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Fire Detector 2

So I set up the Chipkit Uno32 with the temperature sensor TMP36 from, installed the serial port monitor on the laser pc and tested the system. All fine so far.

The data collected was pretty good as well.

The left shows room temp with the slight increase being the heat detected from my hand on the outside of case. The peak is where I took a very technical approach and waved a lighter under the sensor!

Unfortunately as soon as I turned the laser on it all went wrong! The data became massively noisy as you can see here:

The flat bit in the middle is where I turned the laser off. 

The laser is not running, just sitting in ‘standby’. The only thing running is its controller and the steppers in a fixed position.

First thing I did was swap the USB port to a different PC, just in case, but no improvement. I also ensured that the Uno32 was not shorting on the body of the laser.

Next I turned off the laser but left all the cooling and extraction on, this gave good data!

So in summary, the laser is interfering with Uno32 / temp sensor despite them being isolated from each other. Great. I will try increased insulation and moving the Uno32 off the machine somewhere.

If anyone has any suggestions (or something really obvious I have missed) please let me know!

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Fire Detector

After Martins fire, and have a near miss myself I am planning to build a fire detection system for my laser. I am already building an Axolotl temperature sensor system (which I am logging at the moment) so when that is complete I will have a look at using a similar system for fire detection. Whilst the temp sensor is being finished I am going to log the temperature in the laser to see what sort of range I am dealing with. For this I am going to use the chipkit / arduino prototype for the Axolotl system and write something simple to monitor the com port on the PC.

I will strip the LED and buzzer off and hook up the temp sensor directly.

More details and code will be published when I have it hooked up.