Step-Direction vs Analog Command vs CW/CCW Signals

No I am not in a hurry,

I have looked at those drives a few years ago when I brought the robot. I did not know they would support the Yaskawa enocders.

Now I have to be sure exactly what they will support. Yaskawa has two divisions for its servo motors, Robotics and Industry. A general purpose Yaskwa servo is different to the type they use in their robots As far as I know that is what went on in the early 90's when the robot was made.

I have the specs somewhere but it outputs a very specific pulse that only the drive made for that motor can read.

I really hate proprietary hardware and I am trying hard to move all of my machinery away from that. If I fit new absolute encoders and use new drives at least I can be sure if it fails I can repair it easily.

The DMM servo drives I have brought are only $218 USD each and the absolute encoders as $55 each. Its just a matter of fitting the encoders to the motors and tuning the servo with the drive.

I would hate to think what the Yaskawa encoders were worth brand new. They are very well made and look very expensive. I am sure they are high quality but do you really think there would be much real world difference in performance? Especially now I am ditching the proprietary controller and using LinuxCNC?

Hi thefabricator03
I have a slightly silly question, the robot you have is quasi-serial kinematics, I think genserkins and pumakins only support serial kinematics, am I still wrong? It's just a question I ask myself.

regards
Chimeno

thefabricator03 wrote:

No I am not in a hurry,

I have looked at those drives a few years ago when I brought the robot. I did not know they would support the Yaskawa enocders.

Now I have to be sure exactly what they will support. Yaskawa has two divisions for its servo motors, Robotics and Industry. A general purpose Yaskwa servo is different to the type they use in their robots As far as I know that is what went on in the early 90's when the robot was made.

I have the specs somewhere but it outputs a very specific pulse that only the drive made for that motor can read.

I really hate proprietary hardware and I am trying hard to move all of my machinery away from that. If I fit new absolute encoders and use new drives at least I can be sure if it fails I can repair it easily.

The DMM servo drives I have brought are only $218 USD each and the absolute encoders as $55 each. Its just a matter of fitting the encoders to the motors and tuning the servo with the drive.

I would hate to think what the Yaskawa encoders were worth brand new. They are very well made and look very expensive. I am sure they are high quality but do you really think there would be much real world difference in performance? Especially now I am ditching the proprietary controller and using LinuxCNC?

Are you sure the Yaskawa motors will work with the DMM drives?

Well I spoke to the company and they assured me it would work,

Last night I hooked up the motor to the drive, powered it on and was meet with smoke spewing from the motor.

I only brought one drive and encoder to test this out so no a great loss and I have been thinking I would replace the motors anyways.

Now I just need to find some suitable motors and drives.

chimeno wrote:

Hi thefabricator03
I have a slightly silly question, the robot you have is quasi-serial kinematics, I think genserkins and pumakins only support serial kinematics, am I still wrong? It's just a question I ask myself.

regards
Chimeno

Hi Chimeno,

As far as I know LinuxCNC has support for up to 9 joints, I was assuming that it would be able to handle 6. I have seen other robots of similar constuction being controlled my Machinekit,
machinekoder.com/machinekit-ros-industrial-robot/

So I assumed LinuxCNC would be able to handle it. I will post my results when I get to that stage with my robot, Now I need to source new motors and drives.

tommylight wrote:

9 Axis, much more joints, i think, in version 2.8 and 2.9 of Linuxcnc .

Yeah thats right 9 axises, and each axis can be comprised of multiple joints.

Tom, What are your thoughts on a 6 axis robot retrofit with Linuxcnc? For this robot there really is no other option. It was made in 1991 and the ERC contoller is very much antiquated.

thefabricator03 wrote:

Well I spoke to the company and they assured me it would work,

Last night I hooked up the motor to the drive, powered it on and was meet with smoke spewing from the motor.

I only brought one drive and encoder to test this out so no a great loss and I have been thinking I would replace the motors anyways.

Now I just need to find some suitable motors and drives.

Some not so expensive ac servo and drives.

I have used these on a few machines. I just bought 8 sets with cables and got them for $173.00 each set with 25 foot cables.

bevins wrote:

Some not so expensive ac servo and drives.

I have used these on a few machines. I just bought 8 sets with cables and got them for $173.00 each set with 25 foot cables.

I have been looking at those on that site, I have contacted a few sellers on Alibaba that will sell direct to me. One thing I hate about them is the chinglish that comes in their manuals. I need brakes on all the motors and that drives prices up. But I will more than likely use China brand ac servos.

How long have you been using them for? Any problems with tuning? Do they come with tuning software? Is the software in English?

Off topic but I brought a Wecon HMI last year. Its made in china and its cheap but its all the budget for the project allowed for. Quality is good. Software is really hit and miss. The basic layout is good but simple things like the menus at the top of the screen, simple english words were spelt wrong. Does not affect performance but it did annoy me a little.

thefabricator03 wrote:

bevins wrote:

Some not so expensive ac servo and drives.

I have used these on a few machines. I just bought 8 sets with cables and got them for $173.00 each set with 25 foot cables.

I have been looking at those on that site, I have contacted a few sellers on Alibaba that will sell direct to me. One thing I hate about them is the chinglish that comes in their manuals. I need brakes on all the motors and that drives prices up. But I will more than likely use China brand ac servos.

How long have you been using them for? Any problems with tuning? Do they come with tuning software? Is the software in English?

Off topic but I brought a Wecon HMI last year. Its made in china and its cheap but its all the budget for the project allowed for. Quality is good. Software is really hit and miss. The basic layout is good but simple things like the menus at the top of the screen, simple english words were spelt wrong. Does not affect performance but it did annoy me a little.

Well, I didnt say it was easy to setup. I have a manual in english for them. I also have a spreadsheet with what needs to change to get them to tune properly. Tuning was a bear with these, but one machine was done over two years ago and never had an issue with them and they are used commercial production.

There is no tuning software available for these. You can pay more and get that but there is no port on these to connect with software. It has a plastic blank on the port.

Basically, you have to shutoff the internal loop or it just ends up fighting with linuxcnc. And some parameters need changes.... Certainly worth the effort at those prices.

Oh and I got brakes on two of the eight, (Z-Axis), and I negotiated them for free.