Example 07: Minimum Trajectory Duration

C++

#include <iostream>
 
#include <ruckig/ruckig.hpp>
 
 
using namespace ruckig;
 
int main() {
    // Create instances: the Ruckig OTG as well as input and output parameters
    Ruckig<3> otg {0.01};  // control cycle
    InputParameter<3> input;
    OutputParameter<3> output;
 
    // Set input parameters
    input.current_position = {0.0, 0.0, 0.5};
    input.current_velocity = {0.0, -2.2, -0.5};
    input.current_acceleration = {0.0, 2.5, -0.5};
 
    input.target_position = {-5.0, -2.0, -3.5};
    input.target_velocity = {0.0, -0.5, -2.0};
    input.target_acceleration = {0.0, 0.0, 0.5};
 
    input.max_velocity = {3.0, 1.0, 3.0};
    input.max_acceleration = {3.0, 2.0, 1.0};
    input.max_jerk = {4.0, 3.0, 2.0};
 
    // Set minimum duration (equals the trajectory duration when target velocity and acceleration are zero)
    input.minimum_duration = 5.0;
 
    // Generate the trajectory within the control loop
    std::cout << "t | p1 | p2 | p3" << std::endl;
    while (otg.update(input, output) == Result::Working) {
        auto& p = output.new_position;
        std::cout << output.time << " " << p[0] << " " << p[1] << " " << p[2] << " " << std::endl;
 
        output.pass_to_input(input);
    }
 
    std::cout << "Trajectory duration: " << output.trajectory.get_duration() << " [s]." << std::endl;
}

Python

from copy import copy
from pathlib import Path
from sys import path
 
# Path to the build directory including a file similar to 'ruckig.cpython-37m-x86_64-linux-gnu'.
build_path = Path(__file__).parent.absolute().parent / 'build'
path.insert(0, str(build_path))
 
from ruckig import InputParameter, OutputParameter, Result, Ruckig
 
 
if __name__ == '__main__':
    otg = Ruckig(3, 0.01)
    inp = InputParameter(3)
    out = OutputParameter(3)
 
    # Set input parameters
    inp.current_position = [0.0, 0.0, 0.5]
    inp.current_velocity = [0.0, -2.2, -0.5]
    inp.current_acceleration = [0.0, 2.5, -0.5]
 
    inp.target_position = [-5.0, -2.0, -3.5]
    inp.target_velocity = [0.0, -0.5, -2.0]
    inp.target_acceleration = [0.0, 0.0, 0.5]
 
    inp.max_velocity = [3.0, 1.0, 3.0]
    inp.max_acceleration = [3.0, 2.0, 1.0]
    inp.max_jerk = [4.0, 3.0, 2.0]
 
    # Set minimum duration (equals the trajectory duration when target velocity and acceleration are zero)
    inp.minimum_duration = 5.0;
 
 
    print('\t'.join(['t'] + [str(i) for i in range(otg.degrees_of_freedom)]))
 
    # Generate the trajectory within the control loop
    first_output, out_list = None, []
    res = Result.Working
    while res == Result.Working:
        res = otg.update(inp, out)
 
        print('\t'.join([f'{out.time:0.3f}'] + [f'{p:0.3f}' for p in out.new_position]))
        out_list.append(copy(out))
 
        out.pass_to_input(inp)
 
        if not first_output:
            first_output = copy(out)
 
    print(f'Calculation duration: {first_output.calculation_duration:0.1f} [µs]')
    print(f'Trajectory duration: {first_output.trajectory.duration:0.4f} [s]')
 
    # Plot the trajectory
    # path.insert(0, str(Path(__file__).parent.absolute().parent / 'test'))
    # from plotter import Plotter
 
    # Plotter.plot_trajectory(Path(__file__).parent.absolute() / '7_trajectory.pdf', otg, inp, out_list, plot_jerk=False)

Output Trajectory