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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.

This paper focuses on the design of the control structure which consists of inner loop controller employed for MR damper under impact loading by using computer simulation. The simulation is done by using MATLAB 7.0. The structure of the inner loop control for the proposed MR damper model uses a simple PI control to achieve the desired force. In this simulation, the MR damper model that has been validated with the experimental result is used to simulate the actual force that produced by MR damper. The performance of inner loop controller to track the actual force produced by MR damper by obtaining the several input functions which are half wave of sinusoidal, saw-tooth, square and random functions of desired force with the variation in pendulum mass of 15 kg and 20 kg are investigated. It can be seen clearly that under several input functions, the proposed polynomial model with PI controller has the good ability to track the desired damping force under impact loading.

Glass Fibre Reinforced Polymer (GFRP) has gained much attraction due to their outstanding physical and mechanical properties and it is widely used for various industry. The main objective of this present studies is to investigate the change of angle in taper round tube onto its energy absorption and to analyze the performance of taper round tube in energy absorption, crushing characteristics and its crashworthiness. Besides that, crushing characteristics of GFRP taper round tubes with different angles which are 0°, 2°, 4°, 6°, and 8°was determined using Universal Testing Machine (UTM) Instron series 3367. The energy absorption was calculated from the graph which is also the area under the load-displacement curve. Furthermore, the specific energy absorption was calculated by substituting the mass of the specimen into the specific equation (SEA = EA/mass). To find out the effect of crashworthiness of GFRP taper round tube, the crushing process and results were recorded as well. The highest energy absorption (EA) and specific energy absorption (SEA) were 506.812 kJ and 16.999.71 kJ/kg respectively. Lastly, the relationships between each parameter are discussed in the report. The design of the specimen and fabrication preparation plays a very significant role in quasistatic axial crushing test which must be decide carefully. From this experimental study, Glass Fibre Reinforced Polymer (GFRP) taper round tube with an angle of 6°is found to be the best for energy absorber as it has the highest energy absorption and specific energy absorption (SEA).

The overarching goal of this final year project are to design and fabricate a composite glass fibre reinforced with three different types of polymers (epoxy, polyester, and vinyl ester) followed by studying the crashworthiness characteristic under quasi -static load by using a universal testing machine. The composite specimens were fabricated by applying the hand layup technique by using woven glass fibre reinforced with the mentioned polymers as a resin. The crashworthiness characteristic of the composite tubes were evaluated by measuring the peak load, mean load, specific energy absorption, total energy absorption, and crush force efficiency with an addition of their fabrication costs. The failure mode and behavior of the tubes were studied and analyze by taking pictures of each crushed specimens and recording of their load-displacement curves when conducted the compression test. There were two types of failure mode identified through out the study on the specimens either local buckling or lamina bending. The vinyl ester composite was identified to be the most desirable since it gives the highest peak load, mean load, total energy absorption, specific energy absorption, and crush force efficiency values when compared to the other type of composite polymers. However, it was found that polyester had the lowest fabrication cost needed among the others. The whole project was successfully completed without any minor or major accident along the process from beginning until the completion.