Low cost 6 axis USB motion controller

[Xerxes]

Hi folks,

I have been silently developing a motion controller which plugs into USB and provides 6 SPI channels for VSD drives. It provides far more advanced alternative to step/dir. It finally unleashes the full power of servo drives.

Target specs (may change):

• Update rate 6x2500 Hz
• On-board data buffering to eliminate PC real time requirements
• All kinds of motor/drive feedback data available to control software
• Cost less than a drive
• 6 general purpose I/O or analog inputs
• Open source programming library
• Reduces cable mess
• Possible to tune drives without unplugging any cables or opening cover
• Comes with pre-assembled flat flex cables, just snap them in

It can be used to make point-to-point apps as well as continuous motion tracking (suitable for CNC).

[ger21]

Will you have a plugin for mach3 support?

[Xerxes]

Gerry,

At the point of release there probably isn't support in any CNC software for it. Mach plugin seems technically possible, but I have to take a better look on it.

For beginning we may develop simple open source example program that runs G-code with it.

[antichip]

Depending on the price point I could see this being used as an alternative to pluto-p or mesa cards. I'm sure EMC support would be straight forward for smarter people than I.

[hunserv]

Seems a good idea!
So do I get it well, this would be a motion card, which does not generate step/dir signals for 6 servodrives, but rather outputs data on the SPI bus for 6 VSD-s?
On what level would it communicate with the VSD drives? (position commands, speed commands, or whatever we select on software?)

Can it calculate something, or it just outputs data from its buffer in a nicely timed fashion what the pc software pre-calcuated?

[JerryFlyGuy]

Tero, is it going to have a bunch of i/o as well? Will it be a closed loop feed back system?

It sounds like you could have another winner!

J

[Xerxes]

hunserv, I'm also EMC2 user and would very much like to see SPI drive support in it one day. However, EMC developer mailing lists discussions don't give much hope for USB device support. Would need lot of changes in EMC. However, some FPGA card could do the job instead. SPI gets finally documented so anyone can implement the support.

Jerry, loop is closed in drives. USB card is quite dumb itself and just sends commands to drives. There is 6 I/O's on board (can be used as analog inputs too)

[dansutula]

Xeres,
So would this device replace or eliminate the need for a breakout board?
Is it compatible with the VSD-A (first production lot) drives?

[Xerxes]

If drives are controlled thru USB card, then you don't need anything else than just power supply and motors.

It is compatible with any VSD-A thru the stamp sized adapter that comes with USB tuning cables, so yes. VSD-E has 6 pin connector for SPI so it doesn't need adapter.

[JPW]

Any more good news?

[Xerxes]

Originally Posted by JPW Any more good news?

Progress has been made in programming library. There will be open source motion control library that won't even be GD specific but anyone is free to use it in competing products, too. Hopefully it will gain some popularity (at least in CNC) and it would be supported in control softwares.

I'm also researching possibilities to make the device EtherCAT compatible in addition to USB.

[ftec]

Originally Posted by Xerxes Progress has been made in programming library. ... Hopefully it will gain some popularity (at least in CNC) and it would be supported in control softwares. ...

Mach plugin would certainly be something to have asap. Is this card as fast as Smoothstepper meaning no soft gearing for servos would be needed if it could be used with Mach?

(I've had nearly a months delay in setting up my system because of waiting warranty replacements for my BOB card (same charge pump output TTL voltage level issue in two cards so far). I would welcome an option to see BOBs go away.)