Paper Title
Review of Recent Softness Display Devices and their Feasibility in Minimally Invasive Surgeries

Abstract
This paper aims to provide a review of recent softness display devices, which can help researchers find a literature review about the subject of up to date studies in one paper. Moreover, the degree of how convenient is it to use the presented tactile display inside the operating rooms is illustrated. In minimally invasive surgeries, surgeons are missing this precious sense of touch, which could lead to a misevaluation of the exact disease. Softness display devices are instruments that can provide the softness of a projected material to the user’s hand or fingertip. Various kinds of softness display and their biomedical applications are explained based on their working principle. For instance, softness displays based on rheological fluids, shape memory alloys, DC motors, pneumatic balloons, and electro-active polymers are all demonstrated in this paper. A definition of each type can be summarized as follows: rheological fluids are smart materials that can change their mechanical properties upon the existence of an external magnetic or electrical field. Shape memory alloy is those materials that are easy to change their shapes at low temperatures and they return to their original shape at high temperatures. Electro-active polymers are electro-sensitive materials that change their shape or size upon the existence of an external electrical field. As a result, this paper provides five various working principles of tactile displays intended to be used in minimally invasive surgeries and also present available studies for each type. Finally, the applicability of using these five tactile displays in the operating room will discuss. Keywords - Minimally Invasive Surgeries, Softness Display, Tactile Display, Shape Memory Alloys.