The overall objective of the proposed SBIR Program is to develop a novel physiologic control system for use with the rotary centrifugal MiTiHeart LVAD that employs a magnetically suspended impeller with a hybrid active/passive magnetic bearing support system wherein only the thrust bearing is actively controlled. The fundament premise forwarded is that the available system data sets will provide a self-sensing and redundant method of controlling pump output while avoiding the detrimental conditions associated with negative flow or suction/cavitation at the inlet. It is expected that the pump operation will be different for a normally operating pump and one undergoing negative flow or suction at the inlet due to the lower inlet pressure and hence fluid forces acting on the rotor. By monitoring pump operating parameters a novel and reliable pump speed control system will be developed that avoids inlet suction/cavitation and/or negative flow. The goal of Phase I project is to demonstrate the feasibility of using the measured pump parameters for pump control through a parametric study that would lead to the development of the appropriate control scheme. The goal of Phase II will be to evaluate the control scheme using established computer simulation models to refine the Phase I control algorithm and controller for the MiTiHeart LVAD. The controller and algorithm will then be validated through instrumented non-pulsatile and pulsatile mock loop in vitro testing. Final Phase II validation testing will be accomplished through in vivo animal studies. The proposed high-speed machining center will be used by dentists and/or dental laboratory technicians for fabrication of ceramic dental restorations. The proposed machining center will be designed with an innovative integrated air-driven, high-speed, precision, spindle/motor assembly to allow high machining rates while ensuring low potential for machining damage: thus, enabling rapid fabrication of low-damage dental restorations by machining. ? ? ?
