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In this paper, the effectiveness of the active bumper system to reduce the jerk of a vehicle during collision is discussed. The mathematical model is done by using MATLAB 7.0 to simulate a collision between a pendulum and a vehicle installed with the active bumper system. In the active bumper system, it consists of three parts which are magnetorheological(MR) model, inner controller and outer loop controller. The validated model is used to develop an inner loop controller by implementing a close-loop PI control to track the desired damping force through simulation. The governing equations of motions of vehicle collision and MR damper model are then integrated with the well known control strategy namely skyhook control. The performance of skyhook control is then compared with the vehicle with passive damper and common vehicle by using computer simulation in order to reduce the acceleration and the jerk of the vehicle during collision.

This paper focuses on the quasi-static response of the aluminum honeycomb core based on an experimental work. The load-compression and energy absorb characteristics of the out-of-plane aluminium honeycomb core are studied for three varieties of the core cell sizes which are 0.01905, 0.0127 and 0.00635 m. The crushing tests were conducted on the Instron machine with a displacement control of 5 mm/min. The initial part in the load-displacement graph shows linear elastic characteristic, followed by a non-linear elastic-plastic regime before it collapses. Based on the observation, the cell sized 0.01905 m shows the global buckling collapse, but the cell sized 0.0127 and 0.00635 m collapse as progressive buckling mode. The cell size 0.00635 m shows highest energy absorption due to it has the highest density and it collapses like the progressive buckling mode compared with the others specimen.

This paper focuses on the works to model the aluminium honeycomb with the effect of meshing size that implemented into a shell body of the honeycomb and frictional force that introduced into an interaction between the honeycomb and rigid plates. The model is performed by using ABAQUS 6.12 in the explicit environment. The honeycomb with 0.0127 m cell size is modelled and three types of mesh size which are 3 mm, 1 mm and 0.8 mm are analysed based on buckling mode and load-displacement characteristics. No friction coefficient is applied during simulation. From this simulation, 1 mm meshing size is the optimize value where the load-compression pattern graph is almost similar like the experimental result compared with others meshing size. But the buckling mode is slightly different compared with the experimental result where the bottom part of honeycomb made the contract or negative expand behaviour. In order to avoid this behaviour, the friction coefficient is introduced between the honeycomb surface and rigid plates surface. Two values of friction coefficient are tested which are 0.1 and 0.3. The findings is the frictional coefficient 0.3 and meshing size 1 mm are optimized values that can avoid the contract behaviour and the result of buckling mode is similar with the experimental result.