Interactive Dynamics and Control (IDC)


IDC is the acronym for a group of applications designed to teach and reinforce basic system dynamics and control theory concepts. IDC was previously known as 'visdycon'.

The IDC software suite was developed for use in undergraduate mechanical engineering courses. It has been used in a number of graduate and undergraduate dynamics and controls courses at MIT. Binaries are available at ftp://lancet.mit.edu/pub/idc/.

What applications are available?
sysresp - system response
A playground for understanding linear system representations and methods for analyzing linear dynamic systems. Linear systems can be entered as transfer functions, root lists, poles & zeros, state-space matrices, linear graphs, or bond graphs. Once the system has been entered (a 1 to 30 second process), it can be analyzed using Bode plots, sinusoid, step, ramp, and impulse responses, s-plane, transfer function, and state space representations, and nyquist & nichols stability measures.
rlocus - root locus
A quick method of determining the root locus of a system. This program generates the root locus of a system based upon the roots entered in the s-plane. You can easily see the effects of small changes by dragging the roots of your system in the s-plane and watching the root locus change in real time. Rlocus also offers a step-by-step tutorial for interactively explaining how to derive a root locus.
lgraph - linear graph
System modelling via the linear graph method. You enter the system, lgraph derives the equations. This application uses the linear graph method to generate equations from a lumped parameter model. Lgraph gives you the equations in symbolic form as well as numeric, so you can easily see the effects of changes to the system parameters. Lgraph also offers a step-by-step, interactive tutorial for explaining how to derive the state equations from a linear graph.
How does one run the executables?
If you are running AFS, just run the program you want. The path is /afs/athena/course/other/visdycon/bin. If you are on an athena workstation, add the visdycon locker then type the name of the program you want to run. For example, to run sysresp you would do

add visdycon
sysresp &

You need do the 'add' part only once.

For more information...
We are in the process of converting the documentation to html.
For more details please direct your inquiries to idc@mit.edu
Please send bug reports to idc-bugs@mit.edu