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

据说，压疮不仅是由对人体的压力引起的，也是由对人体的分担力引起的。在这项研究中，我们开发了一种机械系统，它具有对人体骶部施加压力和分力的机制。这种机构有两个马达来提供两个力，三个测力传感器来测量力。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分力的大小，从而有可能给人体施加一定的受控载荷。此外，该系统还可以在受力部位使用激光多普勒血流计测量血流量，并利用该系统对施加一定力时的血流量进行了测量实验。我们给出了6kPa10kPa14kPa3种压力值和这些压力值加上4.5N分担力。利用血流量数据评价各状态下反应性充血的损害程度。通过这些实验和分析，我们得到了以下结果：1.压力值越大，对人体的损伤越大；2.当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；3.分担力比压力更有效。4.当压力较小时，分担力没有影响。在这些结果中，分担力与压疮有很大的关系，注意分担力对预防压疮有重要意义。

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.