1. Double-tank Process Hybrid Controller: Time-optimal controller –achieve fast step-change response and is used when states are far away from the reference point PID controller– get the wanted steady-state behaviour and is used when the states come close to reference point

2. execution time may change abruptly between different control modes Multiple hybrid controllers are executed by the same processor

3. Feedback Scheduling High CPU utilization avoid overload distribute computing resource evenly

4. IDEAR 1 The control method is to let the utilization to follow the given CPU utilization Usp. Take the performance error of the double-tank process system as a factor to give the control input.

5. IDEAR 2 Implement the multiple double-tank systems in true time simulator. Build two layer closed control loop. Inner one is to obtain the given CPU utilization by tuning sampling period of each tasks. The one in the outside is to obtain the trade of between the performance of control systems. To see whether the tuning of sampling time can be used in NCM model