Crate pidgeon 

High-performance PID controller with no_std support, IIR-filtered derivative, configurable anti-windup, and optional thread safety.

Architecture

The library is split into two layers:

• Pure function: pid_compute takes a ControllerConfig and PidState, returns a control output and updated state. Works in no_std environments.
• Stateful controllers (requires std): PidController and ThreadSafePidController wrap the pure function with automatic state management and performance statistics.

Quick start

use pidgeon::{ControllerConfig, PidState, pid_compute};

// 1. Build a validated config
let config = ControllerConfig::builder()
    .with_kp(2.0)
    .with_ki(0.5)
    .with_kd(0.1)
    .with_setpoint(100.0)
    .with_output_limits(0.0, 255.0)
    .build()
    .unwrap();

// 2. Start with default state
let mut state = PidState::default();

// 3. Run the control loop
let dt = 0.01; // 10 ms
for _ in 0..100 {
    let process_value = 80.0; // read from sensor
    let (output, next_state) = pid_compute(&config, &state, process_value, dt).unwrap();
    state = next_state;
    // apply `output` to actuator
}

Feature flags

Feature	Default	Effect
std	yes	Enables PidController, ThreadSafePidController, and Error impl
debugging	no	Streams PID telemetry via Iggy.rs (implies std)
benchmarks	no	Enables criterion benchmarks (implies std)
wasm	no	Swaps std::time for web_time (implies std)

Structs

ControllerConfig

Validated, immutable PID controller configuration.

ControllerConfigBuilder

Builder for ControllerConfig. Collects PID parameters without validation until build() is called.

ControllerStatistics

Runtime performance metrics for a PidController.

PidController

Stateful PID controller with built-in performance statistics.

PidState

Persistent state carried between pid_compute invocations.

ThreadSafePidController

Thread-safe PID controller backed by Arc<Mutex<PidController>>.

Enums

AntiWindupMode

Anti-windup strategy for the integral term.

DerivativeMode

Selects which signal the derivative term operates on.

PidError

Error type for PID controller operations.

Functions

pid_compute

Computes one PID control step as a pure function.