This paper presents an experimental study to determine the behaviour of composite panels, made of polyurea sprayed on Kevlar or Dyneema support layers, under blast and fragments produced by an improvised explosive device (IED). The fragments used for tests were steel bearing balls of 8 and 10 mm propelled by a plastic explosive charge and bullets cal. 7.62 mm, type Full Metal Jacketed Armor Piercing (FMJ AP) and Hollow Point Boat Tail (HPBT), with impact velocity greater than 500 m/s. To determine the fragments attenuation, their velocities before and after the impact with the composite panel were measured and compared. In order to assess the blast attenuation, the reflected pressures measured by two face-on sensors, one of which was covered by the composite panel, were compared. Also, to explain the behaviour of composite panels under blast, the shock polars of materials in the panel�s composition were plotted. The results have shown that the composite panels have a low rate of attenuation of fragment velocities but a very good ability to attenuate the pressure and impulse associated with the shock wave.

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To protect the personnel of the intervention units operating in high-risk areas, it is necessary to introduce (autonomous/semi-autonomous) robotic intervention systems. Previous studies have shown that robotic intervention systems should be as versatile as possible. Here, we focused on the idea of a robotic system composed of two vectors: a carrier vector and an operational vector. The proposed system particularly relates to the carrier vector. A simple analytical model was developed to enable the entire robotic assembly to be autonomous. To validate the analytical-numerical model regarding the kinematics and dynamics of the carrier vector, two of the following applications are presented: intervention for extinguishing a fire and performing measurements for monitoring gamma radiation in a public enclosure. The results show that the chosen carrier vector solution, i.e., the ground vehicle with six-wheel drive, satisfies the requirements related to the mobility of the robotic intervention system. In addition, the conclusions present the elements of the kinematics and dynamics of the robot.

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Terrorist events that occurred in the last years changes the global security policy, imposing additional safety measures for building design. Therefore, the protection of access routes should be considered by using protective doors to resist to impact and explosions effects. This paper presents a thorough analysis on establishing a proper configuration to ensure a minimum level of blast protection for metallic doors used for government and military buildings. The analysis includes experimental tests and numerical analysis performed on a 1/3 scale model. Seven different sandwich-type configurations were tested according to specific requirements of actual standards. Each door was successively mounted on a metallic frame, horizontally placed, and a spherical plastic explosive charge, at a standoff distance of 35 cm, was detonated. The deformations were measured on each side of the door, offering the valuable data of their strength capacity and also of the dissipation energy level. The door with a honeycomb interior configuration resulted to be the optimal solution. The numerical results showed a good correlation with numerical ones, permitting the further development of a full-scale model.