I'm working on a motion control card PCB, which accelerates, coasts, and decelerates a motor to a desired position (accel and max velocity can also be specified).

Positioning is via an RS-422 encoder, which is decoded and fed into the MCU. The error between theoretical position and actual position is then subjected to a PID loop, and outputted as a bipolar +/-10v signal.

I need a motor which is supplied with a high-res RS-422 encoder and operates above 24v. The amplifier should accept the bipolar +/-10v signal.
Essentially I need to test whether the motion control card is actually working as it should. Does anyone have any suggestion on which motors, amplifiers meet my needs, and general advice?

Cheers

 

You don't say what size of motor, but for amplifiers/drives I use the ±10vdc analogue made by A-M-C or Copley Controls, AeroTech etc, these operate in the current/torque mode.
You may have to fit an encoder to a suitable motor, Is this a dedicated MCU system or is it custom programmed?
In the past I have always turned to Galil Motion cards that fit in a PC slot, although there is also stand-alone versions.
Max.

 

Could you provide some links please?
The PCB I'm designing consists of an LPC1700 MCU, which I have programmed.

 

Is positioning the most important selection criterion?

 

Is positioning the most important selection criterion?

I would say it's pretty important. Smoothness of motion is as well.

 

A two phase AC servo motor and amplifier could be used. A suitable encoder would have to be obtained.

 

Are you thinking of BLDC or DC motor, the Drives I quoted do both.
In fact the BLDC drives will drive either motor.
Max.

 

To be honest, I don't think it really matters. I just need to test whether my motion controller works. Anything that assert this is acceptable.

 

I would see if you can obtain an encoder of the type and resolution you want and do a search for a used servo motor, these often have rear shafts where either a through-hole encoder could be fitted or a shaft type using a coupler.
Max.

 

I would see if you can obtain an encoder of the type and resolution you want and do a search for a used servo motor, these often have rear shafts where either a through-hole encoder could be fitted or a shaft type using a coupler.
Max.

How about the drive?

 

Do a search on Ebay for Advance Motion Controls drive, the ones that include the power supply has suffix AC, others you have to provide the DC supply.
Where are you located?
Max.

 

Do a search on Ebay for Advance Motion Controls drive, the ones that include the power supply has suffix AC, others you have to provide the DC supply.
Where are you located?
Max.

I'm located in the UK.

 

Ok, I've decided to go for a 1hp VFD (single phase input, three-phase output) which accepts a +/-10v control signal. Does anyone have any suggestions?

 

I thought you wanted position control via an encoder/PID loop etc?
If you want to go with the three phase induction motor and VFD, then there is the bottom of the list/cheapest is the Huanyang from China, one step up from that that is a nice product and just a little more is the Hitachi HJ-models.
Max.

 

I thought you wanted position control via an encoder/PID loop etc?
If you want to go with the three phase induction motor and VFD, then there is the bottom of the list/cheapest is the Huanyang from China, one step up from that that is a nice product and just a little more is the Hitachi HJ-models.
Max.

I do, but don't many of these VFD's allow you to control via a +/-10v signal?

 

Yes, but not really conducive to PID positioning, although it can be done in a similar manner with an encoder option in the VFD.
The normal control method/use for a VFD is ±10vdc but just for velocity control, machine spindles etc.
Depends on your final intended usage. Servo positioning etc.
Max.

 

Yes, but not really conducive to PID positioning, although it can be done in a similar manner with an encoder option in the VFD.
The normal control method/use for a VFD is ±10vdc but just for velocity control, machine spindles etc.
Depends on your final intended usage. Servo positioning etc.
Max.

PID positioning will be done by the motion controller, so I would assume that it should still work. The +/-10v signal will be the result of the PID loop on the motion controller.

Do you have a specific VFD in mind? The ones I looked up didn't seem to have the +/-10v input.

 

VFD's have a 0-10v only usually the direction change is done by a contact closure input, FWD & REV. the encoder option is mainly for accurate speed control.
This is why I said they are not really conducive to servo type action as a servo motor and amplifier, as in motion control.
Max.

 

VFD's have a 0-10v only usually the direction change is done by a contact closure input, FWD & REV. the encoder option is mainly for accurate speed control.
This is why I said they are not really conducive to servo type action as a servo motor and amplifier, as in motion control.
Max.

So what would you recommend in this case?

 

You haven't really said if this is for a specific application or just for academic interest, if the former, then the mechanism criteria would be need to be known.
If the latter then something like this one 132684345863 on Ebay could be adapted and an encoder fitted to rear shaft.
You can get through-hole types or coupler mounted, the through hole are the easiest.
Unless you already have, you may have to search for the encoder you need, I have mainly used the quadrature differential type.
Or by RS422 do you mean this type, if so you need to find a one with suitable pulse count, usually at least 1200 p/rev which converts to 4800 p/rev when using the four edges.
There are also some nice motors with encoders on Ebay made by Sanyo-Denki
A suitably sized Advance Motion or similar drive would be needed.
Max.