Miniaturised Soft Manipulators with Reinforced Actuation Chambers on the Sub-Centimetre Scale

Fibre-reinforced soft robots are often considered in the design of fluid elastomer actuators, to counter ballooning and potential bursting when exposed to high levels of pressure. They also enhance deformation and navigation through confined spaces. These attributes are critical in applications such as minimally invasive surgical (MIS) procedures that use sub-12 mm diameter trocar ports. While soft robots with fully reinforced actuation chambers have not yet attained this level of miniaturisation, this paper outlines the fabrication and characterisation of miniaturised soft manipulators with reinforced actuation chambers on the sub-centimetre scale (i.e., less than 10 mm). Two robots are presented with diameters of 9.5 mm and 7.8 mm. They have four pneumatic actuation chambers per robotic segment, with a free central working lumen. Additionally, two robotic segments are serially connected to enhance dexterity and flexibility. This research advances the miniaturisation of soft manipulators with reinforced chambers and an inner free lumen, enhancing their use in applications within confined and unstructured environments.