(ST)Ruckig

Instantaneous Motion Generation for Robots and Machines.
Port of ruckig to Structured Text, TwinCAT 3.

This repository ports pantor/ruckig to Structured Text to bring open-source powered Online-Trajectory-Generation to TwinCAT 3. Only the Community Version of Ruckig is ported and pro features are not available. Struckig itself is dual licenced, you can use the source code provided here accordingly to GPLv3. If you want to use this commercially and not disclose your own source code, Struckig is also available with a custom licence. In the latter case, contact me.

Porting progress

The original project, ruckig is a submodule of this repository. The commit-hash reflects the commits that are ported already - I try to keep up with changes that are done in ruckig.

Unittests

This project uses TcUnit for unittesting. Since the library is a standalone PLC project, unittests are implemented in a different solution (subfolder .test/Struckig/Struckig_unittest) than the library. In order to execute the unittests the Struckig library has to be saved and installed and TcUnit.library has to be downloaded and installed.

Please note, that not all unittests from the original source code are ported yet, but only the KnownExamples and SecondaryFeatures tests.

Continuous integration

Continuous integration has not really arrived in Operational technology (OT) -- yet. Some fellows from work are making good progress in implementing buildtools and preparing a CI/CD environment for TwinCAT that will be publicly available. Luckily, they agreed with me to let me try their tools as an alpha/beta tester with this project. For more information on this topic, please contact Zeugwerk; In the meantime I thank @Zeugwerk for letting me use their build environment in this early development stage of their DevOps tools.

Documentation

The source code and usage documentation of this library is hosted on https://stefanbesler.github.io/Struckig/. Kudos again to @Zeugwerk for letting me beta test their TwinCAT documentation generation, which is still in alpha phase.

Example: Create time-based profile for 1 axis

This examples shows how to create a single-axis trajectory from point A=0mm to point B=100mm. The initial state assumes that the trajectory is in stillstand and target velocity and acceleration is set to 0. The MinDuration parameter is set to 10s. Please not that MaxVelocity, MaxAcceleration and MaxJerk would allow for a shorter travel time, but if MinDuration together with Synchronization = SynchronizationType.TimeSync is set, the MinDuration parameter is considered instead.

PROGRAM Example
VAR
  otg : Struckig.Otg(cycletime:=0.001, dofs:=1) := (
    EnableAutoPropagate := TRUE, //< Automatically copies the new trajectory state to the current trajectory state with every otg() call
    Synchronization :=     SynchronizationType.TimeSync, //< Set to TimeSync, otherwise MinDuration is ignored
    MinDuration :=         10.0, //< if MinDuration > 0 and Synchronization is set to TimeSync this sets the duration of the trajectory (if the other limitations would yields a shorter duration)
    MaxVelocity :=         [ 2000.0 ],
    MaxAcceleration :=     [ 20000.0 ],
    MaxJerk :=             [ 800000.0 ],
    CurrentPosition :=     [ 0.0 ],
    CurrentVelocity :=     [ 0.0 ],
    CurrentAcceleration := [ 0.0 ],
    TargetPosition :=      [ 100.0 ],
    TargetVelocity :=      [ 0.0 ],
    TargetAcceleration :=  [ 0.0 ]
  );
END_VAR

// =====================================================================================================================

otg();
// axis.SetTargetPosition(otg.NewPosition[0]); send the new position to your axis, which should be in a cyclic position mode
// axis.SetVelocityOffset(otg.NewVelocity[0]); send the new velocity to your axis, e.g. with a velocity feedforward
// axis.SetTorqueOffset( accelerationTorqueFactor * otg.NewAcceleration[0]) send the new acceleration to your acces, e.g. with a current feedforward