and articulation objectives. Results from simulation of a sample mission show that agile target tracking attitude maneuvers can be performed together with array solar tracking with negligible impact on overall payload pointing performance.
