Demonstration of the Source of Motor Program Signal: Study on the Correlation between Muscle Strength and sEMG Signal in Normal Children and Adults

To investigate the relationship between muscle strength and sEMG of biceps brachii during elbow flexion by measuring the maximum muscle strength and sEMG value of normal children and adults, and to analyze their sources, so as to lay a theoretical foundation for the method of motor program reconstruction to restore the function after brain injury, 30 healthy children aged 9 - 10 years and 30 adults aged 20 - 30 years were randomly selected. The muscle strength and sEMG of biceps brachii during elbow flexion were detected and recorded, and the data were statistically analyzed. The muscle strength of children was significantly lower than that of adults (P < 0.001), and the sEMG value of biceps brachii was significantly lower than that of adults (P < 0.001), but the sEMG value per kilogram force of children was significantly higher than that of adults (P < 0.01). The results show that there was a very significant difference in pull (efficiency) between adults and children when there was no significant difference in SEMG signal intensity. This is because although children’s central nervous system has matured, the muscle tissue has not been well trained, resulting in insufficient muscle strength. The muscle strength of adults is significantly higher than that of children, because they have been exercising for a long time after the development of the central nervous system. It is proved that sEMG signal is not produced by muscle contraction itself, but comes from the motor program signal of central nervous system which drives muscle contraction, and it is produced before muscle contraction.

基于DSP+CPLD的车用开关磁阻电机驱动控制系统的设计

介绍了电动汽车动力源,开关磁阻电机驱动控制系统。提出驱动控制系统采用DSP+CPLD为主控制器的设计方案,详细分析了硬件电路和软件流程。该系统满足汽车行驶要求,能够实现平稳起动、连续变速、制动和倒车等功能。系统快速稳定、结构简单可靠,在电动汽车上有广阔的应用前景。

无刷直流电机DSP逻辑控制程序的Petri网设计方法

提出一种无刷直流(BLDC)电机数字信号处理(DSP)逻辑控制程序的Petri网设计方法.首先,建立霍尔传感器和电机旋转方向的Petri网模型;其次,利用功率管(MOSFET)二二切换规则,设计功率管通断的变迁,获得电机的逻辑控制Petri网模型,并根据Petri网可达图算法,计算无刷直流电机动态系统的状态集合,并利用换相逻辑逐个验证;最后,借助Petri网变迁的激发规则,设计无刷直流电机DSP逻辑控制程序,并对文中方法进行实验验证.结果表明:文中方法能够保证控制程序的正确性和可靠性,可以有效地简化无刷直流电机DSP逻辑控制程序的调试过程.

基于矢量控制的PMSM高性能伺服系统设计

在TMS320F2812 DSP硬件平台上,采用C语言Q格式编程技术,实现了基于矢量控制和空间矢量脉宽调制(Space Vector Pulse Width Modulation,简称SVPWM)技术的永磁交流同步电机(Permanent Magnet Synchronous Motor,简称PMSM)双环速度控制或三环位置控制,通过串行接口设置系统4种工作方式中的一种。由实验结果可以看出,系统具有良好的动态响应特性,可广泛应用于数控系统、自动生产线等需要高精度伺服控制的场合。

用虚拟仪器实现步进电机任意波形转速的控制

详细地阐述了利用LabVIEW图形编程语言进行虚拟仪器开发,并设计了一种软信号发生器。在此基础上,构建了基于NI虚拟仪器的控制系统。用信号发生器所产生的各种不同的波形信号作为步进电机的输入信号,再结合NI公司的硬件设备,进行步进电机任意波形转速的控制实验。实验表明,这种控制系统具有控制灵活,操作方便的特点,将虚拟仪器用于步进电机任意波形转速控制的研究是可行的。