Abstract : the paper introduces the controlling system of virtual instruments for the model of cotton grabbing machine and discusses mainly the hardware connecting and software of the controlling system of virtual instruments . the result of the system indicates that more applying systems can be developed in the construction of laboratories with the help of virtual instruments 文摘:介绍了抓棉机模型虚拟仪器的控制系统,着重讨论了虚拟仪器硬件连接和软件程序;该套系统的成功运行结果显示,在实验室建设中运用虚拟仪器还可开发出更多的应用系统。