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View Full Version : Testing Leadshine closed loop stepper system.



JAZZCNC
06-10-2012, 01:06 AM
Thought I'd post my first findings on a Lead shine closed loop digital stepper system I have had the chance to mess with courtesy of Gary at Zapp Automation. . . Cheers.

I've actually had this system for quite a while now but not yet had chance to use this motor/drive on a working machine due to Illness/family/work matters interfering.!! . . . . So for now it's just a simple bench test with a video to show.

Ok well first off I've got to say I'm very very very impressed and I believe looking at the future of modern Digital stepper systems.!! . . . . Yes at the minute they are still quite expensive in relation to your standard Analogue stepper system but that will and is already starting to rapidly change has digital drives become more common.
It won't be very long before these Hybrid servo systems are down to such price levels that they will easily be affordable to the DIY user and it's not going to be very long IMO before Digital drives do to analogue drives what broadband did to dial-up.? . . . make them 99% extinct.!

These Hybrid servo stepper systems will certainly be giving the low end servo systems a very hard time and for such machines that require the positional accuracy of servo's but not necessarily the high speeds they will be a far cheaper and easier solution.

For the DIY router/Mill users they will be a god send and no longer will you worry about missed steps or positional loss.

No longer will the wide dual motor driven gantry router machines have to worry about running out of sync or a stalled motor while the other continues on it's merry way trying to twist the gantry and ball-screws into a twizzler's.!!

No longer will they have to de-tune motors just to have a stable speed to avoid racking caused by missed steps.!!

I'll report back when I eventually get time to strap onto a machine and get stuck into the setup software. (Don't hold your breaths thou it won't be anytime soon.!!) Another very useful feature digital drives provide, allowing far more versatility for those that want to play and tweak the most performance out of there systems.

Anyway enough bleating and watch and see for your selfs here.!! . . . .


http://www.youtube.com/watch?v=ZMZdCcLQc4M&feature=youtu.be

irving2008
06-10-2012, 08:46 AM
Very impressive. Whats the resolution of the encoder on that? Thats where the bulk of the cost is, the electronics themselves are reatively simple.

JAZZCNC
06-10-2012, 09:50 AM
Very impressive. Whats the resolution of the encoder on that? Thats where the bulk of the cost is, the electronics themselves are reatively simple.

Believe nothing special 1000 count I think.?

irving2008
06-10-2012, 10:01 AM
Hmmm, I would have thought more if they were to resolve the microstepping. 1/8 step would need 1600 counts/rev, wouldn't it? Were you microstepping that in the test?

JAZZCNC
06-10-2012, 10:09 AM
Was set at 800ms in Mach.

To be honest this setup is straight out the box and i've had very little time to fiddle. I need to get into the drive software parameters and play around but the only PC I've got with RS232 port has expired so need to get USB converter so can use laptop.

JAZZCNC
06-10-2012, 10:49 AM
Irving how do I get the video to show in the post.? Can you show or alter the first post so it does it please.?

m_c
06-10-2012, 11:24 AM
Looking good.

Now since you've obviously got nothing to test it properly on, just send it to me and I'll test it properly ;)

JAZZCNC
06-10-2012, 02:19 PM
Now since you've obviously got nothing to test it properly on, just send it to me and I'll test it properly ;)

Oh I've plenty of use's for it just life keeps getting in the way.!!

Lee Roberts
07-10-2012, 12:51 AM
Thanks for taking the time to do this review/video Dean; I have a couple of questions for you...

1. What would make the fault signal handy for reporting back to Mach? my initial thoughts are you could use it to stop mach and also the spindle?, is there anything else it could be used for/to do? How would we use it to control a bunch of relays for things like the spindle, coolant and so on?

2. What/why would there be a massive mechanical advantage from this system when coupled to a lead screw?

Cheers,
Lee

JAZZCNC
07-10-2012, 05:49 PM
1. What would make the fault signal handy for reporting back to Mach? my initial thoughts are you could use it to stop mach and also the spindle?, is there anything else it could be used for/to do? How would we use it to control a bunch of relays for things like the spindle, coolant and so on?

The alarm signal can sink or source 20Ma current @ 24v so it could be used for either with the correct relay.


2. What/why would there be a massive mechanical advantage from this system when coupled to a lead screw?

There's no advantage from this particular system compared to standard system other than the digital drives being better at handling the current than analogue.

But when I said mechanical advantage I referring to the amplified forces of the rotational torque to linear force that the pitch of the ball-screw gives and therefore a mechanical advantage and the fact I wouldn't have been able to hold the Ball-nut like I did the pulley on the motor shaft if connected to ball-screw or any other linear motion translator with a ratio.!!

Ger21
13-10-2012, 05:39 PM
If they offered a Nema 23 size motor in the 3.5-4Nm range, I'd seriously consider using these on my new router.