Using ShapeOKO as a Pick & Place machine

Karl
Posts: 75
Joined: Tue Apr 17, 2012 4:01 am

Using ShapeOKO as a Pick & Place machine

Post by Karl » Sun May 20, 2012 11:16 am

Don't know if "Design Ideas" is the right group to put this in, but here it goes.

I have some plan of using my ShapeOko as a manual/semi-automatic Pick & Place machine. Will be used mainly for placing small IC:s like MLF, SOT etc.
Planing to use the software from Openpnp (http://code.google.com/p/openpnp/)

Here is a rendering of the finished machine
rendering.jpg
rendering.jpg (115.36 KiB) Viewed 5336 times
* The tube to the left is a USB pen microscope camera bought from Ebay. (Not finished with the mounting yet)
* The vacuum head is also bought on Ebay. (It was very hard to use manually but I think it will be good to use with this machine.)
* The stepper motor for rotation of the head is a NEMA-8.
* Endstops are a variation of the mechanical endstop from Makerbot Industries (will release design files later)

This is how far I have come with the head:
p_and_p_head_mount.jpg
p_and_p_head_mount.jpg (76.74 KiB) Viewed 5336 times
Now I mostly waiting for my inventables kit to be shipped!

Rendering was done with EagleUp (to get the PCB renedered in Sketchup), Sketchup and Kerkythea.
http://www.akafugu.jp
ShapeOko #313

domon
Posts: 2
Joined: Mon May 14, 2012 11:10 am

Re: Using ShapeOKO as a Pick & Place machine

Post by domon » Thu Jun 28, 2012 8:37 pm

Karl, can you say something more about the vacuum head? Can it be used with elements as small as 0603 resistors?

Karl
Posts: 75
Joined: Tue Apr 17, 2012 4:01 am

Re: Using ShapeOKO as a Pick & Place machine

Post by Karl » Fri Jun 29, 2012 12:49 am

Hi domon,

I just received my ShapeOko in the mail yesterday and have been busy building it together...

The vacuum head was a cheap one bought on ebay (similar to this one: http://www.ebay.com/itm/QS-2008-Pick-an ... 3cc3ab4372)
As the pen is straight it is very hard to use manually but I think it will be perfect for this semi-automatic application. I will tape the hole and use some additional tubing and a solenoid valve to control the vacuum.

I think the head is fine with 0603 but might need some optical help for placing them reliably.

More info to come when I get everything up and running.
http://www.akafugu.jp
ShapeOko #313

Karl
Posts: 75
Joined: Tue Apr 17, 2012 4:01 am

Re: Using ShapeOKO as a Pick & Place machine

Post by Karl » Thu Jul 05, 2012 1:24 am

After successfully use the vacuum solenoid to pick up components I have started thinking about the next step.
I would need a board to drive a additional A axis for rotating the vacuum head and perhaps another stepper on the y-axis for more reliable movement.

So I came up with this design of a board with two stepper controllers and one solenoid control to hook up to the original stepper shield.
stepper_vacuum_breakout.png
stepper_vacuum_breakout.png (86.89 KiB) Viewed 5047 times
http://www.akafugu.jp
ShapeOko #313

edwardrford
Posts: 1250
Joined: Mon Apr 09, 2012 5:40 pm
Location: Dixon, IL
Contact:

Re: Using ShapeOKO as a Pick & Place machine

Post by edwardrford » Thu Jul 05, 2012 1:40 pm

I like that design Karl, it's clean and efficient. (btw: what did you use to model it?)

My only thought about the rotating head is wondering if it would be easier to use a hobby servo? I'm assuming the most rotation you would need would be 180 degrees, in which case most hobby servos could handle that. You would/could also drop the need for an extra driver as the servos would connect directly to arduino.

Any reason why that approach wouldn't work?

-Edward
Shapeoko 1 #0 - a couple of upgrades.
Shapeoko 2 #0 - a couple of upgrades.
Shapeoko 3 #2 - Stock

Karl
Posts: 75
Joined: Tue Apr 17, 2012 4:01 am

Re: Using ShapeOKO as a Pick & Place machine

Post by Karl » Thu Jul 05, 2012 2:13 pm

Thanks, the model is exported from Eagle CAD with the brilliant EagleUp plugin[1] into Sketchup. The individual components are drawn in Sketchup directly with the aid from the data sheet of each component. A while ago we did a story about using Sketchup for PCB design[2].

Probably a servo would be easier yes, but we need almost 360 degree of freedom as some parts has to be in a certain direction, such as ICs, diodes, polarized capacitors etc.
Not quite sure if a servo could give us that?

[1] http://eagleup.wordpress.com/
[2] http://gweb-sketchup-showcase.appspot.c ... ino-x/view
http://www.akafugu.jp
ShapeOko #313

PLHS54
Posts: 60
Joined: Sun Apr 22, 2012 7:36 pm

Re: Using ShapeOKO as a Pick & Place machine

Post by PLHS54 » Thu Jul 05, 2012 7:06 pm

Here is a full 360 degree servo, http://www.sparkfun.com/products/9347

zimmer62
Posts: 81
Joined: Fri Jun 22, 2012 4:51 pm
Location: Lansing, MI

Re: Using ShapeOKO as a Pick & Place machine

Post by zimmer62 » Thu Jul 05, 2012 8:16 pm

PLHS54 wrote:Here is a full 360 degree servo, http://www.sparkfun.com/products/9347
With 360 servos like that they are continuous, I'm not sure you can just pick an angle and it goes to that. In fact I'm pretty sure you need some sort of feedback loop to pull that off.

Anyone have an experience getting continuous servo motors to go to a specific angle and stop?

All of my servos function in one of two ways. PWM to control speed (on the continuous ones) or PWM to control angle on the normal ones.

You could use a gear to convert a 180degree movement into a 360degree movement on a servo that was not continuous. However I'd still go the stepper route being that most hobby servos seem to have some on and off jitter that might be a problem.

Digitalmagic
Posts: 123
Joined: Sat Jun 23, 2012 8:47 am

Re: Using ShapeOKO as a Pick & Place machine

Post by Digitalmagic » Thu Jul 05, 2012 8:33 pm

zimmer62 wrote:Anyone have an experience getting continuous servo motors to go to a specific angle and stop?
You would need a quadrature encoder (closed loop mode). Clock and Direction are outputted.
From there, you could feed the arduino with them, and actuate the servo PWM accordingly.
s/o #650 - Wish my digits are ... magic!

Aaron Seltzer
Posts: 46
Joined: Tue Apr 10, 2012 4:33 am

Re: Using ShapeOKO as a Pick & Place machine

Post by Aaron Seltzer » Fri Jul 06, 2012 12:30 am

Most 360 servos are actually continuous rotation, with no position feedback. PWM sets speed, not position.

A winch servo is designed to do 3.5 rotations (3.5x360degs).

http://www.servocity.com/html/hs-785hb_ ... tions.html
http://www.servocity.com/html/s3802_arm_type_sail.html

You could gear that down and get a bit over 360, with PWM commanding... Or just use as is...

Or, you could get a standard 180 servo, and 1:2 gear it to get you the 360. You don't need much torque...

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