apply bending moment on a box?

You can apply a moment on any body, and it will act on the center of mass, yes.
I don't understand what means applying a "bending" moment though.
I don't think there is a need to change the point of definition of the moment, since it can always be reflected by applying moment +force.

Hi Chareyre,
thank you for your answer. And could you tell me the details about how the code would be?
is this
"class yade.wrapper.TorqueEngine(inherits PartialEngine → Engine → Serializable)

    Apply given torque (momentum) value at every subscribed particle, at every step.

    moment(=Vector3r::Zero())

        Torque value to be applied."

which was applied to particles.

by the way : how can I change the acting position?
thank you

Alvin

Yes, TorqueEngine can be used for that purpose. For a torque on body 10, for instance, you add this to engines:
TorqueEngine(ids=[10],moment=(0,1,0))

For changing acting position, again, it is useless (and not possible).

Hi Chareyre,
   I will try it. thanks a lot!
best regards
  Alvin