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QUOTE (Neville D @ Apr 7 2008, 06:21 PM) Thank you for your good reply. I realize that I didnt describe my problem good enough, sorry for that. I would like to use two cameras for monitoring of a robotized laser welding cell. The distance is about 3-4 meters and I want the picture in colour, with good resolution at a pace of ~25 frames/second. I have worked with Basler cameras before and find them good enough for my purpose. The problem is that I'm not very good at lenses - I need to look into this more. Could you recommend some good readings about lenses? Thanks in advance. /Mattias

QUOTE (Neville D @ Mar 13 2008, 01:16 AM) Hi! What FW-cameras do you recommend that are cheap? I have been having the same problems and I am thinking about switching to firewire instead of USB. Regards Mattias

Hi! I have just bought a license of Labview with the vision toolkits. Have anyone of you experts tried a Pinnacle Movieboard (PCI) together with the vision toolkit in Labview? I would like to capture frames (20 frames/second) from the board into a simple movie in this first setup - later one, would I also like to do some image processing. But the first question is: Is it even possible to use the board, or should I go for a NI-board instead? Regards Mattias

I have now also added a procedure to my database called AddData. I have managed to decrease my write time to about 33 ms by using this procedure instead of having a "insert into... etc" . I have also added the possibility to save data to a simple text file. I'm having no problems at all when using this method, the write time is as low as 1ms or less. But when saving to the database the disc activity increases very much compared to when only writing to the text file. Do you know why the disc activity increases when using the database instead of a simple text file? I have measure my drive by using HD Tune and I see no problems with the disc performance. Thanks in advance for any advice! Regards, Mattias

Queueing will unfortunatly not solve my problems since the queue is groving faster then the "write-to-db-vi" - and I'll write data for hours in my case. I've now tested a lot of things and finally made a new VI consisting of only... - Open DB - Write one int and one string of seven letters - Close DB ...the time it taks for writing data to the table is still 40-60ms. So, I now wonder, is this a normal case for you too? I mean, can one say that saving data to a MySQL-table over ODBC will take about 50ms in general? Thanks for your time. Regards, Mattias

First of all, thank you very much for your time. All of you have been really good support to me. I have now added the front panel and block diagram for my test-VI. I have implemented the queue system and separate loops for producer and consumer. However, since the queue is building up faster then the consumer loop consumes values, the queue is building up quite fast and the disc starts working. The test database table that I add data to is created by a simple: create table test(aa int, bb char(15)); ...I'm sure that this can be improved in some way. I always open and close the connection to the database "outside the loop". However, it still takes some 40-50 ms to save the data to the database table - so, unfortunatly no progress to far. I currently just want to save the data. Any more advise will be gratefully accepted. Regards, Mattias

Hi! I have built a VI to aquire and save measurement data to a MySQL database. The data contains of 60 "ints and floats" and they are saved using the DB Tool Insert Data.VI. There is no problem with the functionality....except for the speed. When I enable the saving to database my software loop time increase from 8ms to ~50ms. When I turn off the saving the loop time decrease to 8ms again. The CPU power meter never goes above 15% of maximal use. The MySQL and LabVIEW-program runs on the same computer. I have LabVIEW 8.2.1 and Database Connectivity Toolbox. So, I have a couple of questions. 1. Do you think I have over estimated the possibility of using LabVIEW and MySQL for this type of application? (60 ints/float @ 100 Hz) 2. Do you have any tip for increasing the performance of my SQL Insert statement? I will run the control system for several hours so it will be quite a lot of data in the end. Thats why I would like to use a database. The database will also give me other great advantages compared to writing to a "text-file", ie search and extract data from other computers during runtime. I'm quite new to this type of application so any advice will be gratefully accepted. Best regards, Mattias Ottosson