Preliminary development of an advanced modular pressure relief cushion: Testing and user evaluation

Smart seat cushion feasibility pilot study: automated interface pressure modulation of individuals with spinal cord Injury

This study investigates the functionality and feasibility of a novel smart seat cushion system designed for wheelchair users with spinal cord injuries. The cushion, equipped with air cells that serve as both sensors and actuators, was tested on 24 participants for its real-time pressure mapping, automated pressure redistribution, and pressure offloading functions. A commercial pressure mat was concurrently used to validate the cushion's pressure modulation functions. Additionally, the perceived comfort of the cushion was evaluated using General Discomfort Assessment (GDA) and Discomfort Intensity (DIS) scores, which provided insights into participants' overall comfort and discomfort levels. Real-time pressure profiles generated by the cushion resembled commercial pressure mat readings. During tests with individuals with spinal cord injury, the cushion was able to dynamically generate and display the real-time pressure profile of a seated individual with strong precision (correlation to commercial pressure mat: r ranging from 0.76 to 0.88), providing effective input into pressure modulation functions. Pressure redistribution algorithms eliminated peak pressure and reduced the overall pressure at the interface. Pressure offloading algorithms automatically identified the regions with the highest interface pressure and subsequently relieved the pressure from those areas. User feedback showed that the cushion was comfortable after redistribution and offloading. This work demonstrated the feasibility of an advanced smart seat cushion system for wheelchair users with spinal cord injuries. The cushion was capable of redistributing pressure evenly across the seating surface, ensuring user's comfort. Additionally, it identifies and eliminates high-pressure points, further improving comfort and reducing the risk of pressure injuries.

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

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.