nongdy

HI, I installed DIAdem 10.0 in one PC, after all the installation, when I started the diadem program, it poped up a dialog box, "the internal diadem data organization returned an initialization error." when I choosed "OK", the diadem program shuted down. it was very strange. I uninstalled all the LabVIEW software and cleaned up the value about "diadem" and "labview" in the registry. then installed all the software again, the problem is still the same. the labview8.0 software works properly. only diadem10.0 had problem. the operating system of the PC is window XP professional edition. CPU P4 1.8G, HD 40G, RAM 256 MB DDR266. chipset 845G what is the problem? what should I do? Regards, Nongdy

May you tell me what is the function that I indicated in the drawing of attachment? I tried to replicate your integration vi, but I couldn't find this array funtion in my LabVIEW. I am sorry. I used the professional edition LabVIEW 8.0. Thank you very much! Regards, Nongdy

yes, I have to do a lot of things for it. hehe... , thank you for your suggestion. these idea are really very important for me. it give me a lot of hints. LAVA has a very good ambience to learn labVIEW . Nice to meet everybody in LAVA. Regards, Nongdy

Thanks a lot. I would try this method to process the experiment data. May you post the Vi to me? I really appreciated it. Regards, Nongdy I forgot to say, the real vibration amplitude only 0.4~1.6mm. It is very little. so the more precise method is the better. I want to get the whole displacement history during the experiment. so the efficiency is also a problem. the first experiment was done with measuring sine vibration, the sample period is 0.0001s. but may be we also try to use the system to measure other cycle vibration signal. the vibration amplitude is about 0.4~2mm. to abtain a so precise measurement value, so difficult. I haven't too much idea now. Thank you for your suggestion. It makes me understand the integration better. Regards, Nongdy I am sorry. the whole VI could not work properly. you could see the Integration.vi used for this system in the attachments. I am trying to fix the problem about the integration related problem. Thank you very much! Regards, Nongdy Download File:post-7362-1167861211.vi

- Sensor (type, frequency range, sensitivity) (It is the PCB 3703G3FD3G accelerometer sensor. http://www.pcb.com/contentstore/docs/PCB_C.../3703G3FD3G.pdf - amplifier ( sorry, I don't know it. I will check it.　The experiment was done by other people, the system could acquire the data, but the post processing has some problem. ) - hardware filter (we don't use hardware filter, I recommend to use a low pass anti－aliasing filter. But

Thank you very much! I will try to use your suggestion tomorrow! about the sensors, those are PCB 3703G3FD3G accelerometer. http://www.pcb.com/contentstore/docs/PCB_C.../3703G3FD3G.pdf

Firstly, Thanks to crelf and torekp, My labVIEW 8.0 is the professional edition. Now, I know how to integrate the acceleration. Thanks a lot to you all. But I had the new question about the acceleration signal offset and the digital filter configuration. I need to design a digital filter (band-pass) to remove DC offset and upper useless frequencies. I got some suggestion that I need to get the minimum and maximum acceleration, and use them to determine upper and lower cut-off frequencies. But I don't know how to get them? And after I get the minimum and maximum acceleration, how to determine upper and lower cut-off frequencies of the band-pass filter. Normally, which type of the digital filter that I should choose to offset the acceleration signal and removes the high frequency noise? Normally, how do you deal with the DC offset of the acceleration signal? And how do you design a digital filter? And for the acceleration signal, in the vertical direction, there is a 1g gravity always present, how do I deal with this problem? Has anybody the experiences about these? This is the first time that I use the NI labVIEW and process the acceleration signal of tri-axis accelerometer. I hope I could get help from you. Thank you very much in advance! Regards,

Hi, I used labview 8.0 to acquire the acceleration signal from tri-axial accelerometer, and tried to filter the noise in it, and then transfer the signal into velocity and displacement of the movement by integral. The main vibration is the sine waveform movement, frequency are below 10Hz. It is something about the signal post processing, because the data acquiring vi had worked properly. (It was done by another people.) But we could not get the sine waveform of displacement output. How could I do it? Does somebody give me the general idea or some example VI? Thanks in advance! Regards,