While the critterbot is moving around the pen, you might want time-stamped images capturing the robot's motion.  Run

> /var/critterlog/logger

and it will save one image per second into the current directory.  It will also save an img.log file where each line is a unix timestamp (seconds since 1970) followed by an image filename.  This is useful for aligning critterbot log files with the images.

You should be able to make movies with ffmpeg.  For example:

> ffmpeg -i img%09d.jpg -o critterbot-movie.mp4

There are additional options available for setting the frame rate for logging and for movies.