#motion #trajectory #trajectories

cartesian_trajectories

create cartesian motion profiles

1 unstable release

0.1.0 May 6, 2021

#175 in Robotics

EUPL-1.2

41KB
659 lines

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cartesian_trajectories

cartesian_trajectories allows creating arbitrary cartesian trajectories and adding a velocity profile on top of it.

Example

use cartesian_trajectories::generate_absolute_motion;
use cartesian_trajectories::s_curve::SCurveConstraints;
use cartesian_trajectories::CartesianTrajectory;
use cartesian_trajectories::VelocityProfile::SCurve;
use nalgebra::Isometry3;
use std::time::Duration;

fn main() {
    let start_pose = Isometry3::translation(2., 2., 0.);
    let pose_generator = generate_absolute_motion(Isometry3::translation(1., 1., 0.));
    let mut trajectory = CartesianTrajectory::new(
        pose_generator,
        SCurve {
            start_pose,
            constraints: SCurveConstraints {
                max_jerk: 5.,
                max_acceleration: 5.,
                max_velocity: 5.,
            },
        },
    );
    for &i in [0., 0.5, 1.0].iter() {
        let time = trajectory.get_total_duration().mul_f64(i);
        let output = trajectory.get_pose(&start_pose, time);
        println!("{:?}", output);
        assert!(f64::abs(output.pose.translation.x + i - 2.) < 1e-7);
        assert!(f64::abs(output.pose.translation.y + i - 2.) < 1e-7);
        if i < 1. {
            assert!(!output.finished);
        } else {
            assert!(output.finished);
        }
    }
}

This example will generate a trajectory that moves from (2,2,0) to (1,1,0) with an SCurve motion. The trajectory can then be queried with trajectory.get_pose(), which takes the start pose and the current time. The start pose is needed as the trajectory is not precalculated.

Features

Predefined PoseGenerators for:

  • Relative motions
  • Absolute motions
  • Circle motions

Further, it is possible to define custom position and orientation generators and combine them to a pose generator. PoseGenerators can be combined by multiplication, for example, to create a spiral movement from a circle and a relative motion. It is also possible to concatenate multiple PoseGenerators.

A cartesian trajectory can then be created either by applying a custom velocity profile or using one of the following predefined velocity profiles:

  • Linear
  • Cosine
  • SCurve

Licence

This library is copyrighted © 2021 Marco Boneberger

Licensed under the EUPL, Version 1.2 or – as soon they will be approved by the European Commission - subsequent versions of the EUPL (the "Licence");

You may not use this work except in compliance with the Licence. You may obtain a copy of the Licence at:

https://joinup.ec.europa.eu/software/page/eupl

Unless required by applicable law or agreed to in writing, software distributed under the Licence is distributed on an "AS IS" basis WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.

See the Licence for the specific language governing permissions and limitations under the Licence.

Dependencies

~3.5MB
~69K SLoC