Development of training machine with mechanical impedance display for strength training

对于力量训练机，特别是高速和高功率的机器，有必要具有安全机构。我们开发了电流变离合器的力量机。本机具有高速、大功率、高精度、安全等特点。即使本机器失控，通过使用ER离合器输入扭矩电机的速度控制，操作杆臂的旋转速度也仅为0.52[rad/s]。并通过等速载荷（0.52，4.19，8.72 [rad/s]）的实验验证了该机器的性能。实验结果表明，该机器能在± 5%的角速度范围内显示载荷。该机器在0.52[rad/s]运动时最大输出44.4[Nm]。我们提出了一个新的指标，用三维图形上的三个平面模式（角速度-扭矩平面、角-扭矩平面和角-角速度平面）计算肌肉输出的横截面和体积。肌肉力量的评价通常采用峰值力矩，而肌肉输出的特性通常采用二维曲线评价，如力-速度曲线、力-功率曲线等。然而，即使受试者之间的肌肉输出在力-速度曲线上显示出相似的实验结果，但在某些情况下，它们在包括角度数据在内的三维表面上显示出不同的特征。为了评价肌肉特性，三维指标包括角度、速度和力矩值，反映了肌肉特性的细节特性。从所获得的数据，我们组成的三维表面的角位置，角速度和扭矩数据和计算的体积由三个平面图案。利用这些指标对不同运动项目的肌肉输出进行比较。结果表明，这些指标在运动项目间存在显著差异。

It is necessary for strength training machines, especially high speed and high power machines, to have safety mechanisms. We have developed the strength machine with ER clutch. This machine could move with high speed, high power, high accuracy and safety. Even if this machine is out of control, operated lever arm rotates only up to 0.52[rad/s] by using speed control of the input torque motor to ER clutch. And we verified the performance of our machine with the experiment of isokinetic load (0.52, 4.19, 8.72 [rad/s]). As the results of the experiment, this machine could display loads within every desired angular velocity ±5%. And this machine performed 44.4[Nm] at maximum during 0.52[rad/s] movement.And we have proposed a new index for the characteristics of muscular outputs with cross section and volumes calculated by the three plane patterns (angular velocity-torque plane, angle-torque plane, and angle-angular velocity plane) on the three-dimensional figures. A peak torque was generally used to evaluate muscular strength and the evaluation with two-dimensional curve, such as force-velocity curve and force-power curve were utilized to evaluate the characteristics of muscular outputs as usual. However, even though muscular outputs among the subjects show similar experimental results on force-velocity curve, there are some cases where they show different characteristics on three-dimensional surface including angular data. In order to evaluate muscular characteristics, three-dimensional index including angle, velocity and torque value shows the detail property of muscular characteristics. From obtained data we consisted of three-dimensional surface with angular position, angular velocity and torque data and calculated the volumes by three plane patterns. By using these indexes, we compared with the muscular outputs among different types of athletic events. As a result, these indexes showed significant differences among the athletic events.