Re: Acceleration Settings
In addition, Craftware is truly wonderful in how it shows line by line moves, and scrolls the actual gcode visually for those moves. Feed rates are shown by color, and it is clear that deceleration and acceleration in a single line is shown with fading colors in the sliced object view. Simplify3D's preview is truly lacking in comparison...
Re: Acceleration Settings
The speed changes there aren't what I would consider real acceleration, and if you tried running that on a machine with no firmware acceleration control it'd still be all sorts of jerky. You want smooth transitions in speed, not sudden jerks. Craftware is still relying on the printer firmware handling the speed changes smoothly, it's just slowing down for corners a bit more. I'd be interested in a real test to see if this leads to any real print quality improvement as compared to the same acceleration settings just being in firmware. I doubt it.Caall99 wrote:dorsai3d,
Lets see if i caught you on a less grumpy day... This might interest you:
A snippet from accelerated code generated by Craftware 1.14:
[...]
There are also the following settings under acceleration:
Max Accel: 1000mm/s^2
Corner Coefficient: 4
Min Speed: 4mm/s
I'd suggest you read up on what acceleration and motion planning is actually happening behind the scenes. You want to be able to change the step rate smoothly, which would mean that, for a truly accelerated segment of gcode, you'd need several hundred to several thousand lines of gcode every time you approach or leave a corner.
Some basic study materials to get you started:
http://forums.reprap.org/read.php?1,244006,244574
http://www.reprap.org/wiki/Firmware/Linear_Acceleration
http://wiki.linuxcnc.org/cgi-bin/wiki.p ... e_Tp_Notes
https://en.wikipedia.org/wiki/Jerk_(phy ... on_control
http://www.atmel.com/Images/doc8017.pdf
Re: Acceleration Settings
I will slice with CraftWare's acceleration feature, pass it through GPX, test it on my Sailfish firmware printer with and without firmware acceleration enabled, and report back.
I can vary the time step, and may try a very small interval like 1ms or 0.1ms if the slicer accepts it. I know its more code to parse, but its also less calculations for the microcontroller to perform. I'll read what you linked, thanks for sharing.
I can vary the time step, and may try a very small interval like 1ms or 0.1ms if the slicer accepts it. I know its more code to parse, but its also less calculations for the microcontroller to perform. I'll read what you linked, thanks for sharing.
Re: Acceleration Settings
It's not less calculations for the microcontroller to perform! What do you think it's doing when reading code? It still has to parse the instructions (everything a processor does is math!), add the requisite steps to the motion planner (this takes about the same amount of time regardless of acceleration planning) and then generate the step pulse (ramping up this pulse frequency doesn't add that much overhead compared to just starting pulses).
Which do you think takes more processing time on a microcontroller?
A) Receiving, storing, retrieving, and processing 500 lines of gcode, then adding them each to a motion planner
B) Receiving, storing, retrieving, and processing 1 line of gcode, then doing some simple math (about 10 operations), then adding it to a motion planner
Clearly, you're very attached to this idea, though; go ahead and try it. Make sure you use the same settings, except one with firmware acceleration enabled and gcode generated normally, and one with 100-1000x the commands for gcode acceleration.
Which do you think takes more processing time on a microcontroller?
A) Receiving, storing, retrieving, and processing 500 lines of gcode, then adding them each to a motion planner
B) Receiving, storing, retrieving, and processing 1 line of gcode, then doing some simple math (about 10 operations), then adding it to a motion planner
Clearly, you're very attached to this idea, though; go ahead and try it. Make sure you use the same settings, except one with firmware acceleration enabled and gcode generated normally, and one with 100-1000x the commands for gcode acceleration.
