measuring velocity

[amz23]

For a school project, I am looking for a way to measure  velocity using the bnc2120 connector. What device would measure velocity and connect to the bnc2120 terminal block? THe vehicle i'm measuring the speed of is powered by a shrouded wind turbine, and can move directly in the wind. I need to measure the velocity of the vehicle and measure rpm of the blade.

[Ali M]

Hello amz23,

In order to best answer this question, I'm assuming you will be using a digital encoder to measure pulses to obtain angular velocity (in RPM) for the blade. If so, the NI BNC-2120 interfaces with our X Series, M Series, E Series, S Series, and NI 671x devices. These devices have counters e.g. to measure velocity (for example rotational speed of a shaft) you will need a signal proportional to speed, squared and in TTL/pulses standard to input to the counter. I have included a link (1) with more information on the BNC-2120 and a detailed list of the different device series mentioned above (see left pane of the page). To learn more about counters/encoders, see link 2 below of the M Series User Manual, Chapter 7 on Counters; or search "encoder" at www.ni.com for tutorials and LabVIEW examples on these measurements.

1. NI BNC-2120:  http://sine.ni.com/nips/cds/view/p/lang/en/nid/10712

2. M Series User Manual: http://digital.ni.com/manuals.nsf/websearch/2025C99AB0614F9E8625748000577B9A.

Regards,

Ali M

Applications Engineer

National Instruments

Message Edited by Ali M on 04-12-2010 05:01 PM