Solar Probe Plus (SPP) wrap around automated testing

Abstract

The Solar Probe Plus (SPP) mission, under NASA's Living with a Star program, will fly a spacecraft (S/C) through the sun's outer corona. The mission will gather data on the processes of coronal heating, solar wind acceleration, and production, evolution and transport of solar energetic particles. The spacecraft has an Electrical Power System or EPS that has to undergo testing before delivery to the spacecraft for integration and testing. The specific unit to be delivered is called the Power System Electronic box or PSE. The PSE relies on a novel S/A control algorithm which autonomously positions the wings to optimize the thermal load while maintaining adequate electrical power. A Wrap Around Automated Testbed (WAAT) containing various Ground Support Equipment (GSE) has been designed to test the PSE in real-time. The major components of the Testbed consist of a dynamic solar array simulator (SAS); A Battery Simulator to emulate the spacecraft flight battery; An EPS emulator to control command and telemetry to the PSE. This EPS emulator also provides a fast serial link for incident radiant flux on the S/A wings for any wing angle, S/C attitude and shadow condition during any point in the mission computed via a Simulink model to the SAS based on PSE telemetry. The EPS emulator will also provide any necessary loads, power supplies and temperatures and A script engine that will allow communication between all GSE and provide complete automation. This WAAT provides the user the ability to test the PSE or any other Unit Under test including board or slice level designs by having command and telemetry specific to that particular GSE. Each GSE then becomes part of an entire Testbed completely under automated control by tying it to a single script engine on a server. With the exception of the script engine each GSE has a PXI controller and is using PXI modules to accomplish various tasks including controlling and communicating with multiple Digital Signal Processors (DSPs). The WAAT can travel with the PSE or the UUT to automate the process for environmental testing before delivery to the spacecraft. The WAAT can also be used for back up testing in the event any anomalies that occur during spacecraft integration or flight.