Hybrid steppers or servos?
- Mike_Eitel
-
- Offline
- Platinum Member
-
Less
More
- Posts: 1159
- Thank you received: 185
07 Sep 2020 22:14 #181183
by Mike_Eitel
Replied by Mike_Eitel on topic Hybrid steppers or servos?
Do you have original ledshine drivers? They have a tuning mode and also some warning when you loose steps. Did you tune them to your motors?
Please Log in or Create an account to join the conversation.
08 Sep 2020 07:58 #181218
by RoberCNC
Replied by RoberCNC on topic Hybrid steppers or servos?
No, they are Wantai drivers without any type of connector to communicate with the pc.
My God how much am I learning! what a lot of small mistakes made and things to improve !!!!
My God how much am I learning! what a lot of small mistakes made and things to improve !!!!
Please Log in or Create an account to join the conversation.
- Mike_Eitel
-
- Offline
- Platinum Member
-
Less
More
- Posts: 1159
- Thank you received: 185
08 Sep 2020 08:10 #181221
by Mike_Eitel
Replied by Mike_Eitel on topic Hybrid steppers or servos?
Pitty.
The original leadshine have a bit more configurable sw in it.
They can detect and optimize normal steppermotors. As when you measure phase and current with good resolution you can have something like a software resolver that knows precisely the position of your poles.
But they cost more then the copies
The original leadshine have a bit more configurable sw in it.
They can detect and optimize normal steppermotors. As when you measure phase and current with good resolution you can have something like a software resolver that knows precisely the position of your poles.
But they cost more then the copies
![;-) ;-)](/media/kunena/emoticons/wink.png)
Please Log in or Create an account to join the conversation.
08 Sep 2020 08:19 - 08 Sep 2020 08:24 #181223
by RoberCNC
Replied by RoberCNC on topic Hybrid steppers or servos?
It is clear, as they say, the one who buys well spends only once, very true in this case. These only have switches for pulse / rev, current table and an additional one for half current or full.
As the machinedude colleague said, it all started with fear, ignorance and doubts about whether I would be able to make it work, just having achieved it is an achievement for me, now it is to continue learning and improving![:) :)](/media/kunena/emoticons/smile.png)
I'm going to do the first tests with the dial indicator and the INI configuration parameters, to see what happens with 15mm / sec of acceleration.
As the machinedude colleague said, it all started with fear, ignorance and doubts about whether I would be able to make it work, just having achieved it is an achievement for me, now it is to continue learning and improving
![:) :)](/media/kunena/emoticons/smile.png)
I'm going to do the first tests with the dial indicator and the INI configuration parameters, to see what happens with 15mm / sec of acceleration.
Last edit: 08 Sep 2020 08:24 by RoberCNC.
The following user(s) said Thank You: Mike_Eitel
Please Log in or Create an account to join the conversation.
- machinedude
-
- Offline
- Platinum Member
-
Less
More
- Posts: 622
- Thank you received: 278
08 Sep 2020 09:37 #181227
by machinedude
Replied by machinedude on topic Hybrid steppers or servos?
one other thing that will cause lost steps is the drives getting to warm. when they over heat they do all kinds of crazy stuff. so the use of heat sinks and fans go a long way to keep this from happening. quick easy and cheap fix compared to throwing money at it until you get lucky and nail the problem down. usually just getting air flowing across them corrects the problem. but sometimes a heat sink is need as well.
The following user(s) said Thank You: RoberCNC
Please Log in or Create an account to join the conversation.
25 Sep 2020 18:26 #183753
by RoberCNC
Replied by RoberCNC on topic Hybrid steppers or servos?
Finally I have been able to do tests with a dial indicator and it does not repeat on trips, I have variations of hundredths, which I do not know if they fall within normality being steppers but for me it is the difference between having a 10 mm hole made and that it comes out of 9.5 mms.
As for what you comment on the machinedude drivers, I do not observe that they get especially hot, however I will try to put air flow in them with some fans.
Is there a way to fine-tune it or should I just assume it's what's with these motors?
As for what you comment on the machinedude drivers, I do not observe that they get especially hot, however I will try to put air flow in them with some fans.
Is there a way to fine-tune it or should I just assume it's what's with these motors?
Please Log in or Create an account to join the conversation.
- machinedude
-
- Offline
- Platinum Member
-
Less
More
- Posts: 622
- Thank you received: 278
26 Sep 2020 12:28 #183842
by machinedude
Replied by machinedude on topic Hybrid steppers or servos?
if it was lost steps it would probably not be a consistent .5mm error. which would lead me to believe it is something in the drive calculations or possibly a backlash issue. if it is backlash it would be .5mm every direction change on that axis. if it is a drive calculation the error should grow as the distance traveled increases.
