【摘要】 目的为了解决呼吸运动对放疗的影响,需要对呼吸时肿瘤位置和体积的变化进行详细的研究,以便精确地确定个体化内靶体积,由此需要研制可以对肿瘤形变进行模拟运动的仿真平台。方法设计利用STC89C52RC单片机提供控制信号,结合驱动芯片ULN2003对四相步进电机28BYJ-48(12VDC)进行驱动,从而带动皮带进行微小的往复运动。在皮带之上固定承载骨骼用的玻璃板,玻璃板和骨骼的重量再由安装在玻璃板下方的带有轴承的支架承担,从而巧妙地实现了呼吸运动仿真平台的设计。结果经过多次测试证明所设计的呼吸运动仿真平台性能稳定可靠,完全满足对仿真的需求,甚至可以在超出当初设计时载重要求两倍的情况下进行超负荷运转。结论该单片机控制步进电机系统具有快速启动和停止的特点,其驱动速度和指令脉冲能严格同步,具有较高的重复定位精度,并能实现正反转和平滑速度调节,从而可以较好地实现需要的肿瘤模拟运动规律。更多还原

【Abstract】 Objective In order to solve the problem of breathing movement affecting the accurate radiation, we must carry out detailed studies about the position and volume of tumor during breathing. So a breathing movement simulation platform is necessary to develop in helping us make it come into being. Methods We used single chip to provide control signals, ULN2003 to drive stepping motor 28BYJ-48 (12 VDC) and stepping motor to carry the belt which had a glass fixed on. The bones were put on the glass with a support under it to take up the weight of glass and bones. All these measures ensured the success of breathing movement simulation platform. Results Several times of tests proved that the breathing movement simulation platform had a stable and reliable performance which could fully satisfy the need of simulation. It could even work well under twice weight of the load bearing. Conclusions The single chip system with stepping motor has the characteristic of quick start and stop. The driving speed can strictly keep pace with command pulse. It has a higher accuracy of repeating position as well as positive and negative rotation with smoothly controlled speed to simulate tumor movement.更多还原