###### Abstract  
The paper explores enhancing the mechanical behavior of stochastic lattice structures through a semi-controlled design approach. By leveraging the Gibson-Ashby model and predefined geometric routines, the study aims to optimize the mechanical response of lattice structures under compressive stress. Transitioning from stochastic to semi-controlled tessellation using Rhinoceros 7 software enables more predictable deformation behavior. Design parameters such as node formation, strut thickness, and lattice generation patterns are correlated with relative density to regulate stiffness and strength. Experimental validation using Acrylic Styrene Acrylonitrile (ASA) filament demonstrates the effectiveness of the proposed design model. The research emphasizes the importance of understanding internal mechanics by introducing a novel design approach to control geometry and topology arrangement in shaping lattice properties. By introducing a semi-controlled mechanism, the study seeks to improve the reliability and uniformity of mechanical responses in lattice structures. The findings highlighted the benefits of semi-controlled design approaches in achieving tailored mechanical properties. Specimens were compression tested in quasi-static uniaxial loading and showed that structures created with parabolic distribution dimensioned by \(\mathrm{h}_{\mathrm{p}}=0.5\mathrm{h}_{\mathrm{v}}\) originated the most reliable and most vital mechanical response compared with other design models, including typical Voronoi distribution. The improved mechanical response in between proposed design models constantly progressed by about 15% on average consecutively, starting from the parabolic distribution dimensioned by \(\mathrm{h}_{\mathrm{p}}=1.0\mathrm{h}_{\mathrm{v}}\) as the weakest ranked, up to the best one, dimensioned by \(\mathrm{h}_{\mathrm{p}}=0.5\mathrm{h}_{\mathrm{v}}\), even better than the typical Voronoi distribution. The proposed design model has introduced an entirely novel approach that significantly enhances the product's volume tessellation using routines that guarantee the validity of geometric and topologic entities. Uniaxial compression tests on lattice blocks highlighted the effect of the proposed approach on the mechanical properties of these structures, having shown particularly crucial repeatability and stability. Overall, the paper contributes to advancing the field of lightweight lattice structures through the novel design methodology and material characterization. v 2024 21 June 2024 6 July 2024 11 July 202  
morphology and functional design. Creating freeform geometry is a relatively straightforward routine, but incorporating it into the macro design of components, simulating natural conditions, and component working environments is quite challenging [2]. Parametric design has become more significant when it has become clear that additive-based technology can deliver complex-mathematically described geometric shapes like lattices with desirable quality defined by engineering or other rules [3]. Cell structures can take various physical forms, but lattices have outstanding properties over other types like foams, such as being lightweight, having high strength, absorbing energy, and reducing vibration. Regarding its uniqueness, natural cellular materials have ideally served as the original form to develop artificial structures made from various materials like foams, ceramics, and a wide range of plastics. The latter material is the most widespread among end users and broad industry since the FDM method covers most of the market. Although many papers have dealt with lattice structures made of metal foams and liquids, this paper deals with polymer material, which served in physical lattice creation [4]. Artificial lattice structures use basic unit cell shapes to make numerous repetition forms of interconnected cells. Repetition forms of lattice structures are realized throughout uniform and nonuniform lattice arrangements or, most frequently named, periodic and stochastic.