3D Visualization of Multiple Variables

CS137 Assignment #3

1. Dates

2. Goals

1.      Learn about the complexities of translating your 2D gradients on to 3D.

2.      Identify and understand the perceptual and technical issues involved in 3D gradient visualization as compared to 2D gradients.

2.      Consider issues with transparency, visibility, color, and interaction with bat wing surface.

3.      Learn how new scientific and perceptual variables become important when a problem is in 3D.

3. Readings

·        Check the calendar page of the course's webpage for readings.
.      There are 2 books at the Cave that you may consult. As always, these books are not to leave the Cave room:

• The Miracle of Flight, by Dalton.
• Fundamentals of Aerodynamics, by Anderson.
  

.      Check out the websites from the LINKS section of the course website. Some of them relate to flight theory and have tons of examples and pictures.

.      Check out the bibliography in http://vis.cs.brown.edu/areas/projects/bat.html , http://vis.cs.brown.edu/areas/projects/artery.html , and http://vis.cs.brown.edu/resources/lists/flow.html . These are all technical papers related to flow visualization, but they represent the state of the art and might inspire some designs.

4. Assignment

4.1 Part A: 3D Wing and Flow Visualization

    Design a strategy for a single frame visualization of the interaction between a section of wing surface and surrounding air flow featuring pressure of flow (underside/topside), velocity and vorticity. With the help of the readings and the class lectures do the following:

• Pose a hypothesis of how the flow of air would move around the bat wing and make your visualization method work to validate that hypothesis.
  
• Utilizing the SAME visualization method, show an instance of flow around the wing where the initial hypothesis is NOT validated.
• Pose a new hypothesis based on that "discovery".

• Modify the original visualization method to validate this second hypothesis.
  

    This process mimics, in only two iterations, the process for designing visualizations and analyzing real scientific data. The handin for this first part of the assignment has to include these 3 points (optionaly 4), and you should be ready to explain each one of them in class on 10/16.

    Try to bring in your ideas from the 'Force and Form' assignment and explicitly target the interaction between air and wing. The 2D flow assignment should help you with what types of variables are part of a flow representation, how they are used and why they are important. If you have any other intuitive elements of the flow that you'd like to display, please do so, but be ready to explain why you think they are important and how they relate to the other variables. It's ok to come up with your own variable that captures some feature of the flow you think important. Chances are there's a scientific name for it already and Sharon might be able to explain what it is.

    For this part you can use hand drawing tools, three dimensional physical models, regular digital (2D or 3D) or CavePainting. Crits for this part will be in CIT 368 so, if you work in CavePainting, take snapshots of your work and print them out to bring them to class.

4.2 Part B: VR Implementation

    Put your design in CavePainting. You should use the 'frame-by-frame' feature of CavePainting to show your flow visualization move. We will make available to you a section of the bat wing in various positions along the wing beat. You can use these as reference for the form or you can make your own representation of the bat wing. You should include your legend in the 3D environment.

4.3 Other tasks

As part of each assignment, there will be a few questions that you should answer.  These can be found at the end of this handout and your answers should be emailed to the TAs (cs137tas@cs.brown.edu) by 9 AM (an hour before class starts) on Wednesday 10/25.  Most of these are very short questions intended to help guide you through the assignment.  They should not take long to answer.  Most of the time, a very brief, one sentence or less, answer is sufficient.

5. Questions (answer briefly)