I have a home-built pressure calibration device -- compressor to air tank to 
some accurate pressure gauges and a sensor to be calibrated (the unknown).  
Also have a temp sensor/gauge to record the temps near the sensor.  The 
unknown sensor is connected to a PIC-based circuit that has a numeric 
display.  From 100psi, I slooooowly bleed it to zero while writing down 
simultaneous readings from all sensors.  I then calculate (spreadsheet) and 
then re-map the tables in the PIC circuit to correct the numeric values.  

Works, but takes a long time, and now I need to run this calibration process 
many times -- for a bunch of sensors, at different temps.  So I need some 
automation...

I can electrically control the compressor on/off, and get an 
electrically-actuated valve to bleed the pressure.  What I need is a software 
program that (a) has output lines to control the valves, (b) can read an LED 
display (as I suspect that modifying the application circuit to produce a 
serial or other output would/could affect the calibration of that circuit),  
(c) has a simple programming/scripting language so I can automate the 
process.

My script would them be setup to control the pressure to known values, and 
record all readings each time.  And it canl control the temp as well with a 
heater during all of this.

Does anything like this exist?  Requirement (b) would also let me read the 
accurate pressure gauges, which do not have any outputs, but I expect that 
may be the not-so-off-the-shelf part of this puzzle.  At this point, I'd be 
up for the software controlling the pressure and temps and taking photos of 
the gauges, so I can write them down later.  Yeah, seriously.

Any opinions on this or other suggestions?

Cheers,
-Neil.


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