Control systems lab introduction, hardware, software, and safety  (Page 2/3)

• Your derivation of the system's dynamic equations should be neat, easy to follow, and mathematically correct. In addition,remember to always draw a free-body diagram and label any system parameters and variables that will appear in yourderivation.
• The process you use to design your controller should be well outlined. In other words, don't just hand in your final design;show the steps you took to arrive at that design.
• Any LabVIEW VI that you write should be well organized and easy to follow (e.g. avoid crossing wires whenever possible).Remember, the diagram code should follow well from left to right. Furthermore, a neat and well organized VI will make the debuggingprocess easier for you should problems arise.
• When performing experiments in the lab, always record any important data that is acquired from the system; they may benecessary for calculations that you will need to perform later.
• Your answers to the post-lab questions should demonstrate that you fully understand all aspects of the experiment(s) you justperformed. Also, remember that with experimentation there is often no "right" answer. You should answer the question based on yourobservations and the results obtained from your particular system, which may be very different than somebody else's.

Program Debugging

Some students tend to think of the instructor as a program debugging aid. You should try diligently to find yourown errors before seeking assistance. Part of the objective of the computer assignments is to help you develop the ability to use thecomputer INDEPENDENTLY. You are not using the computer independently if someone else debugs your programs. You should onlyseek debugging assistance from the instructor if you have made a diligent effort to find your mistakes.

Lab hardware

The experiments for this course will be performed on plants from ECP (Educational Control Products), which will be controlled by a National Instruments PXI chassis equippedwith an embedded real-time controller and a reconfigurable multifunction I/O module.

Model 210 rectilinear plant

The ECP Model 210 Rectilinear Plant holds three mass carriages which can be loaded with brass weights andconnected in a variety of configurations using springs of varying stiffness. The adjustable dashpot can be used to provide dampingfor the system. A single drive motor provides actuation to the system via the first mass carriage, and position measurements aretaken by quadrature encoders.

Model 205 torsional plant

The ECP Model 205 Torsional Plant holds three disks each of which can be loaded with brass weights at varyingpositions. The disks are connected through their centers by thin rods giving the system rotational stiffness. A single driver motoractuates the system via the bottom disk, and quadrature encoders provide angular position measurements.

A-51 inverted pendulum accessory

The ECP A-51 Inverted Pendulum Accessory consists of a cylindrical weight attached to a slender rod. The position of the weight can be varied therefore changing the center of gravity of the assembly. The rod attaches to a low friction pivot joint whose angular position is measured by a quadrature encoder. The base plate allows for the accessory to be mounted on both the Model 210 and Model 205 plants.