Enhanced design of a robotic bed with pressure redistribution and lateral positioning functions for pressure injury prevention

Patients confined to bed for extended periods are highly susceptible to pressure injury, which can lead to severe complications and prolonged hospitalization. The redistribution of pressure through continuous repositioning of the patient’s body is essential to mitigate this risk and ensure that excessive pressure is not sustained on any specific body part. In a previous study, the authors proposed a robotic bed capable of pressure redistribution; however, it lacked the patient side-lying positioning capability recommended for preventing pressure injury. In this study, we propose an improved robotic bed designed to prevent pressure injury. The developed prototype consists of 10 independently driven segments and incorporates 70 pressure sensors, with each segment having a lifting capacity of up to 60 kg. The segments are powered by linear electric actuators, and the driving mechanism combines a scissor mechanism and a pin-in-slot mechanism, enabling not only linear motion but also rotational motion to facilitate pressure redistribution in the supine position and to reposition the patient into a side-lying position. Kinematic analysis of the proposed mechanism was performed, and experiments with the developed prototype achieved a linear displacement of 89.5 mm and a rotation angle of 19.2°, thereby experimentally verifying its ability to achieve pressure redistribution and side-lying positioning. If its clinical efficacy is demonstrated through future clinical trials, the proposed robotic bed may provide a technological basis for future pressure-injury prevention strategies, subject to clinical validation.