Many methods or devices are used to obtain the plantar shape of the foot. These include molding the foot shape on a malleable material, plaster casting, optical sensing, contact measurement with sensors and so on. When a force is applied on a malleable material with a person's foot, it will deform to the shape of the footprint, which can thereafter be used to make an insole or other custom footbed. This method gives the natural shape of the foot with little resistance from the material. In reality, the natural shape of the foot is of little use due to the non-uniform bone and soft tissue structures in the foot. In other words, the deformations will be different in the different parts of the foot and the neutral shape will not match the varying stiffnesses of the foot. Methods such as plaster casting too have the same weakness as they give only the neutral shape of the foot. Optical sensing and contact sensor methods, even though very accurate, have their own weaknesses. They are ideal for obtaining the neutral shape of the foot but cannot be used to determine the shape inside a shoe or even in situations that simulate a shoe wherein the support surface should have the same parameters corresponding to a shoe.
Transparent material has been used to obtain the plantar shape of the foot but none of the previous methods are able to simulate all the footwear parameters together in order to determine the shape that is comfortable for the foot. Furthermore, most shoes, especially high-heeled shoes, which have such shapes are not comfortable for a person wearing them. Even though many different methods have been employed to determine foot shape, there is no robust method that allows the shape that is comfortable to be determined giving due consideration to the lengths, angles, and cushioning properties of the footbed surface.