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It looks like you must add dead time to the 4 time constants. You could plug that equation into wxMaxima and used the ilt() function

Early PLCs didn't use RTOS. Now they are necessary to handle things like communications and timed events. If you really want you can probably get by without an RTOS but as you add features you will find the RTOS simplifies things. Often you don't need a full blown RTOS but just a real time...

There is too much misinformation here. For the best performance the inner loop should have a faster response time than the outer loop. However, it isn't necessary if you are willing to put up with sub optimal control. If the open loop transfer function of what is being controlled is known then...

"I think this education system is a mistake. " Yes, I agree. You are not prepared for this. On top of that, neither are the professors that teach control theory since many or most of them have never controlled anything. They only teach what they have been taught by others that teach only what...

Since each valve can supply 100% of the required flow then I would just use one valve at a time. What is the fluid? The pressure will change a function of the net flow in or out. dPressure/dTime = BulkModulusOfFluid*(FlowIn(t)-FlowOut(t))/VolumeOfFluidUnderPressure Control will be easier if you...

Where do the values for m and b come from? The problem I have with most control books and professors is they have no idea what reality is like. In real life you aren't given a transfer function. In 35+ years of control I have never seen a system with a documented transfer function. The values...

Last week ctoren was trying to control room temperature with a fan and using feed forwards. Now it is cruise control. What happened to the dead time? How was it determined that m=980 and b=40? This looks like a problem out of a book but he is trying to figure out how things change as the...

You are bowing to the SJWs

Oh no! PC has struck again! So if I am sitting a restaurant, I am the client and the person bringing me food is the server. I wonder if restaurant servers will be offended now.

It looks like ctoren is trying to find the dead time for a transfer function. There is no equal sign in this case. Dead times are determined empirically.

You basically repeated your first post and have provided no new information. I am crusty old EE and don't like to play 20 questions but I will be be nice. 1. does the fan blow cool air or hot air? Are you trying to heat or cool the room? 2. Can you measure the room temperature? 3. What is the...

Feed forward control would be proportional to what? I motion control a the velocity feed forward output is proportional to the target speed and the acceleration feed forward is proportional to the target acceleration. In a temperature heater control the feed forward would be proportional to...

This is not a PID problem. It is a target generator or motion profile generator problem. The calculations are too difficult to do by hand or calculator. A computer is necessary and software that can do symbolic math. Basically it involves solving a system of N equations for N unknowns. N is...

Yes! The problem is that you are not using the right form of PID. You need to use the incremental form of PID where the P and D term are computed by multiply the gains by the differences in the process value and then integrated. The integrator will not wind up when a step change in...