use-control

Composable primitive control-system utilities for Rust.

use-control is part of RustUse, alongside sibling repositories such as use-math, use-stats, use-optimization, use-simulation, use-color, use-text, use-time, and use-units. It groups small, focused crates for feedback loops, PID controllers, setpoints, error calculations, control signals, system response helpers, and simple stability-oriented utilities.

The RustUse approach in this workspace stays intentionally narrow:

• crates stay small and independently useful
• APIs stay explicit, documented, tested, and composable
• implementations favor practical f64 and usize helpers over framework-style abstractions
• dependencies stay minimal so each crate is easy to audit and adopt

Workspace crates

• use-control: thin facade crate that reexports the full control workspace
• use-feedback: primitive positive and negative feedback helpers
• use-pid: minimal PID gains, state, and controller updates
• use-setpoint: setpoint and tolerance checks
• use-control-error: control error, relative error, percent error, and deadband helpers
• use-control-signal: control signal validation, clamping, and saturation helpers
• use-system-response: first-order response functions and sampling helpers
• use-stability: gain classification, boundedness, and settling-time helpers

Facade crate

If you want one dependency for the whole workspace, use use-control. It reexports each focused crate and exposes the focused APIs directly so this works:

use use_control::*;

let mut controller = PidController::new(PidGains {
    kp: 2.0,
    ki: 0.5,
    kd: 0.0,
})
.unwrap();
let output = controller.update(10.0, 8.0, 0.5).unwrap();
let signal = ControlSignal::new(output).unwrap().clamp(0.0, 10.0).unwrap();

assert!(signal.value() >= 0.0);
assert!(within_tolerance(10.0, 9.9, 0.2).unwrap());

Status

This workspace is experimental while it remains below 0.3.0. Expect the public API to stay small and practical, but still evolve as the RustUse control surface becomes clearer.

Development

Run the standard workspace checks from the repository root:

cargo fmt --all -- --check
cargo clippy --workspace --all-targets -- -D warnings
cargo test --workspace
cargo doc --workspace --no-deps