Enhancing the rigidity of robot skin through the incorporation of plant growth

Abstract

Robot skin plays a crucial role in shaping both the appearance and physical properties of robots. While various types of robot skins have been developed in recent years, their physical performance tends to degrade with use despite being optimal during manufacture. In contrast, plants and animals naturally adapt and change their physical properties as they grow. In this research, we explore a novel concept of robot skin by incorporating plants and leveraging their growth capabilities. We focused on the rapid growth of sprouts, cultivating them hydroponically on soft materials. Through experiments using a compression tester on composite samples of the grown sprouts and soft materials, we observed an increase in compressive stress due to plant growth. Our findings demonstrate that plant-symbiotic skin has the potential to enhance rigidity through specific plant growth. Furthermore, we examined the relationship between the number of plants and Young’s modulus, which was calculated by linearly approximating the compression curve, and discovered that plant roots significantly affect Young’s modulus, particularly in the later stages of compression.