@dc42 said in S-Curve/ sinusoidal , Jerk +acceleration:
Unfortunately, in 3D printing we have a much worse problem, which is that curves are approximated by straight lines. This unfortunately forces us into making the first derivative of position discontinuous, to avoid dropping the speed to zero at every boundary between line segments in a curve. As long as we are forced to do this, there is very little point in worrying about the discontinuity of the second derivative.
If we ever reach the situation where the model files we slice represent curves properly, and the slicers that generate gcode from them generate Bezier curves, cubic splines or some other representation of curves, then implementing smooth changes in acceleration may be worth looking into.
Yes, but that would also mean whole new generation of modelling tools, gcode, slicers - generally the whole toolset. Can't we have a feature which approximates segmented movement using curves? Supporting curves way down the pipeline in the firmware is a thing that can be reused once the slicers are up to par.
The thing about curves is that nothing is a 100% curve. The 3d models are meshes or a mix of corners and curves that would otherwise need to be approximated somewhere, be it in firmware (if hardware permits) or PC application software as a pre-processing step.