Modelling, design and control of a new seat-cushion for pressure ulcers prevention

Abstract

Pressure ulcers are a frequent complication in patients having limited activity and mobility (e.g., elderly people, spinal cord injury patients, people with disabilities, etc.). The aim of this work is the conceptual design, modelling and control of a new seat cushion for pressure ulcers prevention. The whole system (constituted by the seat cushion equipped with a real-time pressure mapping with closed-loop control) is designed to identify the critical points on the human skin, before pressure ulcers creation, and to be able to distribute the contact pressure between the human and cushion avoiding wound creation. The seat cushion is constituted by soft air-cells actuated by air flow. To define the shape and size of the soft air-cells, finite element simulations are carried out, analysing the internal volume reduction with external loads application to reproduce the variable stiffness. The data obtained by finite element analysis are used to simulate inflation and deflation of the soft bubble air-cells. Finally, the control systems of a single air-cell and of the whole cushion are designed and simulated. The novelty of our work consists in the conception of a seat cushion able to recognise higher and lower risk zones of pressure ulcer generation on the human skin and to provide compensation automatically. This work can therefore be considered in line with the sustainable development goals recently launched by the EU Commission.

The Research on Soft Pneumatic Actuators in Italy: Design Solutions and Applications

“…The last layer is drill valve is fixed to the layer by a nut to allow for air inlet and outlet. Mannella et al [59] have made APs consisting of a cylindrical (or hemis tomeric membrane clamped to a rigid lower block (Figure 9c). The membra fabricated in liquid silicone that was poured into a special mold and place chamber to reduce the likelihood of air bubbles.…”

“…Mannella et al [59] have made APs consisting of a cylindrical (or hemispherical) elastomeric membrane clamped to a rigid lower block (Figure 9c). The membranes have been fabricated in liquid silicone that was poured into a special mold and placed in a vacuum chamber to reduce the likelihood of air bubbles.…”

“…Intens occlude the blood vessels and causes the concentration of the surrounding soft tissues. Recently, Mannella et al [59] cushion consisting of four concentric surfaces, each associa The surfaces are constituted by many cylindrical APs (diam thickness = 1.2 mm). Each level surface is connected to two and the other to deflate the actuators, and to a pressure sens ion-body interface pressure.…”

“…Intense and prolonged pressure can occlude the blood vessels and causes the concentration of toxic substances that damage the surrounding soft tissues. Recently, Mannella et al [59] designed a prevention ulcer cushion consisting of four concentric surfaces, each associated with a different risk zone. The surfaces are constituted by many cylindrical APs (diameter = 30 mm; height = 65 mm; thickness = 1.2 mm).…”

Modular Pressure Redistribution Cushion with Proprioceptive Soft–Rigid Hybrid Actuator

“…[12][13][14] In recent years, numerous cushions for redistributing pressure have been developed, which can be classified into passive and active pressure redistribution strategies. [15,16] Passive pressure redistribution cushions utilize a variety of features and materials, including foam, gel, air cells, or a combination thereof, to reduce localized pressure points by evenly distributing the individual's body weight over a larger surface area. [17] Passive pressure redistribution cushions may not offer optimal relief for all users, given their inherent inability to actively adapt to the unique contours, weight distribution, and movements of individual bodies.…”