Filament monitor for FlashForge printers

[toybuilder]

Besides the cost of this thing and it's limited capabilities, that right there is a serious deal breaker.

At the current cost, I would want these functions added:
1) This reset chore to be automated by the printers control board.
2) I would also want a filament width measurement system.
3) A way to notify (text or e-mail) me when a failure is detected.

#1 depends on the printer to signal a start of a new job to the monitor. The monitor itself could support this feature. In fact, one could wire already wire a signal line to the RST pin on the expansion connector to do this.
#2 Width measurement would add complexity and cost; and would require software on the host software or firmware on the printer to do something useful with the information. I believe people at SD3D is trying to do something along those lines. On Sailfish-based firmware (FF's for example), there's no good way for dynamically compensating for filament diameter, as the x3g format specifies target positions in stepper counts.
#3 Would require additional hardware to connect to the network, which this device cannot do on its own. Your sensors.org idea could work, though.

The reason for the manual reset of the sensor is simply because there's no other way to tell the difference between an end of a print job and a failed print. So the Tunell monitor is designed to take a "start of job" signal in the form of the reset button. As I mentioned, with additional development (firmware on the Tunell monitor and the firmware or software of the device connected to the monitor), it would be possible to automate this process.