OpenSVF

Open-core spacecraft Software Validation Facility

OpenSVF is a Python-based platform for validating spacecraft flight software against a 6-DOF physics engine and a real PUS ground station. It is aimed at small satellite teams who write flight software in C and need a structured, traceable way to test it before hardware integration.

The core idea: your flight software binary runs inside the SVF. The SVF feeds it sensor data from a physics simulation, receives its actuator commands, closes the loop, and records everything. You write test procedures in Python that send telecommands and assert on telemetry. At the end you get an HTML campaign report with a requirement traceability matrix.

What it looks like

opensvf-kde (C++/Eigen3)        openobsw (C11)
  6-DOF rigid body dynamics        PUS S1/3/5/6/8/9/11/12/17/19/20
  Euler equations                  b-dot detumbling
  Magnetic field model             ADCS PD controller
        │                          FDIR + watchdog
        │  FMI 2.0 Co-Simulation         │
        ▼                                ▼
              OpenSVF (Python)
         ┌────────────────────────────┐
         │  Sensor models             │  magnetometer, gyroscope,
         │  (noise, bias, FDIR faults)│  star tracker, CSS, GPS, RW
         │                            │
         │  Bus adapters              │  MIL-STD-1553B, SpaceWire,
         │                            │  CAN 2.0B (ECSS)
         │                            │
         │  PUS TM/TC stack           │  ECSS-E-ST-70-41C
         │                            │
         │  Campaign runner           │  Procedure → verdict → HTML
         └────────────────────────────┘
                    │ PUS TM/TC
                    ▼
             YAMCS 5.12.6
          (ground station)

Compatibility

Prerequisites

• Linux (Ubuntu 22.04+), WSL2 (Ubuntu 24.04), or GitHub Codespaces
• Python 3.11+
• Eclipse Cyclone DDS (pip install cyclonedds)
• Java 21+ (for YAMCS ground station)
• Docker Desktop + VS Code Dev Containers extension (for local development)

The setup script handles the rest.

Quick start

git clone https://github.com/lipofefeyt/opensvf
cd opensvf
pip install -e ".[dev]"                                           # install SVF and dev dependencies

testosvf                                                          # 606 unit + integration tests
checkcov                                                          # requirement coverage report
svf profiles                                                      # list bundled hardware profiles
svf check mission_mysat1/spacecraft.yaml
svf campaign mission_mysat1/campaigns/quickstart_campaign.yaml --report

The campaign produces results/report.html - open it in a browser.

To start the YAMCS ground station:

bash scripts/start-yamcs.sh     # downloads YAMCS 5.12.6 if not present, starts on port 8090

Validation pyramid

OpenSVF is structured around a four-level validation pyramid:

CI runs L1 + L2 (no compiled flight software needed). L3 and L4 require the openobsw binary and opensvf-kde FMU.

Three modes of operation

1. Stub mode (unit testing, no binary)

# spacecraft.yaml
obsw:
  type: stub

The OBC is replaced by a rule-based stub. All sensors and actuators run. Use this for rapid iteration on test procedures before you have a flight binary.

2. Pipe mode (host simulation, CI)

obsw:
  type: pipe
  binary: ./bin/obsw_sim        # x86_64 or aarch64 via QEMU

The real flight software binary runs as a subprocess. SVF feeds it sensor frames over stdin/stdout using wire protocol v3. This is the primary SIL validation mode and runs in CI with no special hardware.

3. Socket mode (Renode ZynqMP emulation)

obsw:
  type: socket
  host: localhost
  port: 3456

The flight software runs inside Renode emulating a ZynqMP Cortex-A53. SVF connects to the Renode UART terminal over TCP. Same wire protocol - the flight binary never knows the difference.

