EMC2 + Gecko 540 - 6-8 axis robot

[avongil]

Hi guys,

I'm looking to build a small desktop robot and it looks like EMC2 is a good solution to control a 6+ axis robot. I have two questions,

1 - I want to use two gecko 540s for a total of 8 possible axes. Is this possible with the EMC2. Can it use two parallel port cards? What cards do you recommend that are easily installable in ubuntu?

2 - I need all joints to have an angular g code input. Im pretty sure this is possible with EMC2 manually setting up the hal. is that correct?

If anyone sees any issues or better solutions, please let me know before I get too deep!

Thanks!

[Big John T]

EMC2 can control up to 9 axis. It can use up to at least three parallel port cards I think. I know for sure it can use two cards. Take a gander here:

http://wiki.linuxcnc.org/cgi-bin/emc...atics_machines

and pop on the #emc IRC channel or use this link to talk to developers and users

or try our embedded java client on this page to connect to the IRC channel.

http://www.linuxcnc.org/content/view/4/8/lang,en/

John

[chester88]

EMC can use up to 8 parallel ports. How will you select which of the 8(?) motors gets power from the the 2 Geckos or are you using some sort of mechanical transmission?

[acondit]

Originally Posted by chester88 EMC can use up to 8 parallel ports. How will you select which of the 8(?) motors gets power from the the 2 Geckos or are you using some sort of mechanical transmission?

Chester,

I am not sure what you are asking. With G540s power is hooked up to each G540 and the power to the motors comes from the driver inside the G540. The hal file would have to tell which G540 is controlled by which port and which motor is controlled by which PP pins from that port.

Alan

[chester88]

I meant that you said EIGHT axis and TWO drivers/motors. The math doesn't add up. How do you move 8 motors with 2 drives.

[acondit]

Originally Posted by chester88 I meant that you said EIGHT axis and TWO drivers/motors. The math doesn't add up. How do you move 8 motors with 2 drives.

The Gecko G540 is a complete breakout board with 4 individual drives built in. So, 2 - G540s yields 8 drives.

Alan

[chester88]

Ah now I see - you are using the new math ok sorry obviously I don't know anything about G540s.

[avongil]

Nice. Thanks for the info. 1/2 way done with the robot solid models, so the project is moving along quite well. I think I will go the EMC2 route since I can add two more axes in the future if necessary.

I will throw up a web site soon so you can see what I am talking about.

[Crevice Reamer]

Originally Posted by chester88 Ah now I see - you are using the new math ok sorry obviously I don't know anything about G540s.

The tiny G540,

http://geckodrive.com/product.aspx?c=3&i=14469

is a revolutionary new product that was invented and developed by Mariss Freimanis and chronicled real-time right here on the Zone, in this thread:

http://www.cnczone.com/forums/showthread.php?t=51083

It is a long, but fascinating read.

CR.

[avongil]

Here is my progress so far:

http://www.alvarogil.com/cadcam/robot/index.html

[avongil]

Do you think I should incorporate reductions? I plan on using 4 nema 23 motors for J1 - J4 and 2 nema 17 motors for J5 and J6. It will be a fairly light robot since it will be mostly plastic, but I am a little concerned that it will not be smooth at its limits.

What do you think?