The increasing demand for sustainable materials has accelerated the development of Natural Fiber Reinforced Polymer Composites (NFRPCs). However, while their mechanical and environmental performance has been studied, little attention has been paid to how users perceive these materials through touch and how such perceptions influence their acceptance in product design. This study addresses this gap by exploring the integration of haptic perception into the evaluation of NFRPCs within the framework of circular design. A haptic experiment was conducted with 116 participants, who evaluated rotomolded NFRPC samples differing in polymer matrix, fiber type, and sieved-fiber size. Drawing on the frameworks of Material Driven Design and Soft Metrology, the research combines objective surface characterization with subjective sensory assessment to identify how tactile experience shapes perceived material quality, functionality, and aesthetic value. Results indicate that user perception is more strongly influenced by matrix and fiber characteristics than by surface roughness alone. PLA-based composites were generally perceived as higher in quality and more aesthetically appealing, whereas PE-based composites were associated with functional use and lower perceived quality. The study demonstrates the relevance of integrating experiential and technical evaluation methods in early design stages. This approach contributes to developing perceptually engaging and sustainable materials, fostering user-centered innovation in circular product design.
Narganes-Pineda et al. (Sun,) studied this question.