Ruckig

0.17.3 verified Fri May 01 auth: no python

Ruckig is a real-time motion generation library for robots and machines, providing instantaneous trajectory generation for up to 7 degrees of freedom. Current version 0.17.3, requires Python >=3.9. Released under the MIT license, with active development on GitHub.

pip install ruckig

Common errors

error ImportError: cannot import name 'Ruckig' from 'ruckig' ↓

cause Trying to import Ruckig directly with `import Ruckig` instead of `from ruckig import Ruckig`.

fix

Use from ruckig import Ruckig.

error TypeError: __init__() missing 1 required positional argument: 'dofs' ↓

cause Creating a Ruckig instance without specifying the number of degrees of freedom.

fix

Pass DOF as an integer: Ruckig(1) for single-degree-of-freedom.

error ValueError: The input parameter vector size does not match the DOFs. ↓

cause Setting a field (e.g., `current_position`) with a list of wrong length or a scalar.

fix

Ensure all field lists have length equal to DOF. For 1 DOF, use [value].

Warnings

breaking In version 0.17.0, the method `calculate` now returns a `Result` enum instead of a boolean. Code checking for `True`/`False` will break. ↓

fix Check for `Result.Working` or `Result.Finished` (see docs). For a quick fix, use `bool(result == Result.Working)` if you need a boolean.

deprecated The `Ruckig.set_max_*` methods are deprecated as of 0.17.0. Set limits directly via `InputParameter.max_velocity`, etc. ↓

fix Replace `otg.set_max_velocity(1.0)` with `inp.max_velocity = [1.0]`.

gotcha All position, velocity, acceleration, and limit fields must be lists of floats (even for 1 DOF). Passing a scalar will raise an error. ↓

fix Wrap scalars in a list: `inp.current_position = [0.0]`.

gotcha The first call to `calculate` often returns `Result.Working` even if the trajectory is trivial. You must call `calculate` repeatedly until it returns `Result.Finished`. ↓

fix Use a loop: while (result := otg.calculate(inp, out)) == Result.Working: pass, or use an iterator.

breaking Python 3.8 support dropped in version 0.16.0. ↓

fix Upgrade to Python >=3.9.

Imports

Ruckig
wrong
```
import Ruckig
```
correct
```
from ruckig import Ruckig
```
Common mistake: Ruckig is a class inside the module, not a top-level import.
InputParameter
```
from ruckig import InputParameter
```
OutputParameter
```
from ruckig import OutputParameter
```
Result
```
from ruckig import Result
```

Quickstart

Basic example of generating a 1-DOF trajectory from current state to target.

from ruckig import Ruckig, InputParameter, OutputParameter, Result

# Create Ruckig instance (DOF=1)
otg = Ruckig(1)

# Set input parameters
inp = InputParameter(1)
inp.current_position = [0.0]
inp.current_velocity = [0.0]
inp.current_acceleration = [0.0]
inp.target_position = [1.0]
inp.target_velocity = [0.0]
inp.target_acceleration = [0.0]
inp.max_velocity = [1.0]
inp.max_acceleration = [1.0]
inp.max_jerk = [10.0]

out = OutputParameter(1)

result = otg.calculate(inp, out)
if result == Result.Working:
    print('Trajectory generated: {} steps'.format(out.trajectory.duration))
elif result == Result.Finished:
    print('Already at target.')
else:
    print('Invalid input.')