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I need help in doing a (probably) very simple animation. I want a body to free-fall into an exact location and angle. I've already arranged the "rigging body" physics for the gravitation fall, and now I want to set the location and angle for my body to land on. How can I achieve this?

Thanks in advance!


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I want the body to fall down, but instead of simply hitting the ground randomly, end at a specific location. I've tried animating it using key frames, but it's way too much work and doesn't have that "realistic touch".

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  • $\begingroup$ Hi and weclome! Unfortunately no simple question since any kind of simulation approximates real world physics and is dependant on a lot of different properties so it might be more suitable eg. inverting the gravity for this specific simulation... Could you please add a sketch to illustrate what you'd like to achieve? Also I'm not sure whether a rigid body simulation is the right choice and would give the result you expect since the simulated parts are rigid. Does that make sense for a human body? $\endgroup$ – brockmann Oct 30 '20 at 12:58
  • $\begingroup$ there's no image attachments in the comment, so I uploaded one as an "answer" below. $\endgroup$ – user110062 Oct 30 '20 at 14:14
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    $\begingroup$ Blender can do this quite well in fact. It can guarantee a ball or other object/body will not only land on a small target but come to a stop when it gets there. With Blender however there is usually some 'work' involved. Will have to dig out the Blend file(s) and get back later. (2am here at the mo. (yawn) $\endgroup$ – Edgel3D Oct 30 '20 at 15:19
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In both examples the object of the exercise was to have a cube dropped with physics and still have it ending up exactly on target.

This was achieved by baking the physics actions and manually adjusting (biasing) those resultant sequences to get the cubes to where they're supposed to be.

To do this, the graph editor was used to drag the X/Y axis' keyframes as a whole up and down in the Editor's Y axis. (one axis at a time and with only the appropriate keyframes selected)

Select the keyframes and press keys G Y to ensure no inadvertant drift to the left or right.

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For those without Graph editor experience...

Set up a test file and give a cube horizontal momentum then switch it's physics to Dynamic to drop it to a ground plane that has passive physics.

Use the Graph editor's keyframe handles to adjust the cube's X/Y axis Bezier curves into a straight line (end of the slope) at the drop frame. (where you switch from Animated to Dynamic physics) This will ensure the cube has inertia at the switchover and will slide across the plane when it lands.

Once it's landing, bouncing, & sliding as desired, bake the entire sequence from frame 1 to where it comes to rest. (in the bake panel, tick all boxes and enter the frame range required)

This will snapshot every frame in the selected range and store the action as keyframes, but with a catch!

Baking will remove constraints that might exist on the object but not do the same with the physics.

Consequently - Don't play the animation just yet !

Instead, manually switch off the physics, and also get rid of the two redundant physics strips left behind in the Dopesheet.

With them gone it's safe to play the baked frames and carry out the Graph editor biasing.

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