[mactec54]

Well, I tried to search this forum for the term "JERK FACTOR" and the only thing that came up was your posts. SO........

It does help if you know what you are looking for

Not sure why you replied if you don't know what the problem is when using low count Encoders, ask in the real world you may get the answer if you know what to look for, some high end controls are now including Jerk control in there software to help over come this problem also, even with using high PPR Encoders this is the next step for software developers, here is a snip related to using a control that has advanced jerk control

.
Digital signal processing with computer circuits and software has encouraged control engineers to realize more capable control algorithms that today include jerk control. Today, "servos" can be defined as the use of negative feedback for the position, velocity, acceleration and jerk of inertial loads.

"Jerk" is the time rate of change of acceleration. It is the acceleration of the acceleration.
Jerk ramps the acceleration to smooth the velocity. Steps—sharp edges in command values—tend to excite mechanical systems to oscillate at their natural (resonant) frequencies. The bigger the step, the greater this tendency. If a system is not rigid relative to the performance that is expected of it, control over jerk can round the velocity corners. This reduces the amplitudes of the frequencies that excite resonance oscillation. As a result, acceleration factors can be set higher.

With higher acceleration factors, a tool can transition corners and traverse contours of constantly changing curvature at a faster rate, and do so more smoothly when the corners of both the longitudinal and lateral acceleration are ramped.

There are ( 2 ) things that can help to control machine "jerk" Encoder PPR and enhanced software, the control software is out of the range of most Hobby user but High PPR Encoders are not, any good AC servos have a minimum of a 16Bit Encoder, which is available and most Hobby user's can afford, this will help to smooth out a not so rigid machine and add a much better cut performance

The Performance difference between a 1000 PPR Encoder and a 65,536 PPR ( 16Bit ) Encoder you can see it, feel it, and enjoy the end results

[maxspongebob]

It does help if you know what you are looking for

Not sure why you replied if you don't know what the problem is when using low count Encoders, ask in the real world you may get the answer if you know what to look for, some high end controls are now including Jerk control in there software to help over come this problem also, even with using high PPR Encoders this is the next step for software developers, here is a snip related to using a control that has advanced jerk control

.
Digital signal processing with computer circuits and software has encouraged control engineers to realize more capable control algorithms that today include jerk control. Today, "servos" can be defined as the use of negative feedback for the position, velocity, acceleration and jerk of inertial loads.

"Jerk" is the time rate of change of acceleration. It is the acceleration of the acceleration.
Jerk ramps the acceleration to smooth the velocity. Steps—sharp edges in command values—tend to excite mechanical systems to oscillate at their natural (resonant) frequencies. The bigger the step, the greater this tendency. If a system is not rigid relative to the performance that is expected of it, control over jerk can round the velocity corners. This reduces the amplitudes of the frequencies that excite resonance oscillation. As a result, acceleration factors can be set higher.

With higher acceleration factors, a tool can transition corners and traverse contours of constantly changing curvature at a faster rate, and do so more smoothly when the corners of both the longitudinal and lateral acceleration are ramped.

There are ( 2 ) things that can help to control machine "jerk" Encoder PPR and enhanced software, the control software is out of the range of most Hobby user but High PPR Encoders are not, any good AC servos have a minimum of a 16Bit Encoder, which is available and most Hobby user's can afford, this will help to smooth out a not so rigid machine and add a much better cut performance

The Performance difference between a 1000 PPR Encoder and a 65,536 PPR ( 16Bit ) Encoder you can see it, feel it, and enjoy the end results

Putting other peoples writing and research forward as your own is called "Plagiarism". If you are going to use others work then you should provide an attribution or just link to their work so people know.

https://www.mmsonline.com/articles/u...g-jerk-control


As for the original question of using the IHSV60-30-40-48 in a direct drive configuration of a 2'x2' extruded aluminum gantry system driving 1605 ballscrews. I would say this. Searching this site revealed only one mention of this servo. That in itself is not a good sign. Also the only sellers that I could find on the internet were all over seas. Finally the only technical information that I could find was on the JMC website and it was almost entirely in Chinese.

If one was feeling adventurous you could buy one of the servo's and try it out. But I would not purchase all of the servos until you have tried one. You should also look at the tuning software, since it is a servo, it must be tuned. Although I did find the software on the JMC site, I did not want to run it on my PC.

In my opinion I don't think your application will be affected by the PPR of the encoders in these servo's. You mentioned the ClearPath servo setup for 800 PPR. I have 2 machines that are using these and I have no problem with uneven movement. Tuning the servo has a lot to do with this.

[mactec54]

Putting other peoples writing and research forward as your own is called "Plagiarism". If you are going to use others work then you should provide an attribution or just link to their work so people know.

You obvious can't read also, the post has nothing to do with Plagiarism get a life dude :wave:

What I posted I did not clam as my own, if you read you will see that I referred to it as a "snip" ( this is what I posted, here is a snip related to using a control that has advanced jerk control ) (wedge)

If one was feeling adventurous you could buy one of the servo's and try it out. But I would not purchase all of the servos until you have tried one. You should also look at the tuning software, since it is a servo, it must be tuned. Although I did find the software on the JMC site, I did not want to run it on my PC.

Now you are quoting what I have already posted :wave:

[HuguesP]

As for the original question of using the IHSV60-30-40-48 in a direct drive configuration of a 2'x2' extruded aluminum gantry system driving 1605 ballscrews. I would say this. Searching this site revealed only one mention of this servo. That in itself is not a good sign. Also the only sellers that I could find on the internet were all over seas. Finally the only technical information that I could find was on the JMC website and it was almost entirely in Chinese.

If one was feeling adventurous you could buy one of the servo's and try it out. But I would not purchase all of the servos until you have tried one. You should also look at the tuning software, since it is a servo, it must be tuned. Although I did find the software on the JMC site, I did not want to run it on my PC.

In my opinion I don't think your application will be affected by the PPR of the encoders in these servo's. You mentioned the ClearPath servo setup for 800 PPR. I have 2 machines that are using these and I have no problem with uneven movement. Tuning the servo has a lot to do with this.

Well i guess i should then leave the preliminary investigation for others. on the other side, there is some nice thing said on youtube about is little brother, the IHSV57-30-18-36. Sorotec.de sells it for 249 eur. and they sell a tuning cable,. I might leave this to more experimented people.

[mactec54]

Well i guess i should then leave the preliminary investigation for others. on the other side, there is some nice thing said on youtube about is little brother, the IHSV57-30-18-36. Sorotec.de sells it for 249 eur. and they sell a tuning cable,. I might leave this to more experimented people.

I would not give up on this as they are a good price and may work well on your machine build, as long as you get what information is needed that I posted in #9 you should be fine, contact the supplier and ask if it come's with tuning software and Cable

The motor size 400w is ok for your machine

Here is where you can get your Timing Pulleys from

https://www.sdp-si.com/products/Timi...leys/index.php

https://sdp-si.com/eStore/CenterDistanceDesigner

The GT-2-5 with 15mm wide is Ideal for what you need

In the designer select Metric and 5mm GT-2 and look at all the options, in most cases you have to Bore out the Timing Pulleys to suit what they are mounting on

Here is a Video of a 400w motor this machine works well and is a similar size to what you are building
https://www.youtube.com/watch?v=iTBr_rJXZSw