Is there a way to a link or chain actions within a block

[fraser.whyte]

I have created a block in AutoCAD of an excavator with multiple moving parts and I want to know if there is a way to link the parameter / actions so two type of actions can work together.

The model I have attached only has two moving parts:

1. The arm     -    rotation

2. the piston -    polar stretch

They both have different rotation points which need to remain the same. I am moving the two parts independently and I want to know if I can link the second Polar-stretch grip with the rotation action. reducing my workload etc

[MMcCall402]

Um, no model attached.

[fraser.whyte]

Here is the dwg

[MMcCall402 · Accepted solution]

The issue it that the polar distance 3 for the hydraulic cylinder needs its grip moved in a arc around the same center point as the boom.  A stretch acting is needed to move just that end of the parameter, but a rotation action, like the one that rotates the boom won't accept a stretch action.  You can facilitate this by putting in a Point parameter with a stretch action.  Set the rotation parameter to rotate the point parameter and the point parameter's stretch action to stretch the polar distance parameter.  Set the Point and Polar distance parameters chain setting to Yes. The result is a stretch along an arc.

[MMcCall402]

Fun block.  I'd like to see it when its done.

[fraser.whyte]

Hi 

I tried to follow your tasks to duplicate what you did but the rotation point for the piston base keeps on moving. 

Is there a way you can attach a video or step by step images.

Thank you for you help

Fraser

[MMcCall402]

Not able to do a video right now.  Work thing.

The process I used was to make a point parameter with a stretch action. Make the stretch action window over just the end of the polar parameter to be moved and then select the polar parameter as the action set.  Set the polar parameter's property for chain action to Yes.   Test this.  The point parameter should now operate that end of the polar parameter.

Next, edit the selection set for your current rotation action to include the point parameter.  Then set the point parameter's chain action setting to yes.

This sets up a two step chaining of actions.  The rotation action rotates the point parameter that in turn stretches the the polar parameter.  The end result is a rotational stretch around a point that's different than the polar parameter's other end.

[fraser.whyte]

Thank you, I have got it to work. I am experience some issues with the grips on the piston / polar stretch misaligning once out of the block editor. 

So the piston rotation points are in a different location. It remains in the correct place within the block editor

[MMcCall402]

Sometimes you need to reinsert a fresh instance of the block for it to take on the changes that have been made and operate correctly.