Feed rate very slow in 5 axis simultaneous

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AmitKumar171
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Joined: Tue Feb 20, 2018 7:35 am
Location: India
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Feed rate very slow in 5 axis simultaneous

Post by AmitKumar171 » Fri Sep 13, 2019 11:37 am

Dear Tom,

I am running a 5 axis g code in kflop board that is as follows.
N167 X0.4973 Y-5.5641 Z76.0197 A20.4252 C-148.8885 F2000
N168 X0.5097 Y-5.5923 Z76.0158 A20.0944 C-147.4391
N169 X0.5221 Y-5.6206 Z76.0118 A19.7754 C-145.9421
N170 X0.5345 Y-5.6489 Z76.0079 A19.4689 C-144.3973
N171 X0.5469 Y-5.6771 Z76.0039 A19.1756 C-142.8046
N172 X0.5593 Y-5.7054 Z75.9999 A18.8962 C-141.1644
N173 X0.5718 Y-5.7337 Z75.996 A18.6316 C-139.4773

But that g code is running at a feed of 20-40mmpm but i defined as F2000. So i want to get feed rate of F2000 for linear+angular move , so what changes i require for that in Kmotion init file and trajectory planner.

I tried using Inverse time feed rate also G93, that is also same (Feed rate of 20-40mmpm).

I have defined x, y, z as linear and a, c as rotary axis for the setup.

Waiting for your kind reply.
Thank You

AMIT KUMAR

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TomKerekes
Posts: 547
Joined: Mon Dec 04, 2017 1:49 am

Re: Feed rate very slow in 5 axis simultaneous

Post by TomKerekes » Fri Sep 13, 2019 5:47 pm

Please post your Trajectory Planner Settings
Regards,

Tom Kerekes
Dynomotion, Inc.

AmitKumar171
Posts: 28
Joined: Tue Feb 20, 2018 7:35 am
Location: India
Contact:

Re: Feed rate very slow in 5 axis simultaneous

Post by AmitKumar171 » Mon Sep 16, 2019 5:17 am

Hi tom,

here are the trajectory planner settings.
Screenshot (16).png
trajectory planner
Waiting for your kind reply.
Thank You

AMIT KUMAR

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TomKerekes
Posts: 547
Joined: Mon Dec 04, 2017 1:49 am

Re: Feed rate very slow in 5 axis simultaneous

Post by TomKerekes » Tue Sep 17, 2019 1:41 am

Hi Amit,

The issue is that the XYZ motion is very small (0.18mm) and the angular motions are quite large (C moves 9 degrees).

C axis Acceleration limit is set at 80 degrees/sec^2.

So the fastest possible motion is using maximum C Acceleration to move 4.5 degrees, and maximum C Deceleration to stop over 4.5 degrees.

The formula:

Distance = 1/2 Acceleration x Time^2

can be used to calculate the time required to accelerate (0.335 seconds) and decelerate (0.335 seconds) the C axis. Total Motion Time = 0.67 seconds.

Obviously moving XYZ 0.18mm over 0.67 seconds is not 2000mm/min. Rather it ramps to ~30mm/min then back to a stop to remain in sync with the angular axes.


Or looking at it another way: to move XYZ 0.18mm at 2000mm/min would only take:

Time = Distance/Velocity = 0.18mm / 2000mm/min x 60sec/min = 5 milliseconds.

Imagine your C Table attempting to rotating 9 degrees in only 5 milliseconds!


KMotion's Trajectory Planner goes through great effort to move in the optimal manner, while honoring all the constraints of your machine.

HTH
Regards,

Tom Kerekes
Dynomotion, Inc.

AmitKumar171
Posts: 28
Joined: Tue Feb 20, 2018 7:35 am
Location: India
Contact:

Re: Feed rate very slow in 5 axis simultaneous

Post by AmitKumar171 » Tue Sep 17, 2019 7:00 am

Hi tom,

What is the solution of this problem , or how can we use inverse time G93 for our KmotionCNC trajectory planner.

How to do trajectory planner settings ?

How to resolve my problem of slow motion of axes. ?

Is putting Radius =1 in trajectory planner makes all axes smoother ?

Waiting for your kind reply.
Thank You

AMIT KUMAR

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