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This parameter works only with “Create chain from roots” from the “Mode” option. The mode of operation is exactly the same as with “Rigids A” and “Rigids B”. The nodes, entered here, will act as the chain's root link, and they will set the coordinate system for the “Rigid B” connected to it. Both active and passive rigid bodies can act as “Rigids C”.
Free X
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| Y
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| Z
All of these parameters have exactly the same functionality: if set to “Yes”, the node's axis will not be influenced by a MultiServo and can act completely freely. You will also see that the corresponding “Blocked [XYZX|Y|Z]” parameter become inactive and vice versa, because an object's axes cannot be free and blocked at the same time. Another case is when an object's axes are neither free nor blocked. Here, the MultiServo will act, but it will be limited to the adjusted forces and powers.
A rising balloon is a nice example for free objects. In this case you want the balloon to perform a motion along a vertical axis, but the motion in horizontal directions should not be influenced by the MultiServo's forces – only by wind or collisions with other objects. To achieve this behaviour, a “MultiServo Position Linear” node will be used with a target in the vertical axis (Y or Z – this depends on your scene setup). To allow horizontal movement, the appropriate axes (“Free X” and “Free Z”/”Free Y”) must be set to “Yes”.
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Blocked X | Y | Z
These parameters depend directly on “Free [XYZX|Y|Z]” and can influence each other. When “Blocked [XYZX|Y|Z]” is set to “Yes”, the servos will act with infinite force and power on the appropriate axis. With “No”, forces and power will be limited to your settings under the “Forces” panel. When an axis is blocked, it cannot act freely anymore and therefore the corresponding “Free [XYZX|Y|Z]” parameter will be inactive and greyed out.
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