Development of the pressure and share forces control system and its blood flow analysis to solve the mechanism of pressure ulcers

据说，压疮不仅是由压力引起的，而且是由对人体的分担力引起的。在本研究中，我们开发了一种机械系统，该系统具有向人体的骶骨部分施加压力和分担力的机制。该机构有两个电机提供两个力和三个称重传感器来测量力。因此，该系统可以利用称重传感器的数据和电机来控制压力和共享力的值，从而有可能给人体一定的可控负荷。此外，该系统还可以使用激光多普勒流量计测量受力部位的血流量。利用这个系统，我们做了一些实验来测量当我们施加一定的力时的血流量。我们给压强6kPa，10kPa，14kPa这些压强加上4.5牛的合力。我们利用血流量数据，通过反应性充血来评估每种情况的损害程度。通过这些实验和分析，我们得到了以下结果。反应性充血按压力值越大，对人体的伤害就越大。当我们同时施加压力和分担力时，反应性充血比单独施加压力时更大。分享力比压力更有效。如果压力较小，则不受份额力的影响。在这些结果中，份额力与压疮有很强的关系，注意份额力对预防压疮很重要。

It is said that pressure ulcers is caused by not only the pressure to but also the share force to human body. In this research, we developed a mechanical system which has the mechanism to give the pressure and the share force to the sacral part of human body. This mechanism has two motors to give two forces and three load cell sensors to measure forces. Therefore, this system can control the value of the pressure and the share force using load cell data and motors, it is possible to give a certain controlled load to human body. And also, this system can measure the blood flow using Laser Doppler flow meter at the part of the force loaded.Using this system, we did experiments to measure the blood flow when we gave certain forces. We give the pressure forces 6kPa,10kPa,14kPa and these pressure forces plus the share force 4.5N. We evaluated the damage of each condition by the reactive hyperemia using the data of the blood flow. We got following results though these experiments and analysis.1.The reactive hyperemia is bigger according to the pressure force value, the damage to the human body is coming bigger.2.When we give both pressure and share forces, the reactive hyperemia is bigger than the only pressure3.The share force is more effective than the pressure.4.There is no influence of the share force if the pressure is small value.In these results, the share force has strong relation to pressure ulcers and it is important to pay attention to the share force to prevent pressure ulcers.