## 4 Conclusions  
The use of lattice structures has gained considerable popularity in various applications due to their advantageous weight-to-stress ratio. However, the choice of lattice structure must be carefully considered in accordance with the specific requirements of each application. This study focuses on the examination of three fundamental lattice structures cubic perimeter (CP), body face centered cubic (BCC), and face centered cubic (FCC) and the reinforcement structures created by combining these basic structures with a CP structure: BCC + CP and FCC + CP. These five structures and solid were fabricated by a photopolymer printer. In this investigation, the collapsing mode and stress-strain relationships were analysed using quasi-static testing with a cohort of experimental data. The results indicated that most of the lattice structures failed in a stretching-dominated mode, but the BCC failure mode was bending-dominated. The bending mode failure in the BCC was a result of stress distribution patterns as the two opposite pyramids joined at the peaks. The failure mode of the close-packed structure was also classified as stretching-dominated; however, it was assigned the particular category of sequential layer-by-layer collapse mode due to the high incidence of stress along the vertical columns and a more diluted stress distribution along the horizontal connections of each cell. The other structures were collapsed with stretching dominated. Under the quasi-static test, the null hypotheses were established as there were not any differences between the mechanical responses (relative density, relative stress and relative elastic modulus) with different lattice structures at a 95 per cent confidence level. Not only were all of the null hypotheses rejected with highly significant difference levels, but most of the responses mainly depended on the lattice structures; however, homogeneous results established that there was no significant difference in the relative density of the BCC and FCC. Therefore, the estimated weight of the BCC and FCC might not be statistically different, but they did not offer the same stress and strain because their architecture did not show identical responses at the specific compressive force, and one of the obvious results was different failure modes happening between these two structures, which resulted in the difference in relative stress and relative elastic modulus. Thus, this can result in inaccurate of the empirical model. It seems that most of the relative stress and relative elastic increased linearly with an increase of relative density, but there were exceptions with the CP and BCC. Under a quasi-stress test, the highest stress response was the FCC + CP, the strongest structure, with the smallest being the elastic modulus of the BCC, which was bending-dominated. A shock impulse test of closely 300 N (upto 1000 g) offered a clear picture of the differences between the lattice structures. The solid structure was obviously the strongest structure as it had a high rigidity; hence, it would be great to use in structural applications, but the lattice structure was lighter, with the highest shock absorption. In the case of the FCC + CP structure, there was an average shock force deduction of approximately 20 per cent, however this structure could save weight by roughly 85 per cent compared with the solid structure. Moreover, the average lighter weight of a lattice structure would be better operated if there was any significant difference in the shock impulse time in the same lattice structures, which can yield less difference in operating frequency. The other advantages of lattice structures were their shock compression insolation properties. It can be seen that solid structures had the poorest shock insolation properties as it had the highest transmissibility compared to the lattice structures. The impulse of the BCC + CP was the highest and this showed that the momentum change of the collision in this sample was the maximum.