Development of the Actively-controlled Beds for Ambulances

During transportation by ambulance, the inertial acceleration acts on a patient when an ambulance decelerates or turns a corner. Such acceleration often gives a supine patient physical stress such as blood pressure variation and body sway, which results in pain or a feeling of discomfort. To reduce this undesirable effect of the acceleration, the actively-controlled bed, which controls a posture of the bed to cancel the inertial acceleration by the gravitational acceleration, was developed. This paper gives an overview of its development, including control system design and performance evaluation.