| Cellular mechanics is an advanced field in the developments of biomechanics, and it is also an important component of tissue engineering. Great efforts have been put on studying how the mechanical forces affect cell behaviors, and therefore the mechanical loading system in the experiments of cellular mechanics became the key-point technology. Studying the present researches on the flow chamber systems, we could find that the present experimental systems could not supply quasi-physiological pulsatile flow field for vascular cells, and cellular mechanics analysis under this condition have not been carried through. So this dissertation focused on developing an experiment system that can supply quasi-physiological pulsatile flow. And some primary experiments for validation were performed This dissertation includes the following aspect:1. Using the virtual instrument technology I designed and accomplished a platform for measuring and controlling the pulsatile flow experiments, and the core component was the data acquiring system. Used in the cell pulsatile flow experiments and other experiments the platform has exhibited the characteristics of good adaptability and convenience. So it proved that the measuring and controlling system based on the virtual instrument architecture which is reusable and convenient to construct the experimental system do supply a good method for the experiment of cellular mechanics.2. We developed a line motor and its power amplifier, which acted as the driving mode of the cell pulsatile flow experiment. This method can generate the pulsatile flow conveniently, and also can avoid polluting the cells through isolating the driving system and the cycle loop of the cell experiment. The line motor can be controlled conveniently and do has good stability, and furthermore it has a wide range of frequency response which is satisfied the requirement of the experiment of pulsatile flow.We developed a modularized programmable gain amplifier, which can adjust the pressure, temperature, and displacement signals. The programmable function can enhance the precision of the signal transform, and the modularization design made the construction and use of the* This research work is supported by the National Nature Science Foundation (No. 19602012)amplifier convenientWe designed fluid heater for the cycle loop and its controller, which made the cells grow in the proper environment and ensured the biological activities of the cells in the experiment3. We designed and constructed the distributing step motor controlling system. A monolithic processor was use as the stop motor controller, and the asynchronous serial port acted as communication interface between the upper controlling computer and the step motor controller. The system established an effective controlling method for the cellular mechanics experiments, and it has the good expansibility.4. We set up a image capture system for acquiring cell microscope images. In the cell experiments, in order to observing the cell behavior conveniently we need to capture the cell images regularly, the system can reach the aim successfully.5. We modified the traditional observing mode to the remote observing method by using LAN. This method can reduce the effects on cells caused by lab assistants, and made the researchers master the course of the experiment.6. Using the UML and component technology, we programmed the software for the experimental system. The UML method made the software architecture clearly and easy to implement Using component method enhanced the reusability of the software, and made the virtual instrument software development more reasonable.7. The experiment system could add shear loads which changed with the pulsatile flow to the cells, and the biological activities of the cell could be preserved in the process of the experiments. The construction of the system supply a method for adding shear stress to cells and do has significance to the development of the experimental methods of cellular mechanics.
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