imposition constraints in assembly design

[seven90]

hello everyone, i have a little doubt. i have recently started using the assembly module design of catia v5 and i have a problem with the constraints, i can place the objects as i want to bind them, but then if with the manipulator the egg one of the parts for example by turning it around a board this wheel as if the other components did not exist passing them without problems despite having imposed (on the surfaces that pass) a contact bond. why does this happen?
i also tried to block the set but nothing. in particular i am trying to assemble a piston formed by the head of the piston the biella and the pin that crosses the head and the biella of the piston. i don't think it's so complex yet the three components can rotate intersecting others as if nothing were.

 

[marcofa]

the manipulator moves the piece without taking into account the constraints.
with the command "manipulation" you have the option ,m to set, to maintain the constraints
Mar

 

[seven90]

Here. Maybe you can help me with something else. I had assembled the piston with the camshaft and then wanted and followed an animation. Obviously I have to impose that the shaft rootes, and rotates but does not drag behind the cylinder despite the constraints. thanks in advance

 

[marcofa]

Obviously there are no correct constraints.
simple example tree, biella, piston,carter/cylinder
fixed cylinder/cylinder
tree constraint coincidence axes and offset with carter
biella constraint coincidence axis handle and offset
piston constraint coincidence axes pin head of biella and offset; also coincidence piston axis and cylinder

each joint must be bound totally leaving only free the desired movement (rotation for the shaft, linear shift for the piston etc.)

At this point with the manipulation command and active constraints option, you can move everything by turning the motor shaft.
if you want to create a simulation the speech is more complicated and you have to go to dmu kinematics

 

[seven90]

Now I try to do it again and see if I impose all the constraints or not.