Lab 3 - Control of a Flexible Servo

The lab will be carried out remotely and you will preform all experiments at home on your own time. You perform the lab simply by reading the manual, available here Lab 3 Manual, and solving the assignments in it. (The manual is only available in English, but the Swedish translations of technical terms can be found in this control dictionary.)

To pass the lab you will need to pass two quizzes and a verbal examination discussing the findings (more information below). We encourage you to discuss and work with other students on the assignments. However, note that the quizzes should be done individually. You are of course also welcome to ask questions and discuss the lab with us at the exercise sessions.

Note, normally we run the lab on a real process so the manual may contain instructions for how to handle this process (login, start, restarts etc.). To run the lab on your own, you ignore all these instructions and instead run a Matlab simulation of the process on your own computer, see below for instructions. Also, the manual may contain references to parts of the real process that are not present in the simulated process, these can be safely ignored.

Examination

The examination of the lab consists of three parts. You are required to pass all three parts in order to get a passing grade on the lab.

1. Preparatory Quiz. This is quiz is done individually and covers the Preparatory Assignments. The preparatory assignments are all marked with Preparation in the lab manual and we recommend that you have your solutions to these assignments when you take the quiz. Deadline: 28 Feb. To pass you need 3/5 correct answers.
2. Summary Quiz. This quiz is done individually and covers the Summary section of the lab manual. Deadline: 28 Feb. To pass you need 3/5 correct answers.
3. A final 15-minute discussion session with a TA on Zoom. These are done in groups of three and are meant to summarize and discuss the results from the lab. The discussion will cover the Summary section in the lab manual. You can sign-up (Available from Wednesday 24 February) for the discussion sessions by going to the Calendar, clicking on "Find Appointment" to the right and selecting one of the available "Lab 3 Discussion Session" appointments. Sign-up Deadline: 28 Feb.

The slides that were used during some of the discussion sessions are now available here: Lab3questions.pdf, for repetition.

Matlab Files

You will need these Matlab files (compressed into a zip file) in order to do the lab. You can do the lab by simply following the steps in the lab manual.

The following gives a big picture of what you will be doing during the lab:

• In section 2 of the lab manual, you will get to know the process. By executing the define_process.m script (can be found in Matlab files folder), a linear model of the process will be defined (Don't change any parameters in this script). By this, the matrices A, B, C, D and the corresponding state-space model of the process, Gp, will be defined in Matlab workspace.
• Section 3 of the lab manual, introduces the performance specifications that the closed loop system has to meet.
• In sections 4-6 of the lab manual, you will be asked to design a controller that satisfies the performance specifications given in section 3.
• In the Matlab files folder, you will find some scripts (*.m files) and simulink models (*.mdl files): 
  • In section 4, you will be working with design1.m and model1.mdl files.
  • In section 5, you will be working with design2.m and model2.mdl files.
  • In section 6, you will be working with design3.m and model3.mdl files.
• In each of the sections 4-6, you need to follow the steps below in order to design a controller:
  1. Set the values for the parameters that are left undefined in the design files (design*.m files).
  2. Execute the design file (using the Run button on the EDITOR tab of Matlab or through the Command Window).
  3. Simulate the closed loop system by running the model*.mdl files. You need to open the *.mdl file and run it (either by pressing the Run button on the SIMULATION tab or by pressing <Ctrl>-T or <cmd>-T buttons on the keyboard).
  4. Check the specifications (The step response/control signal specifications can be checked by double clicking on the orange box "Plot against specifications"). 
  5. If the performance specifications are met, you are good to go and you can proceed to the next task. Otherwise, you need to go back to the step 1 and repeat the procedure above until the step response/control signal specifications are met.
• The lab will be concluded by summary questions.