This could be long, so apologies in advance...
I would like some pointers/advice/etc with regards to a project.
I need some form of 'black box' device that is positioned between a PC & an engine testing machine. The black box would measure 1 Digital & 2 Analogue mesaurements from the machine. During the time the machine is being measured (up to a max of 5 mintues), the measurements are passed to the PC at a slow rate, say twice per second - these are used to update the display on the PC. When the machine has stopped, the entire measurements in detail are then downloaded to the PC from the device's memory. The device is then reset and ready to go again.
The digital input measured the speed of a metal drum from 0 to 5000 RPM in an all weather, possible dirty, environment. Because of this, I was planning to use a hall effect sensor instead of some other method.
One analogue measurement measures the RPM of an engine up to a max of 20,000 RPM using an inductive pickup placed over the lead to the spark plug of the engine. I do not know how to get an Analogue 'spike' reading read into a device? An ADC?
One analogue measurement reads gas content of exhaust fumes, as a reading from about .25 of a volt to 2.5 volts. Again, how would you read this in, an ADC?
This is what I was thinking...
Measuring the time between the hall effect pulses would give you the RPM of the drum. Measuring the time between the engine RPM pulses would give you the RPM of the engine. I want the value of the voltage from the gas analyser.
All three readings need to be syncronised to each other somehow, (maybe with a running clock that is reset at the start of each test run?). This 'clock' reading could be saved against each measurement, thus giving each measurement a fixed point of time reference compared to the other readings.
The true value is when you can say that at 12,000 Engine rpm, the drum was turning at exactly 3,450rpm & the gas analyser was showing 1.25 volts.
Now - this may all be too complex to do with some form of PIC chip - but there is no harm in asking! :roll:
Getting fast readings, (such as 1000 readings / second), would be very welcome, as this gives good accuracy when the engine is accellerated hard & the readings change very quickly.
These readings are all currently read off manually & is frankly a pain in the backside, (& accuracy must be affected!). Capturing the data automatically would speed the process up ten fold, but we do not have the money for custom made automated testing machines.
My thanks for any advice in advance,
Regards
Paul
I would like some pointers/advice/etc with regards to a project.
I need some form of 'black box' device that is positioned between a PC & an engine testing machine. The black box would measure 1 Digital & 2 Analogue mesaurements from the machine. During the time the machine is being measured (up to a max of 5 mintues), the measurements are passed to the PC at a slow rate, say twice per second - these are used to update the display on the PC. When the machine has stopped, the entire measurements in detail are then downloaded to the PC from the device's memory. The device is then reset and ready to go again.
The digital input measured the speed of a metal drum from 0 to 5000 RPM in an all weather, possible dirty, environment. Because of this, I was planning to use a hall effect sensor instead of some other method.
One analogue measurement measures the RPM of an engine up to a max of 20,000 RPM using an inductive pickup placed over the lead to the spark plug of the engine. I do not know how to get an Analogue 'spike' reading read into a device? An ADC?
One analogue measurement reads gas content of exhaust fumes, as a reading from about .25 of a volt to 2.5 volts. Again, how would you read this in, an ADC?
This is what I was thinking...
Measuring the time between the hall effect pulses would give you the RPM of the drum. Measuring the time between the engine RPM pulses would give you the RPM of the engine. I want the value of the voltage from the gas analyser.
All three readings need to be syncronised to each other somehow, (maybe with a running clock that is reset at the start of each test run?). This 'clock' reading could be saved against each measurement, thus giving each measurement a fixed point of time reference compared to the other readings.
The true value is when you can say that at 12,000 Engine rpm, the drum was turning at exactly 3,450rpm & the gas analyser was showing 1.25 volts.
Now - this may all be too complex to do with some form of PIC chip - but there is no harm in asking! :roll:
Getting fast readings, (such as 1000 readings / second), would be very welcome, as this gives good accuracy when the engine is accellerated hard & the readings change very quickly.
These readings are all currently read off manually & is frankly a pain in the backside, (& accuracy must be affected!). Capturing the data automatically would speed the process up ten fold, but we do not have the money for custom made automated testing machines.
My thanks for any advice in advance,
Regards
Paul