基于WIFI的振动信号采集仪的研究与实现
发布时间：2019-01-16 03:21
【摘要】：建筑受外力作用、机械设备运行都会产生振动信号。而这些振动信号中含有大量的结构和设备运行状态信息,通过分析这些振动信息可以很好的了解其运行状态,在其出现细微故障但不至于产生较大隐患前将故障诊断出来,可以避免故障隐患带来的较大损失。因此振动信号的采集与分析十分必要。目前有线式振动信号采集与分析仪器已经比较成熟和完善,但是对于无线传输的振动信号采集的研究还不够成熟和完善,因此本文进行了基于WIFI的振动信号采集仪的研究。本文深入分析和研究了 LwIP协议栈的基本原理与实现方法,并根据振动采集仪仪上行发送的振动信号数据量大,下行发送的指令数据量小的特点对LwIP协议栈进行了改进。通过裁剪协议栈中不必要的功能,优化协议栈阻塞窗口值的更新算法,采样数据指针的传递方式,提高了振动信号数据的发送效率。硬件设计上,本文设计了一种多类型可编程传感器接口电路,可编程设置信号接入类型,如单端电压输入、差分电压输入、ICP输入、交直流耦合。能够接入位移、ICP加速度和速度传感器等多种类型的传感器。采用24位高精度A/D,使采样具有较高幅值相对精度。采样频率和通道增益可编程控制,为增益和采样率控制提供了硬件保证。设计了 SDIO__WIFI模块接口电路,使信号可实现WIFI无线传输。软件设计上,移植了实时操作系统uC/OS-Ⅱ和改进了 LwIP协议栈。实现了基于wifi的振动数据上传和配置命令接收。同时,设计了 ARM和计算机端数据采集的通讯协议,实现了电路参数的配置和采样数据的有效传输。根据输入信号的特征,改变采集通道的增益以及A/D的采样频率,提高了信号采集精度和传输效率。通过最终测试,本文设计的振动信号采集仪可以很好的实现各项功能。能够通过指令切换不同的传感器模式,能够实现0～40kHz频率范围内的振动信号的采集,采样幅值相对精度不大于0.2%,WIFI传输距离空旷环境中可达100m。同时系统在改进LwIP协议栈后的WIFI的传输速率最大可以达到4.5Mbps、丢包率不超过0.01%,明显改善了振动数据量大时发送速率低的问题。
[Abstract]:The building is subjected to external force, mechanical equipment operation will produce vibration signal. These vibration signals contain a large amount of structure and equipment running state information. By analyzing these vibration information, we can understand the running state of the vibration signals, and diagnose the faults before there are minor faults but not big hidden dangers. Can avoid the fault hidden trouble brings about the big loss. So it is necessary to collect and analyze the vibration signal. At present, the wireline vibration signal acquisition and analysis instrument has been relatively mature and perfect, but the research of wireless transmission vibration signal acquisition is not mature and perfect. Therefore, the research of vibration signal acquisition instrument based on WIFI is carried out in this paper. In this paper, the basic principle and implementation method of LwIP protocol stack are deeply analyzed and studied, and the LwIP protocol stack is improved according to the characteristics of large amount of data of vibration signal sent up by vibration collector and small amount of instruction data sent down. By clipping unnecessary functions in the protocol stack, the algorithm of updating the blocking window value of the protocol stack is optimized, and the transfer mode of the sampling data pointer is obtained, which improves the transmission efficiency of the vibration signal data. In hardware design, a multi-type programmable sensor interface circuit is designed, which can be programmed to set the type of signal access, such as single-terminal voltage input, differential voltage input, ICP input, AC / DC coupling. Can access displacement, ICP acceleration and velocity sensors and other types of sensors. The 24 bit high precision A / D is used to make the sampling have higher amplitude relative precision. The programmable control of sampling frequency and channel gain provides hardware guarantee for gain and sampling rate control. The interface circuit of SDIO__WIFI module is designed to realize WIFI wireless transmission. In software design, the real-time operating system uC/OS- 鈪，
本文编号：2409406
[Abstract]:The building is subjected to external force, mechanical equipment operation will produce vibration signal. These vibration signals contain a large amount of structure and equipment running state information. By analyzing these vibration information, we can understand the running state of the vibration signals, and diagnose the faults before there are minor faults but not big hidden dangers. Can avoid the fault hidden trouble brings about the big loss. So it is necessary to collect and analyze the vibration signal. At present, the wireline vibration signal acquisition and analysis instrument has been relatively mature and perfect, but the research of wireless transmission vibration signal acquisition is not mature and perfect. Therefore, the research of vibration signal acquisition instrument based on WIFI is carried out in this paper. In this paper, the basic principle and implementation method of LwIP protocol stack are deeply analyzed and studied, and the LwIP protocol stack is improved according to the characteristics of large amount of data of vibration signal sent up by vibration collector and small amount of instruction data sent down. By clipping unnecessary functions in the protocol stack, the algorithm of updating the blocking window value of the protocol stack is optimized, and the transfer mode of the sampling data pointer is obtained, which improves the transmission efficiency of the vibration signal data. In hardware design, a multi-type programmable sensor interface circuit is designed, which can be programmed to set the type of signal access, such as single-terminal voltage input, differential voltage input, ICP input, AC / DC coupling. Can access displacement, ICP acceleration and velocity sensors and other types of sensors. The 24 bit high precision A / D is used to make the sampling have higher amplitude relative precision. The programmable control of sampling frequency and channel gain provides hardware guarantee for gain and sampling rate control. The interface circuit of SDIO__WIFI module is designed to realize WIFI wireless transmission. In software design, the real-time operating system uC/OS- 鈪，
本文编号：2409406
本文链接：https://www.wllwen.com/kejilunwen/zidonghuakongzhilunwen/2409406.html
