In this paper, sandwich tube components which consist of thin-walled circular tubes with aluminium foam core are proposed as energy absorption systems. The sandwich tubes were laterally crushed under quasi-static loading conditions. The sandwich tubes were crushed under two types of indenters and exposed to three different types of external constraints. The collapsing behaviour and the energy absorption responses of these systems were investigated by nonlinear finite element analysis through ANSYS-LS-DYNA. Various indicators which describe the effectiveness of energy absorbing systems were used as a marker to compare the various systems. It was found that the sandwich tube systems compressed by cylindrical indenters particularly the unconstrained system (STCIU) and the system with inclined constraints (STCIIC) offered a very desirable force-deflection in which the force is almost constant in the post collapse stage. The employing of external constraints was noticed as a feasible method of increasing the SEA particularly when cylindrical indenter is used.