This project presents the system-level design of a space mission inspired by the SOHO (Solar and Heliospheric Observatory) mission.
The objective is to perform a complete spacecraft design covering mission analysis, trajectory design, and all major subsystems, including propulsion, AOCS, communications, thermal control, power, and onboard data handling.
The mission focuses on continuous observation of the Sun and analysis of solar phenomena, including:
- Solar interior dynamics
- Coronal structure and heating
- Solar wind generation and propagation
The spacecraft operates in a halo orbit around the Sun–Earth L1 point, enabling:
- Continuous Sun observation
- Permanent communication with Earth
- Stable thermal and illumination conditions
- Launch and Early Orbit Phase (LEOP)
- Transfer Trajectory Phase
- Halo Orbit Phase with periodic station-keeping
The transfer trajectory from Earth to L1 includes:
- Injection from parking orbit
- Mid-course corrections
- Halo orbit insertion maneuver
A ΔV budget is derived considering:
- Transfer maneuvers
- Station keeping
- Attitude control contributions
- Monopropellant hydrazine system
- Pressure-fed (blowdown architecture)
- Helium pressurization
- 16 thrusters (4.5 N class)
Key aspects:
- ΔV-driven sizing using Tsiolkovsky equation
- Tank and pressurizer sizing
- Blowdown ratio selection
- Comparison with real mission data
- Three-axis stabilized spacecraft
- Reaction wheels for fine pointing
- Thrusters for momentum dumping and maneuvers
Control modes include:
- Nominal Sun-pointing mode
- Safe mode (Sun acquisition)
- Maneuver modes
- High Gain Antenna for nominal operations
- Low Gain Antennas for safe mode
- S-band communication
- Link budget and SNR analysis
- Passive and active thermal control strategies
- Single-node and multi-node thermal modeling
- Hot and cold case analysis
- Solar arrays sized for mission requirements
- Battery system for eclipse and peak loads
- Power budget evaluation
- Architecture design for data flow and storage
- Throughput and memory sizing
- Subsystem interfacing
The project demonstrates a consistent and feasible spacecraft design, including:
- Complete subsystem sizing
- Mission feasibility verification
- Consistent mass, power, and data budgets
- Comparison with real SOHO mission data
- Space mission design
- Halo orbits (L1)
- System engineering
- Propulsion sizing
- AOCS design
- Spacecraft subsystems integration
Matteo Portantiolo
MSc Space Engineering – GNC