The vehicle model

To better predict the behavior of our Chevy Tahoe, a 3-D model of the vehicle has been (or "will be", depending on when your read this) created using Dymola.  Dymola is based on Modelica, an "object-oriented modeling language designed to allow convenient, component-oriented modeling of complex physical systems".

The CVS repository

To effectively organize, share, and update the models created in Dymola, a CVS file repository has been created in Dave van Gogh's CDS account.  CVS is a version-control system that keeps track of all revisions to files stored on the repository.  As a user, you "checkout" all of the files in the repository module to a local source (computer) that you have access to.  Among other things, you can then "add" files you've created to the repository or "commit" changes you've made to files you've downloaded to your working computer.  CVS keeps local copies of all revisions, who made the changes, and why the changes were made (via descriptions added by users).

If you'd like to access or upate models of the vehicle for use in either Dymola or Matlab-Simulink, here's what you need to do:

1. Send Dave and e-mail (dvangogh@caltech.edu) requesting a username and password.
2. Make current the directory in which you'd like to download your working copy of the CVS repository, and enter this command:
   
   cvs -d:pserver:username@cvs.cds.caltech.edu:/home/users/dvangogh/cvs_roots/gcroot login
   
   This logs you in to the "gcroot" repository in Dave's CDS account.
    
3. Enter the password.  If you requested a password within the past 12 hours or so, try again in a few hours.  If it still doesn't work after this time, contact Dave.
4. Checkout the module "gc" via this command:
   
   cvs -d:pserver:username@cvs.cds.caltech.edu:/home/users/dvangogh/cvs_roots/gcroot checkout gc
    
5. The directory structure and all files in the "gc" module of the "gcroot" repository should downloaded to a new directory called "gc".

Common CVS commands

NOTE:  To use the following commands:

1. you must be logged into the cvs repository (via step 2 above) and
2. your current directory must be .../gc (unless noted).

To UPDATE to the latest copies of files, enter the following command.  (Using the -dP option ensures you get the current directory structure [and not the old ones]):

cvs update -dP

To COMMIT changes you've made to files you've checked out, enter the following command (in the working directory that the file resides):

cvs commit [filename]

To ADD files to the repository, enter the following commands (in the working directory that the file resides):

cvs add [filename]
cvs commit [filename]

A full description of commands can be found here.  Another good source of CVS info is here.

Created by Dave van Gogh, 27 October 2003
Last updated 27 October 2003