Crate accel_stepper

A Rust port of the popular AccelStepper Arduino stepper library.

Basic Usage

The most common way of using this crate is by driving an axis to a particular location.

use accel_stepper::{Driver, SystemClock};
 
let mut axis = Driver::new();
// Make sure to set your device's motion parameters
axis.set_max_speed(500.0);
axis.set_acceleration(100.0);
 
// The axis needs a clock for timing purposes. This could be an
// `accel_stepper::OperatingSystemClock` when compiled with the `std`
// feature, or your device's external oscillator
 
#[derive(Debug, Default)]
struct TickingClock(RefCell<Duration>);
 
impl SystemClock for TickingClock {
    fn elapsed(&self) -> Duration {
        let mut ticks = self.0.borrow_mut();
        *ticks = *ticks + Duration::from_millis(10);
        ticks.clone()
    }
}
 
let clock = TickingClock::default();
 
let mut forward = 0;
let mut back = 0;
 
{
    // for testing purposes, we'll create a Device which counts the number
    // of forward/backward steps
    let mut dev = accel_stepper::func_device(|| forward += 1, || back += 1);
 
    // set the desired location
    axis.move_to(17);
 
    // keep polling the axis until it reaches that location
    while axis.is_running() {
        axis.poll(&mut dev, &clock)?;
    }
}
 
// we should have arrived at our destination
assert_eq!(17, axis.current_position());
 
// it takes 17 steps forward to reach position 17
assert_eq!(17, forward);
assert_eq!(0, back);

Cargo Features

To minimise compile time and code size, this crate uses cargo features.

• std - Enable functionality which depends on the standard library (e.g. the OS clock)
• hal - Enable functionality which implements Device on top of traits from the embedded-hal crate.

Structs

CummulativeSteps

A helper type for determining the number of steps to take when moving a distance in the real world, taking rounding errors into consideration.

Driver

A stepper motor driver.

MultiDriver

Controller for moving multiple axes in a coordinated fashion.

OperatingSystemClock

A monotonically non-decreasing clock backed by the operating system.

StepAndDirection

A Device which has step and direction pins.

StepContext

Extra contextual information passed to a Device when its Device::step() method is invoked.

Traits

Device

An interface to the stepper motor.

SystemClock

Something which records the elapsed real time.

Functions

fallible_func_device

A device which uses callbacks which may fail.

func_device

A Device which will call one function for a forward step, and another for a backward one.