Guidance, Navigation, and Control (GNC) Platform
Complete, Scalable Guidance, Navigation & Control System for CubeSats and MicroSats.
Space Inventor’s GNC platform is a fully integrated, flight-proven system combining all sensors, actuators, and control software required for precise spacecraft attitude and orbit control. Built exclusively from Space Inventor hardware and software, this modular suite offers a complete in-house solution that can be tailored to meet diverse mission requirements — from agile CubeSats to high-precision MicroSats operating in LEO, MEO, or GEO.
At its core, the GNC Solution uses the AOCS Computer (OBC-P4) running advanced Space Inventor algorithms for sensor fusion, guidance, and closed-loop control, ensuring robust performance and high reliability in orbit.
The number, type, and configuration of sensors and actuators are fully customizable and selected according to each mission’s specific requirements and objectives.
Core Functionality
Attitude Determination
Fused data from star trackers, IMU, magnetometers, and FSS modules using advanced Extended Kalman Filtering
Attitude Control Modes
The systems provides precision control using reaction wheels for fine maneuvers and magnetorquers for momentum management as well as several advanced control modes: Nadir, Velocity, ECI, Safe sun pointing, Sun pointing with tertiary pointing target, bore axis pointing with tertiary axis sun optimized, inertial pointing, limb tracking, target tracking, ground station tracking, push broom imaging mode
Orbit Determination
GNSS-based position and velocity tracking with integrated guidance algorithms
Momentum Management
Automatic unloading of wheel momentum using magnetorquer rods or propulsion system
Fault Tolerance
Hierarchical State Machine and FDIR framework provide autonomous fault detection and recovery
Typical Pointing Performance
Platform Type | Sensor and Actuator Suite | Typical Pointing Accuracy |
6U CubeSat | WHL-P4 + FSS + IMU-P4 | < 2º |
16U CubeSat | STR + WHL-P4 + FSS + IMU-P4 | 0.1º - 0.5º |
Microsat 50-200 kg (Micro-8 / Micro-24) | Dual STR + WHL-P4 + FSS + IMU-P4 | 50 arcsec |
Precision Missions (e.g. telescopes) | Dual STR + WHL-P4 + advanced calibration | Arcsecond (with in-orbit tuning) |
GNC Platform Subcomponents
AOCS Computer
The AOCS Computer and software (OBC-P4 + AOCS SW) is the central control unit of the GNC platform. It interfaces with all sensors and actuators via a redundant CAN bus using the CubeSat Space Protocol (CSP), managing real-time attitude and orbit control tasks.
Key features include:
Executes all AOCS and GNC software, including sensor fusion, actuator control, conops and FDIR
Robust, radiation-tolerant design with independent power and data interfaces
Quad-core ARM Cortex-M7 architecture for real-time parallel processing
The OBC-P4 ensures coordinated and deterministic operation of all subsystems, serving as the backbone of the GNC suite.
Actuators
GNC actuators Provide precise and stable attitude control and momentum management across all spacecraft axes.
The platform typically includes:
Reaction Wheels (WHL-P4 series): Fine 3-axis control and agile slews
Magnetorquer Rods (MT series): Momentum dumping and safe-mode stabilization
Optional Propulsion Interface: Various 3rd party propulsion systems can be added for orbit control and advanced maneuvering
The number and configuration of actuators are tailored to meet specific mission performance and redundancy requirements.
Sensors
A number of GNC sensors provide accurate and reliable attitude and orbit determination across multiple operating modes.
Typical sensor modules include:
Star Trackers (ASTRO-CL / SFC): High-precision attitude measurement with onboard image processing
Fine Sun Sensors (FSS): Coarse attitude and Sun-pointing capability
Inertial Measurement Unit (IMU-P4): Redundant gyroscopes, accelerometers, and magnetometers for continuous rate sensing
GNSS Receivers (GNSS-P3): Precise position and velocity data for orbit determination
Sensor configuration can be adapted for varying precision, redundancy, and environmental conditions.
Power & Communication Infrastructure
Power Distribution Units (PDU-P4) provide regulated and redundant power to all GNC components, with latch-up protection and integrated CAN communication across the subsystem network.
Performance & Heritage
The system achieves arcsecond attitude determination and high-precision control, verified across flight-proven Space Inventor missions in both LEO and GEO. Its modular, distributed architecture allows rapid adaptation to spacecraft mass, inertia, and mission profile — ensuring optimal GNC performance for satellites from 10 kg CubeSats up to 200+ kg MicroSats.
MSRP