Writing a test procedure

from svf.campaign.procedure import Procedure, ProcedureContext

class BdotConvergence(Procedure):
    id          = "TC-AOCS-001"
    title       = "B-dot detumbling convergence"
    requirement = "MIS-AOCS-042"

    def run(self, ctx: ProcedureContext) -> None:
        self.step("Power on sensors")
        ctx.inject("aocs.mag.power_enable", 1.0)
        ctx.inject("aocs.gyro.power_enable", 1.0)

        self.step("Monitor angular rate for 60s")
        monitor = ctx.monitor("aocs.gyro.rate_x", less_than=0.5)
        ctx.wait(60.0)
        monitor.assert_no_violations()

        self.step("Verify convergence")
        ctx.assert_parameter("aocs.gyro.status", greater_than=0.5)

# campaign.yaml
campaign: MySat-1 AOCS Validation
spacecraft: mission_mysat1/spacecraft.yaml
procedures:
  - procedures/test_bdot.py

svf campaign campaign.yaml --report

Fault injection

# Star tracker stuck fault for 10 seconds
ctx.inject_equipment_fault(
    "str1", "aocs.str1.quaternion_w",
    fault_type="stuck", value=0.0, duration_s=10.0
)

# Magnetometer bias
ctx.inject_equipment_fault(
    "mag1", "aocs.mag.field_x",
    fault_type="bias", value=1e-5, duration_s=30.0
)

Fault types: stuck | noise | bias | scale | fail

Temporal assertions

# "Angular rate shall never exceed 0.1 rad/s during detumbling"
monitor = ctx.monitor("aocs.truth.rate_magnitude", less_than=0.1)
ctx.wait(60.0)
monitor.assert_no_violations()

result = monitor.summary()
# result.compliant, result.violations, result.min_value, result.max_value

Hardware profiles

Ten bundled profiles cover common small satellite components:

svf profiles          # list all available

Bus adapters

YAMCS ground station

OpenSVF integrates with YAMCS 5.12.6 as an optional ground station. The XTCE mission database is generated automatically from the SRDB.

bash scripts/start-yamcs.sh     # start YAMCS on port 8090
python3 scripts/demo_yamcs.py   # run a demo TC/TM exchange
bash scripts/stop-yamcs.sh      # stop YAMCS

The YAMCS UI is available at http://localhost:8090 (default credentials: admin / password).

TC pipeline: YAMCS UI → UDP port 10025 → SVF → obsw_sim TM pipeline: obsw_sim → SVF → TCP port 10015 → YAMCS packet viewer

Developer tools

testosvf                              # full test suite (606 tests, L1+L2)
checkosvf                             # mypy strict type check
svf validate spacecraft.yaml          # fast pre-flight config check (no DDS, no FMU)
checkcov                              # requirement coverage + equipment fidelity report
checkcons                             # SRDB consistency: 7 checks including namespace lint
regen-xtce                            # regenerate YAMCS XTCE database from SRDB

Local development (WSL2 + Dev Containers)

# Windows (PowerShell admin)
wsl --install -d Ubuntu-24.04
winget install -e --id Docker.DockerDesktop --source winget
winget install -e --id dorssel.usbipd-win --source winget

# WSL2
git clone https://github.com/lipofefeyt/opensvf ~/workspace/opensvf
git clone https://github.com/lipofefeyt/openobsw ~/workspace/openobsw
git clone https://github.com/lipofefeyt/opensvf-kde ~/workspace/opensvf-kde
code ~/workspace/opensvf   # VS Code detects .devcontainer/ → Reopen in Container

The dev container mounts openobsw and opensvf-kde as sibling workspaces at /workspace/.

Repository layout

src/svf/
├── campaign/       CampaignRunner, Procedure, HTML reporter
├── models/
│   ├── aocs/       magnetometer, gyroscope, star_tracker, magnetorquer,
│   │               reaction_wheel, css, bdot_controller, thruster, gps
│   ├── dynamics/   KDE FMU wrapper (6-DOF physics, external C++ project)
│   ├── eps/        solar_array, battery, pcdu  (NativeEquipment factories)
│   ├── dhs/        OBCStub, OBCEmulatorAdapter (pipe + socket)
│   └── ttc/        TTC, S-band transponder
├── bus/            MIL-STD-1553B, SpaceWire, CAN
├── pus/            PUS-C TM/TC stack: tc, tm, services/ (S1/3/5/9/11/12/17/19/20)
├── stores/         ParameterStore, CommandStore
└── config/         SpacecraftLoader, HardwareProfile, SRDB

mission_mysat1/     Reference mission configuration
tools/              check_coverage.py, srdb_consistency_check.py, generate_xtce.py
yamcs/              YAMCS config, XTCE MDB, processor config
scripts/            start-yamcs.sh, stop-yamcs.sh, activate.sh

Related projects

Roadmap

License

Apache 2.0

Built by lipofefeyt