Operating real equipments with fully simulated On Board Computer

Transcription

1 Operating real equipments with fully simulated On Board Computer SimEFM, a new validation infrastructure SESP ESTEC 25/27 September D. Chatelais, W. Gonzalez ACE83 Satellite FVI

2 Introduction In Functional Validation approach, tests involving real equipments use large hardware test benches With a hardware model of the OBC and its associated EGSE Direct impact on cost, schedule, and processes Alongside, numerical simulators are now widely used Fully representative numerical model of the OBC Emulation of the OBC processor Low cost and versatile systems Numerical simulators performances make possible a new configuration : SimEFM A mix of numerical simulator and some H/W interfaces Operating real equipments with fully simulated OBC Date - 2

3 Numerical Simulators Based on a fully representative model of the OBC Run exactly the same Flight Software (FSW) as the one used on the real computer, taken as a binary image file Full numerical validation infrastrucutre (AOCS part) Model#x (Actuators) CCS TC TM OBC model + Processor emulator Dynamic & environment models Model#y (sensors) High performance and excellent fidelity Faster than real-time From FSW validation up to space operations validation Low cost and versatile systems, easily deployed Available for a large number of people involved in validation Date - 3

4 Hybrid infrastructures Dedicated to tests with real equipments Characterization test benches, with HW I/F to equipment Large hardware test benches Avionic Test Bench, flatsat, EFM/PFM benches Include, at least, one real OBC and its associated EGSE (TM/TC ) Additional SCOE to interface equipments (stimulators ) Coupled with simulations, for closed-loop (HIL) tests Use the same models and simulation infrastructure as for numerical simulator Real equipments Hybrid infrastructure Real (actuator) HW I/F (acquisition) Model#x (Actuators) CCS TC TM TM/TC SCOE Real OBC Dynamic & environment models Real (sensor) HW I/F (stimulation) Model#y (sensors) Date - 4

5 SimEFM, a mix of numerical and hybrid Replacing the real OBC by its numerical model Real equipments are connected to the OBC model Real OBC (EM,, EQM,..) replaced by a commercial PC The real Flight Software controls real equipments FSW runs in the simulated OBC s are operated as identical to EFM/PFM configuration (using the same TM/TC sequences) Date - 5

6 SimEFM part of simulator product line Based on Astrium simulation infrastructure (SimTG) Shared across all simulations use cases No specific model development required Models, including OBC model and processor emulator, are fully reused Built with components shared with other systems HW interfaces identical as for hybrid configurations (EFM/PFM benches) User interface can be the simulator native one (SIMOPS) or the AIT CCS Date - 6

7 SimEFM architecture overview Power Supply Power (28 V) SIMEFM SW FSW HW Local CCS (SIMOPS) OBC Model (SCOC3 model) 1553 BC (HW) 1553 bus Real #1 Synchro signal (if needed) models models models 1553 RT (HW) AIT CCS Dynamic I/O, analog,.. I/F Scheduling, communication,... External SCOE I/F External SCOE (stimulation, acquisition) Simulator infrastructure (SimTG) 128 Hz Synchro. Date - 7

8 SimEFM is a real time simulator Using real equipments brings a hard real-time constraint Generation of command signals to equipments SimEFM is configured differently compared to a classical numerical simulator Use of RedHawk Linux OS Simulation cycles real-time synchronised to a reference clock Avionics bus I/F (e.g. Mil 1553) directly connected to the PC internal bus OBC model Messages BC + date 1553 messages FIFO System (real) time, application date 1553 BC task BC messages Mil-1553 BC messages HW scheduler Mil-1553 HW card Date - 8

9 SimEFM manages different HW interfaces In addition to avionics bus I/F s external I/O (e.g. status acquisition, configuration strap ) External SCOE such as complex stimulators Synchronisation signals (e.g. PPS) With different technologies Implemented with PCI cards plugged on the PC Ethernet link or specific bus adapter to dedicated SCOEs Can be operated without models Directly controlled by user test sequences In early phases, check of electrical compatibility Later on, upgraded to its complete configuration for functional validation Date - 9

10 SimEFM prototype implemented Based on Astrium latest OBC emulator for LEON3 Use of elements from the Astrium AstroBus 250 program Two real equipments : CMG, FOG All the models directly reused from AstroBus 250 simulators Reference case from AIT EFM test campaign Already validated FSW, SRDB and test sequences SIMEFM Local CCS (simops) Simulator infrastructure (SimTG) SCOC3 Model with AS250 CSW 1553 BC (HW) 1553 bus FOG CMG AS250 CCS (Open Center) s AS250 s models s models model complement model complement 1553 RT (HW) Sync. (HW) Eth. PCI/VME FOG stimuli sync. (128 Hz) FOG stimul. CMG SCOE (VME) SW HW FOG power CMG power Power Supply & protections Date - 10

11 SimEFM prototype results The FSW controls equipments as if running in real OBC The SimEFM generates all 1553 messages in real time Fidelity, compared to real EFM measurements, is less than 3 µs Period of FOG 1553 messages on EFM Period of FOG 1553 messages on SIMEFM The prototype was able to run the same tests as EFM bench Starting with simple equipment management (AOCS function disabled) Ending with a complete AOCS closed-loop test Date - 11

12 SimEFM user experience Versatility in bench operation Reuse of tests sequences from AIT EFM bench Enriched with numerical simulators debug tools Prototype has demonstrated efficiency for test setup User can switch from full simulated configuration to HW in the loop Real CMG on the 1553 bus Simulated CMG (CMG model on SIMEFM) Date - 12

13 SimEFM use cases for platform AIV SimEFM used instead, or in parallel, of an EFM bench Cost efficient reduction of EFM bottleneck Optimization and flexibility of the AIV Process Activities can be parallelised on less complex configurations Replacing EFM bench on programs based on recurrent platform Instruments or new equipments can be tested on SimEFM and then, directly integrated on PFM Effort and planning reduction per test (efficiency for test setup) Decrease the number of real OBCs necessary to the project for all validation activities Date - 13

14 SimEFM for equipments or P/L development Electrical tests during development/qualification phases SimEFM is representative of OBC or platform electrical interfaces SimEFM can be easily deployed at supplier premises Pre-coupling tests, representative HW/SW and system validation tests SW validation with real FSW can be done directly at supplier level Pre-test on FSW-SRDB and equipments compatibility Early coupling activities between equipment and their external SCOE/EGSE Complex SCOEs can be integrated/validated on SimEFM in parallel of EFM bench GNSS receiver with GPS/GNSS constellation simulator STR with optical/electrical Stimulator Date - 14

15 Conclusion SimEFM offers opportunities for the improvement of the Functional Validation process SimEFM combines state of the art technologies from Astrium numerical simulators and EGSE It offers opportunities to reduce costs and schedule on future space programs Date - 15

16 Thanks for your attention Denis Chatelais, Wilfrid Gonzalez ACE83 ASTRIUM Satellites 31 rue des Cosmonautes Z.I. du Palays F Toulouse Cedex 4 denis.chatelais@astrium.eads.net wilfrid.gonzalez@astrium.eads.net Date - 16