心肺功能评估训练系统的恒功率控制

Constant power control in cardiopulmonary function evaluation and training system

针对在心肺功能评估和训练中由于蹬踏速率波动导致运动负荷(功率)无法维持恒定的问题,设计了一种新型磁阻发生装置,可实时、快速、精确地调节阻力,并通过模糊PID控制实现了一定范围内不受蹬踏速率影响的恒功率控制。为验证恒功率控制效果,在改进后的心肺功能评估训练系统和Monark心肺功能评估训练系统上分别进行了恒功率实验,测试结果表明:对于改进后的系统,蹬踏速率在50~70r/min变化时,实时功率曲线控制在目标功率曲线±8W内上下波动,2min内整体平均功率与目标功率误差小于2 W,系统克服了由于蹬踏速率改变而导致人体输出功率无法恒定的问题;相比Monark系统,在相同目标功率及相同蹬踏速率变化条件下,改进后的系统在恒功率控制精度上整体提升了2 W,同时降低了控制误差。

For the non-constant exercise workload（power）due to the fluctuation of pedaling rate in cardiopulmonary function and training system,a new magnetic-resistance generator was designed to adjust the resistance real-timely,instantly and precisely.The constant power can be maintained independent of the pedaling rate within certain range by applying fuzzy PID control theory.To validate the effect of constant power control,experiments were carried out on the improved cardiopulmonary function evaluation and training system and on the Monark cardiopulmonary function evaluation and training system,respectively.Results show that,for the improved system,the instant power curve fluctuates within 8 W of the target power curve,and the control error between the average power during two minutes of the test and the target power is less than 2 W as the pedalingrate changes in the range of 50 r/min to 70 r/min.The new system overcomes the influence of nonconstant power output due to the fluctuation of pedaling rate.Compared with the Monark system,the new system improves the constant power control accuracy by 2 Wand reduces the control error under the same target power and the same change of pedaling rate.