Please help me finish this program

[twobig86]

Hi I am currently trying to finish this project with labview...though I have run into some problems.  First off here is the explaination of the project.

And lastly, the project, a bicycle dash-o-meter, which will return us to using LabVIEW to produce a program which will take the rotations of a wheel (27" diameter, with a sensor mounted at 6" from the center), and calculate distance, speed, time, ...).  We'll use a simulated input of course, but we could interface it to a real bicycle wheel or any wheel or shaft for that matter.

My problem is that we have only been using labview for 2 weeks and it is now due tomorrow.  I have a program all drawn up but its not controlled by a blinking led...how to I get a simulated signal to run this.  Also how do I get the distance to increase without just changing...for example if I went at 100 km/h for 16 minutes thats roughly 16 km how to I get it to keep that 16 km and then slow down the speed to 50 km/h and get the 16km and hour to increase at the new rate?

I hope some of that made sense.  Any help is appriciated. 

Here is what I have...P.S. Labview 7.0 is what we have here at the school.

[LabViewGuruWannabe]

Two weeks is hardly enough time to really understand most of what LabVIEW can do for you. Also, I hesitate to give anyone answers to their school projects.

That being said, there is probably an example or 3 that might help you. Take a look at some of the Fundamentals examples, or in the Help Contents under Fundamentals, especially Building the Block Diagram.

B-)

Sorry, I didn't see your vi at first. I'll look at it and see if I can help any...


Message Edited by LabViewGuruWannabe on 12-13-2007 02:50 PM

Message Edited by LabViewGuruWannabe on 12-13-2007 02:52 PM

[thisisnotadream]

I agree with the "no answers" rule...as well as the "2 weeks is not enough time".  I would like to give you a hint of where to focus your efforts for you second issue.  I think that a feature known in LabVIEW as a "shift register" would come in very handy in your while loop calculating total distance travelled.

Dan

[LabViewGuruWannabe]

Dan's suggestion is really good.

For your LED to blink, determine logically when you want that to occur.

One way is to change the state of an LED at each revolution, kind of like a switch. At the start, the LED is OFF. When the distance traveled is greater than the circumference, the LED comes ON, and your distance counter is reset to zero. When the distance traveled is again greater than the circum., change the LED again.

Another way is that when the wheel rotates one revolution, turn the LED ON for a set time, like 0.5 seconds. However, at speeds greater than 120RPM, the LED will always be ON.

What you are really doing is counting pulses from the sensor, and the time between them.

If I might make a couple of suggestions for your code, don't hide the STOP button. Also, try to always keep your wiring to flow in a Left-to-Right direction. That will certainly help with understanding what everything does, and will make troubleshooting a great deal easier.

B-)