An aortic pressure observer for the Penn State electric ventricular assist device-a deterministic design

An aortic pressure observer for the Penn State electric ventricular assist device (EVAD) is developed. The pressure estimate is determined through the applied motor voltage (input) and the measured pusher plate position (output). The aortic pressure estimate will be used as a feedback signal of the EVAD´s cardiac output controller that will adjust the device´s beat rate to accommodate various levels of cardiac output demand. The gains of the pressure observer are deterministically optimized such that the optimal gains are independent of the initial pressure value. The gains are obtained by a method introduced by R.G. Jacquot (1984), which is extended from a single-state/single-output to a multistage/single-output formulation. In this method the deviations between the observed and the measured signals at finite number of instances are minimized