Crate stepgen

Stepper motor speed ramp generator.

Given acceleration, target speed and target step to stop at, generates acceleration or deceleration profile for the stepper motor, in the form of delays between steps.

Uses algorithm from "Generate stepper-motor speed pro les in real time" paper by David Austin.

Examples

use stepgen::Stepgen;

let mut stepper = Stepgen::new(1_000_000);

stepper.set_acceleration(1000 << 8).unwrap(); // 1200 steps per second per second
stepper.set_target_step(1000); // stop at step 1000
stepper.set_target_speed(800 << 8).unwrap(); // 240RPM (4 turns per second)

// Take 99 steps
for _ in 0..99 {
    stepper.next();
}

assert_eq!(99, stepper.current_step());
assert_eq!(113621, stepper.current_speed());
assert_eq!(2242, (stepper.next() + 128) >> 8); // delay for 100th step, rounded to nearest integer

Note on numbers

In few APIs, stepgen keeps numbers as fixed-point numbers, using least significant 8 bits for the fractional part and the remaining bits for the integral part.

Links

Structs

Stepgen

State of the stepgen.

Enums

Error

Error code for some of the stepgen operations.

Type Definitions

Result

Result type for some of the stepgen operations.