Study On Measurement Method Of Impeller Position And Pose Of Ventricular Assist Device

The heart is an important organ in the human body,which is responsible for pumping blood for other organs in the body.Problems with the heart will have a great impact on people's health.A typical example is heart failure,which is mainly caused by the insufficient ability of the heart to pump blood,which leads to the damage of people's health.The emergence of ventricular assist device brought effective solution for heart failure,ventricular assist device in China starts late,now due to more patients,medical conditions mature gradually,the development of ventricular assist device got rapid rise,and gradually to the miniaturization,minimally invasive implant development,the present ventricular assist device adopts the design of the third generation structure.The ventricular auxiliary device uses an electric motor to drive the impeller.During the driving process,blood is pumped to complete the function of the heart.Due to the circulation of blood in the device,this special working environment requires that we cannot use the traditional bearing impeller device.Because if we use the bearing device,the contact between different components will cause local pressure concentration,then damage the cells in the blood,and cause blood pollution.Therefore,our ventricular assist device adopts the way of magnetic levitation impeller to cooperate with the motor drive.In this case,the position change of the impeller determines the operating state and internal pressure of the ventricular auxiliary device,but the impeller position will change in multiple directions due to the impeller suspension.The detection of impeller position becomes a difficult problem.In this paper,based on this characteristic,we will design based on linear hall sensor and eddy current sensor ventricular assist device in the form of impeller position detection,this paper will analyze the simulation for electromagnetic fields inside the device,design the experimental project and the calibration device,demarcate the magnetic field signal intensity and eddy current sensor signal strength as the change of position,and do the corresponding regularity of summary.Finally,the actual experiment will be carried out.the measurement result characteristics will be analyzed.