Kinematic linkage simulator

YES!.. and no one talks about this which I find quite surprising.

I found a Youtube video which showed how to do it in Fusion360 and it works equally well in Shapr3D.

All you have to do is draw a four bar linkage with lengths specified (otherwise they’ll be stretchy and won’t behave like solid material.)
And you have to lock the two ground points of the linkage so they don’t move.

Then simply click on one of the two joints that do move, and drag it to make it pivot and see the whole linkage operate.
(Note that while you are dragging, you will see all of the dimensions, but when you click on the background, the dimensions go away and your linkage is in the new position.)

If you want to simulate a sliding joint like a hydraulic cylinder, just don’t specify the length of that line and it will stretch dynamically.

If you want to represent a bar as more than a single line, you can draw a structure of triangles of fixed lengths and even arcs with angle and radius specified, as long as the elements only reference that one bar. So those lines and arcs will act as one part.

It’s all about constraining the drawing to make the parts you want.
Then by tapping and dragging an endpoint of a bar (which is a joint of the linkage) you can see the full motion of the linkage.

It won’t plot the paths of joints but you can duplicate the parts to show the linkage in a series of positions.

And if you want see the linkage in a series of positions, you make a stack of linkages by copying the linkage in the Z axis. Unfortunately, once copied, you have to click on each line in each copy and lock the lengths again manually.
And you can make a gradient by sandwiching construction planes between the copies. The construction planes have a translucency which lightens the lines of each subsequent copy, when viewed parallel to the Z axis.

I hope all of that makes sense.
Someone should teach this in a Shapr3D tutorial.
(I suppose that could be me if Shapr3D is interested.)

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