Struct Odometry 

pub struct Odometry { /* private fields */ }

Tracks a robot’s Pose by accumulating its motion over time (odometry).

With no GPS indoors, a robot estimates where it is by adding up where it has been: each small move is integrated onto the running pose. This uses the exact arc model rather than a straight- line step, so a robot that drives and turns at once follows the curve it actually traces instead of cutting the corner; over many steps that is markedly more accurate. Feed it either a body motion (forward speed and yaw rate over a time step) or wheel-distance deltas through a DiffDrive model. Dead reckoning drifts, so correct the heading from an absolute source with fuse_heading when one is available.

Examples

use pamoja_kit::{Odometry, Pose};

// Drive a quarter circle of radius 1 m: forward 1 m/s, turning left at 1 rad/s, for pi/2 s.
let mut odom = Odometry::at_origin();
let pose = odom.integrate(1.0, 1.0, core::f32::consts::FRAC_PI_2);

// It ends about (1, 1) facing 90 degrees, the far corner of the arc.
assert!((pose.x - 1.0).abs() < 1e-5);
assert!((pose.y - 1.0).abs() < 1e-5);
assert!((pose.theta - core::f32::consts::FRAC_PI_2).abs() < 1e-5);

Implementations

impl Odometry

pub fn new(start: Pose) -> Self

Creates an estimator starting from a known pose.

Arguments

• start - the initial pose.

Returns

The estimator.

pub fn at_origin() -> Self

Creates an estimator starting at the origin facing along the x axis.

Returns

The estimator.

pub fn pose(&self) -> Pose

Returns the current pose estimate.

Returns

The pose accumulated so far.

pub fn reset(&mut self, pose: Pose)

Resets the estimate to a known pose.

Arguments

• pose - the pose to set.

pub fn integrate(&mut self, linear: f32, angular: f32, dt: f32) -> Pose

Integrates a body motion over a time step and returns the new pose.

Arguments

• linear - the forward speed.
• angular - the yaw rate, positive turning left.
• dt - the length of the time step.

Returns

The updated pose.

pub fn integrate_wheels( &mut self, left: f32, right: f32, drive: &DiffDrive, ) -> Pose

Integrates wheel-distance deltas through a differential-drive model.

Arguments

• left - the distance the left wheel rolled since the last update.
• right - the distance the right wheel rolled since the last update.
• drive - the DiffDrive model giving the track between the wheels.

Returns

The updated pose. The wheel deltas are turned into a forward distance and a heading change by DiffDrive::body_motion, then integrated as one arc.

pub fn fuse_heading(&mut self, measured: f32, weight: f32)

Corrects the heading toward an absolute measurement, the way a compass tames gyro drift.

This is the angular cousin of Complementary: it nudges the estimated heading along the shortest arc toward an absolute reading (an IMU yaw, a magnetometer, a GPS course) by a blend weight, leaving the position untouched.

Arguments

• measured - the absolute heading in radians.
• weight - how strongly to trust the measurement, clamped to [0, 1]; zero keeps the dead-reckoned heading, one snaps to measured.

Trait Implementations

impl Clone for Odometry

fn clone(&self) -> Odometry

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Copy for Odometry

impl Debug for Odometry

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.