digital speedometer

[navveed]

hi!

please help me. is there any one who could possibly send me a programme in either C language or assembly to programme PIC so that pulses in a specific time period after being counted by a counter are converted into a unit of speed that is either KM/h or miles/h.

Well the summary is somewhat like this, magnetic sensors to be used passing the pulses picked up from a rotating wheel and passing it to the counter and then finally to the display that is a seven segment display. In words it seems simple but I am confused in last part that is the display part. I have figured out what type of sensor to use, what type of counter to use and but the display will only show the number of pulses coming in but not the speed so is there any way that the pulses after being counted be converted in to a unit of speed either km/h or miles/h. well some one send me the following information if it could be a help to you;

So if you have one pulse per rotation of the wheel, then the distance travelled per pulse is the circumference of the wheel.

So if you have 10 pulses per second, the speed is 10xcircumference per second, multiply by 3600 to convert to hours, and divide by the ratio of the circumference to miles (or kms) to give the speed as kph or mph.

so if its possible can anyone send me the programme to programme pick to do the job that is simply convert pulses into a unit of speed.

your help will be appriciated for ever

thanks

 

[eblc1388]

I don't understand why you would need to ask.

One can simply multiply the number of pulses per second by a constant to obtain the value of mph.

The constant K is equal to 60x60x(wheel circumference expressed in mile).

So in C language, its just mph = K * pps, where pps = pulses per second.

Did I missed something?

On second thought, I reckon you only have the pulses to work with and do not yet have the "pulses per second" value. You can therefore measure the period between each pulse and work out the pulses per second value. The pulses per second value is the inverse of the time between each pulse.

 

[motion]

This should have been posted as a continuation of an earlier thread he started.

https://www.electro-tech-online.com/threads/dot-matrix-moving-sign.18966/