For the second lab experience, we will examine the problem of controlling one of the systems that were characterized in the first three weeks.  You need to evaluate Proportional Control.

        In Proportional Control, the control effort is proportional to the error in the system.  You need to ensure that your system is a proportional control system as much as possible.

        Each system has had the its dynamic characteristics formulated and measured.  Lab reports will be available to you as soon as possible.  Your instructor will make reports on these systems available electronically when they are available.

        You will need to evaluate how well your control design performs.  Be sure that you understand your goal here.  It may not be possible to produce a super control system for the system you choose.  You need to evaluate how well it is possible to control the system using only proportional control.

There are several aspects of performance that can be considered and measured.  They are listed next.

ACCURACY - How closely does the system come to producing the user-specified values?)  You will need to pay attention to Steady State Error (SSE) for standard inputs like steps.

SPEED OF RESPONSE - (Quicker is better!)  You will need to learn a little about standard measures of speed of response like rise time.

RELATIVE STABILITY (e.g. %OVERSHOOT) A small amount of overshoot is not undesirable, but too much overshoot should be avoided.  You would also not want high frequency oscillations in the system.

SENSITIVITY TO PARAMETER CHANGES IN THE CONTROLLED SYSTEM  Any system changes in time and is subject to external disturbances.  As appropriate you need to consider how your control system handles these problems.

        The above four measures of system performance are standard measures you can use to specify how well your system performs.

UNANTICIPATED PROBLEMS  In any system you may discover that there is some sort of problem to be solved - a problem that is not obvious even though you may have nice dynamic descriptions for the systems.  If time permits you should solve the problem.  If you run out of time, you must at least be able to formulate what the problem is for your system.

        As much as possible you will need to relate the theory we develop in the classroom to what happens in lab.  I will grade these reports looking at the following aspects.

How well did you evaluate proportional control for the system you had, with a focus on the performance measures listed above?

How well did you integrate theoretical predictions of behavior into your work?

Reference(s)

• A Link to Filtering Pulse Signals