| Along with the auditory and visual feedback in virtual/distant environment applications in recent years, force feedback has been increasingly utilized. The reason is its positive effect on task completion time in tele-operation and virtual reality applications that require force feedback. The force feedback that serves human haptic sensory mechanism providing distributed or point forces to a part of human body are respectively referred to as tactile feedback and haptic feedback. Perhaps, one of the most significant fields of haptic feedback devices, i.e. haptic interfaces, is medical training that allows the use of a virtual patient. Common research fields are surgery simulation, required mechanisms, software development and improvement of performance measures of existing simulators.; This research is aimed at realizing preliminary angioplasty simulators, assessing design requirements derived from these initial devices and creating necessary instrumentation to determine pre-identified vital parameters for further angioplasty simulator realization. As a continuation of an ongoing project, passive designs, Haptic User Interface (HUI) and modified version of HUI, have been designed and built. Evaluation of the devices has been accomplished to assess the essential parameters for the ideal simulator and conceptual design has been undertaken. When designing ideal simulator, particular attention is paid to active/passive actuation emphasis and decoupling of two forced axes of the simulator for independent force feedback. Because of the lack of parameters in the light of completed interfaces, experimental one-degree of freedom PTCA (Percutinuous Transluminal Coronary Angioplasty) simulator and torquer force transducer (TFT) has been built to measure present forces of the operation and several required performance characteristics. Of particular interest for realizing an angioplasty haptic interface are ranges of forces experienced in the surgery and effect of friction-inertia compensation. Linear system modeling, control algorithm in state space and transfer function form has been performed for one-axis angioplasty simulator. TFT, which is similar to an actual tool used in PTCA to manipulate the catheter or guide-wire, has been designed to be applied during real surgery environment. However, ethical considerations prevented the experimentation with live patient, yet trial of the device will be able to be done in further research in a simulated environment. |
