TPT-AstroBus

A complete, modular, Rust-native flight software (FSW) bus for small satellites (LEO / smallsats). It is the entire operating environment for a satellite — not a single component — providing the Application Framework, Executive Services, a zero-copy message bus, an FDIR engine, CCSDS/CFDP space protocols, and ADCS/EPS/Thermal/Comms subsystem drivers, all with guaranteed memory safety.

Built #![no_std], with a strictly static, compile-time-bounded memory strategy. No heap, no alloc, no fragmentation, no out-of-memory panics in orbit.

Why

Small-sat flight software is dominated by NASA's legacy C-based Core Flight System (cFS) and fragmented proprietary C++ codebases — systems that suffer from memory corruption, pointer errors, and painful concurrent task management. TPT-AstroBus replaces shared-memory pointers with strictly-typed, zero-copy, lock-free message queues, eliminating whole classes of race conditions and memory bugs at compile time.

Architecture

┌──────────────────────────────────────────────────────────────┐
│                      Application Framework                    │
│   ADCS │ EPS │ Thermal │ Comms │ (mission apps)              │
├──────────────────────────────────────────────────────────────┤
│                      Executive Services                       │
│   astrobus-sched (custom preemption)  │  astrobus-embassy     │
├───────────────────────────┬──────────┴───────────────────────┤
│      Message Bus          │           FDIR Engine            │
│   (astrobus-core)         │        (astrobus-fdir)           │
├───────────────────────────┴──────────────────────────────────┤
│   astrobus-ccsds │ astrobus-cfdp │ astrobus-tlm │ astrobus-hal│
├──────────────────────────────────────────────────────────────┤
│              astrobus-alloc  (static arena + pools)           │
└──────────────────────────────────────────────────────────────┘

Subsystems communicate only through the message bus — never through shared mutable state.

See ARCHITECTURE.md for the full layered design, data-flow diagrams (uplink / downlink / FDIR), and the scheduler-backend model.

Crates

Crate	Purpose	Status
astrobus-alloc	Const-generic static arena allocator, object pools, fixed-capacity collections	✅ v0.1
astrobus-core	Message envelope, zero-copy queues, message bus, executive-services trait	✅ v0.1
astrobus-sched	Custom Rust-native priority scheduler + Embassy adapter (feature-flagged backends)	✅ v0.1
astrobus-fdir	Fault Detection, Isolation, Recovery engine	✅ v0.1
astrobus-ccsds	CCSDS Space Packet Protocol	✅ v0.1
astrobus-cfdp	CCSDS File Delivery Protocol (fully compliant)	✅ v0.1
astrobus-tlm	Telemetry / telecommand serialization	✅ v0.1
astrobus-hal	Hardware abstraction (embedded-hal extensions, QEMU targets)	✅ v0.1
astrobus-adcs / astrobus-eps / astrobus-thermal / astrobus-comms	Subsystem driver traits + simulated reference impls	✅ v0.1
astrobus (meta)	Re-exports the sub-crates behind feature flags + example image	✅ v0.1

Memory strategy

Space-grade processors are slow and lack MMUs, making dynamic allocation dangerous. TPT-AstroBus allocates everything at compile time using Rust const generics and arena allocators. Capacity is a const parameter, so the linker reserves exactly the memory you need and the compiler rejects anything that would overflow it. Exhaustion is handled by Option/Result, never by a panic.

Getting started

cargo build --workspace
cargo test  --workspace

See each crate's README.md for details. The recommended first publish is astrobus-alloc + astrobus-core (this 0.1.0), with protocols and drivers landing in later minor versions.

Release process, MSRV policy, semver policy, and the dependency-ordered publish list are documented in RELEASING.md.

License

Licensed under either of

• Apache License, Version 2.0 (LICENSE-APACHE)
• MIT license (LICENSE-MIT)

at your option.

Contribution

Unless you explicitly state otherwise, any contribution intentionally submitted for inclusion in the work by you, as defined in the Apache-2.0 license, shall be dual licensed as above, without any additional terms or conditions.