The following user(s) said Thank You: RoberCNC
Please Log in or Create an account to join the conversation.
26 Sep 2020 20:10 - 26 Sep 2020 20:12 #183878
by RoberCNC
Replied by RoberCNC on topic Hybrid steppers or servos?
It is not a constant error, it varies with the travels. These have always been the same distance, what you say about varying the lengths traveled had not occurred to me, I will try it tomorrow.
I am also inclined to think that it comes from configuration errors, I have yet to enter the values that I have found in the documentation for Wantai drivers and try with different accelerations. Little by little, step by step hahahaha.
Thank you very much!!
Can a stepper always repeat zero?
I am also inclined to think that it comes from configuration errors, I have yet to enter the values that I have found in the documentation for Wantai drivers and try with different accelerations. Little by little, step by step hahahaha.
Thank you very much!!
Can a stepper always repeat zero?
Last edit: 26 Sep 2020 20:12 by RoberCNC.
Please Log in or Create an account to join the conversation.
- machinedude
-
- Offline
- Platinum Member
-
Less
More
- Posts: 622
- Thank you received: 278
26 Sep 2020 21:45 - 26 Sep 2020 21:47 #183888
by machinedude
Replied by machinedude on topic Hybrid steppers or servos?
steppers are usually 1.8 degrees or 200 step's per rev and based on the mico stepping they change in step counts. so if you have 1/10 mico stepping driver you now have 2000 sets per rev. so if you are dealing with a direct drive the pitch of your screws and the micro stepping are going to determine your configuration on that axis.
i think steppers are accurate if they are tuned right and also sized correctly but every thing in based off the math for the axis drive calculation. so they need set up over a decent distance to get good results with them.
since everything is open loop with a basic stepper you have to start with good components and you have to work all the mechanical problems out as much as possible so you get the best results possible.
rolled ball screws have lead inaccuracies and develop more backlash over time. then you have to watch out for connections coming loose as well. so in a nut shell you could have any number of issues throwing the axis out in the accuracy department so when trouble shooting work on the stuff that don't cost you money and try to narrow the root cause of the problem down, when your testing stuff you have to look for patterns and see if they repeat or seem random.
sounds like drive calculations and the error changing based on the distance. so think of the drive calculation error as something that will grow and get worse the further you move. if you have a big machine with a lot of travel when you fine tune the settings try to do your tests over as long of a distance you can measure accurately. indicators are good to get you pretty close but sometimes using as set of digital calipers works better to observe a longer travel distance.
i think steppers are accurate if they are tuned right and also sized correctly but every thing in based off the math for the axis drive calculation. so they need set up over a decent distance to get good results with them.
since everything is open loop with a basic stepper you have to start with good components and you have to work all the mechanical problems out as much as possible so you get the best results possible.
rolled ball screws have lead inaccuracies and develop more backlash over time. then you have to watch out for connections coming loose as well. so in a nut shell you could have any number of issues throwing the axis out in the accuracy department so when trouble shooting work on the stuff that don't cost you money and try to narrow the root cause of the problem down, when your testing stuff you have to look for patterns and see if they repeat or seem random.
sounds like drive calculations and the error changing based on the distance. so think of the drive calculation error as something that will grow and get worse the further you move. if you have a big machine with a lot of travel when you fine tune the settings try to do your tests over as long of a distance you can measure accurately. indicators are good to get you pretty close but sometimes using as set of digital calipers works better to observe a longer travel distance.
Last edit: 26 Sep 2020 21:47 by machinedude.
The following user(s) said Thank You: RoberCNC
Please Log in or Create an account to join the conversation.
27 Sep 2020 02:22 #183912
by rodw
Yes, provided the engineering has been done and the stepper is never asked to do more than what it can deliver. You should not be loosing steps. Its possible there is backlash in the system. One candidate is the misalignment coupling between motor and ballscrew. It needs to be able to handle the torque applied
Replied by rodw on topic Hybrid steppers or servos?
Can a stepper always repeat zero?
Yes, provided the engineering has been done and the stepper is never asked to do more than what it can deliver. You should not be loosing steps. Its possible there is backlash in the system. One candidate is the misalignment coupling between motor and ballscrew. It needs to be able to handle the torque applied
The following user(s) said Thank You: RoberCNC
Please Log in or Create an account to join the conversation.
Moderators: piasdom
Time to create page: 0.116 seconds