I've been thinking hard about how to implement a temperature controller, and I've come up with an initial plan.

I'll plan on using the PSSR/ZC tail to control the heating level.

First, I'll train a neural network to understand the relationship between power level and temperature so that given a temperature set-point as input, the network will output the appropriate power level to use.

Second, I'll determine, experimentally, the maximum time it takes for the temperature to stop increasing after cutting power. Let's call this time (MT)

To reach a certain temperature set-point, I'll apply full power and continually estimate the remaining time until the set-point is reached (RT). When RT - MT reaches zero, I'll cut power and monitor the rate of change in temperature. One the slope of the rate of change of temperature reaches some number (0.5?) I'll set the power level to the appropriate amount for the goal temperature. This should cause the temperature gain rate to level off more slowly, and reach zero when it gets to the goal temperature.

It's a plan... having gone through some literature on working with temperature controllers in systems with delay, I've come to the conclusion that the problem of control, regardless of implementation, is extremely complex. For now, I'd like to get something working, even if it isn't perfect.