USB-6009 + GPS

[ABrooks]

Hi, I have a NI /USB-6009 which I am recording the movements between two carriages of a train whilst it negotiates the rail network. I have two x,y inclinometers and a couple of LVDTs to measure the yaw, roll & pitch movements. I am using the LE version of Signal Express. I have succeeded in collecting the required data. However, my customer has requested further measurements and would like to include a GPS reference on the data set. The idea being that if an unexpected movement occurs, the GPS reference could help to identify where on the network it occurred.  To my question; Is there a GPS sensor that will work with the USB 6009? Or is there a way to add a time to sync the data on the 6009 using Signal Express LE?  I could merge the two data sets at a later date. Things you should know! I have a limited knowledge of programming, hence the use of signal light. Any additional equipment must be portable, customer requirements or quick instalation and removal.  Thanks Andrew

[SnowMule]

The 6009 alone isn't going to do anything with GPS.

What's the 6009 plugged into?  There's cheap GPS receiver options out there, either bluetooth or serial that output NMEA strings.  Most handheld receivers have a serial connection (pic related, my 76Cx has both 9600-baud serial and USB output).  Connect the receiver to the host PC and read/parse those strings.

http://www.thegpsstore.com/Garmin-GPS-18x-USB-receiver-for-PC-Antenna-Only-P1841.aspx

http://www.amazon.com/GlobalSat-BT-368i-Bluetooth-GPS-Receiver/dp/B0018YZ836/ref=pd_sxp_f_r

[ABrooks]

Thanks for your reply Snowmule,

I've spent most of the day reading up on this, and your suggestions have come in most of the articles. The 6009 will be connected to a laptop, I need to be as portable as possible.

As far as I can work out, signal express LE will be my stumbling block. I'm not sure if it will allow me the time and date stamp the data coming from the 6009.

Excuse my ignorance, I havn't done anything like since leaving university. I'm a bit rusty! 

[SnowMule]

How precisely do you need it timed?  With an external GPSr and a 6008, the best you'll be able to do is about a second.  There may be some coding tricks and hardware cheats you can do to improve that, but I wouldn't count on less than ±1sec.

However, using GPS, that ±1sec will be worldwide...

Date/timestamping the data from the 6008 will be done in software, as the 6008 has no hardware timing functionality. 

[ABrooks]

Thanks again Snowmule!

I think that's the way I'll be going. 1 sec will be acurate enough for my purposes. 

I can convert to csv files and create a lookup to merge the data. 

Thanks again

Andrew