Patients who experience extended stays in the hospital often spend a good amount of time in a hospital bed. This prolonged non-ambulatory state can cause bedsores or decubitus ulcers. Traditionally, hospital personnel employ various techniques for the movement and displacement of patients, however this is sometimes not possible, or it could be dangerous for some patients and cumbersome for the hospital.
Advances in the medical equipment manufacturing technology allow the use of smart beds and mattresses, which intelligently distribute the pressure throughout the patient’s body to prevent ulcers from forming. The smart beds utilize multiple low pressure sensors in order to sense variable load displacement, and adjust the zones for optimal weight distribution across all body parts.
To ensure long-term and short-term usability of these smart beds, pressure sensor calibration and verification is a critical step in the manufacturing process. Typically these are low pressure MEMS sensors within the 0.18 psi (5 inches of H20) to 2 psi (55 inches of H20) measurement range, and can vary in accuracy from 1% FS to 0.1% FS. The verification process requires functional testing of the pressure measurement electronics with the MEMS sensor to ensure the specifications are met.
Since a single smart bed employs multiple pressure sensors, the test and verification times are critical to the manufacturer. A pressure controller could be the ideal reference to calibrate these sensors, as it is capable of reducing the total test time significantly through automation. Some pressure controllers could also provide simultaneous testing by way of two channels along with high measurement accuracy to ensure the reference to device under test accuracy ratio is better than 4:1.