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data set not kinematically determinate

data set not kinematically determinate

data set not kinematically determinate

(OP)
Dear members,

I've a chain with many parts connected with joints (spherical, revolute, cylindrical).

I've imposed motion on some of them, so my system has one DOF(verified).
Input and output members are connected with 2 point-curve constraint to move on 2 paths.
Dynamic simulation is ok.
I reach what I want.

But I like to perform only a kinematic simulation, with no mass and inertias involved.

When I set kinematic simulation, I receive this error message:

ERROR:      The data set is not kinematically determinate, yet a kinematic analysis
   has been requested.  STATICS and DYNAMICS are two possible choices for
   the analysis mode.  KINEMATICS is not valid in this context.

I hope somebody can help me...
Many thanks!
Francio

RE: data set not kinematically determinate

(OP)
ok, I changed joints in input and output and it worked. It seems that with ptcv constraints in input and output the system is not kinematically determinated,  even if IC about displacement and velocity are setted.

So I sobstituted the pctv joints with spherical joints and translational joints, and put a motion on the input translational joint.

The result is the same, but with pctv it didn't work.

I don't wnow why...

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