  Recently, suction-based robotic systems with microscopic features or active
suction components have been proposed to grip rough and irregular surfaces.
However, sophisticated fabrication methods or complex control systems are
required for such systems, and robust attachment to rough real-world surfaces
still remains a grand challenge. Here, we propose a fully soft robotic gripper,
where a flat elastic membrane is used to conform and contact parts or surfaces
well, where an internal negative pressure exerted on the air-sealed membrane
induces the suction-based gripping. 3D printing in combination with soft
molding techniques enable the fabrication of the soft gripper. Robust
attachment to complex 3D and rough surfaces is enabled by the
surface-conformable soft flat membrane, which generates strong and robust
suction at the contact interface. Such robust attachment to rough and irregular
surfaces enables manipulation of a broad range of real-world objects, such as
an egg, lime, and foiled package, without any physical damage. Compared to the
conventional suction cup designs, the proposed suction gripper design shows a
four-fold increase in gripping performance on rough surfaces. Furthermore, the
structural and material simplicity of the proposed gripper architecture
facilitates its system-level integration with other soft robotic peripherals,
which can enable broader impact in diverse fields, such as digital
manufacturing, robotic manipulation, and medical gripping applications.
