Need help with motorized positioning

[xshaper]

I would like to motorize these six surfboard holders they need to go up and down and front to back.There are 12 different size surfboards so that will be 12 locations for the top and 12 locations for the bottom.They just need to move to the right spot and stay when the router is cutting.They move now not automated.Is there a esey way to do this.
http://shapes4u.com/surfboardcnc.htm

Thanks
Mark

[Al_The_Man]

It depends what you call easy and how much precision you need in positioning and also how much resistance is place on them once they are in position.
This is known as point-to-point positioning, so it usually does not need any kind of exotic servo positioning.
The mechanics for instance could be done by pneumatic cyclinders and clamps, and the controller could be anything from relay logic and limit switch positioning, but the easiest way to control would be by a small PLC.
If you want to motorize them, you could also use steppers with a simple stepper controller that puts out a string of pulses for each position that is switch selectable.
Al.

[One of Many]

Would it be easier, cheaper and less complex to create interchangable nests for each model and leave the support posts in common location for instant indexing?

If you use a common origin on each fixture, between the top and bottom sufaces, then creating a nest to the same origin and geometry would be done once with nice repeatability for the next run down the road.

DC

[xshaper]

Al,
Thanks for the right name point-to-point positioning now I can do some looking. Here is a little more detail on what I have going on. The surfboard blanks are 5'9" to 12" long each one has a different rocker (bend in the bottom and top) The center point is always the same. The others change distance from the center and different heights to meet the surfboard. Here are some more pics one is a 10'6" and the other is a 6'1" I put the point-to-point positioning in red.
I am thinking of a self centering clamp at each end point that will lift the surfboard up and turn it over 180 .I put more pics to explain what I'm talking about.http://shapes4u.com/surfboardcnc.htm
What I have in mind for each point is 2-steppers on a rack and pinion 1 for the up and down and 1 for the front to back. If I go this way what is the best way to control the steppers.
Mark

DC
Take a look at the new pics and let me know if you think the nesting will work.I will need some more info to get what mean.Im new to all this stuff.
Mark

[One of Many]

Sure, nesting will work. Storing all your fixtures is the biggest head ache! You wouldn't need to automate the supports at all. I would have one base platform that could do all of the initial profiles for the top or bottom surfaces(if the beginning foam core blanks are near common size), then nest that finished side to cut the opposite side.

If I were to design it automated, I'd be looking at something addressable for up to 10 motors and plenty of I/O.

One option

If the center support could be stationary, you could have one screw for each end support horizontal position on one side of your base rail. Then one screw for each of the inner supports horizontal position on the other side of the base rail. Each vertical support could still use its own linear screw to adjust height and get clearance for flipping your part.

Then you could have stored position support programs(notepad .txt files) a PLC or a PC can send an RS-232 message for each motor controller to move. You would still need a seperate homing procedure on startup to reference the support structure.

Technically, you only need a rotary actuator on one end to flip it over, which could be handled by air to keep it simple.

Boards I have seen in the past were made with 2 part expandable foam. You could use the router to create molds and pour your own.....or use a finished board to make a mold for foam cores.

Lots of options.......if money is no object.

Al always comes up with cool solutions too.

DC

[xshaper]

I think I'm getting it. To do the positioning with steppers will I need to set it up the same way the 4 axes router is set up.Its own bob with 10 axes 10 drivers.Is this what you mean http://www.pmccorp.com/support/digital.php
I'm looking for a good way that stays in my budget money is an object.
No pouring maybe a EPS mold.

Mark

[One of Many]

If you look at the user manual to the link I posted, there are commands shown in the syntax the controllers use at the end of the PDF file. These are not as interconnected as your motion control that runs the router.

This type of stepper control is just an example. I do not know if these particular drivers are powerful enough for your needs. It was just to show a basic point to point motor control that is addressable although independent of each other.

I did not find any good examples of their programming. There is probably more info the the Control terminal software. I'd expect it to be something along the lines of:

The homing file:

{axis label 1-10}, Go Home, Reset direction,

or you may need to write the homing sequence.

The move file:

{axis label 1}, # of pulses, direction, ramping parameters, etc.
{axis label 2}, # of pulses, direction, ramping parameters, etc.
{axis label 3 and so on}, # of pulses, direction, ramping parameters, etc.

Each line in your text file sent via RS-232 would represent an axis and were it should move to. The respective daisy chained axis(preset in/on each driver) will only acknowledge the commands within its axis label line and ignore all others. These moves would be done relative to home, not current position, unless there were feedback from encoders and the move could be made incrementally. There are smarter controllers out there that can do this.

In order to create a move file, I'd expect there to be some sort of interface to jog each motor gently into position. Then record each position(pulses from home?) and put that data into its respective move statement. This could be run on a seperate PC or another RS-232 port on your router PC.

In your picture and the first post you mention 6 supports, but your depictions only show 5.

Another option


EPS molds are not cheap, as they use steam to expand the beads in a cast aluminum cavity. Your custom niche wouldn't benefit from that I suppose.

DC