Alex
The PID Control Toolkit has the implementation of the PID algorithms and the Fuzzy Logic Toolkit. It has some auto-tuning algorithm to help tune the parameters, however, it does not help to design the parameters that should be used for the PID.
The Control Design Toolkit is a collection of functions that, based on a linear model obtained by calculation, experiment or simulation, you can calculate the parameters to be used for a controller. In other words, it allow to create a more complex controller to a system, other than PID.
Both product complement each other since you could start identifying a system, design a PID controller with Control Design toolkit and implement the controller with the PID Toolkit.
Let me know if you need more explanation on this subject... Hope this helps!
Barp - Control, Simulation, RTT and HIL - National Instruments
