Hi there, I am currently trying to simulate a frontal collision of a spaceframe steel chassis with a rigid wall. The chassis has a honeycomb impact attenuator mounted to the front of the chassis via a steel plate. I have homogenised the honeycomb into a solid element equivalent to save computation time. I have modelled the steel plate as a shell with 4mm thickness. I am having issues attaching the steel plate to the beam elements I have used for the chassis tubes. Is there a constraint or coupling which will join these pieces together as if they were welded. Thanks!