This year it was my privilege to serve as one of the design judges at the California competition.
I did not have the opportunity to participate in FSAE in college but I do have the experience of designing, building and testing a complete car from scratch so I can closely relate to the many challenges faced by the teams.  Having now been a part of the judging process and having talked to and evaluated a number of teams I thought it might be helpful to provide some general feedback and input regarding the design portion of the competition, from my perspective, to all FSAE competitors.

It seems quite a few teams believe that showing up with a car which conforms to the rules and has some technically interesting bits and pieces is enough.  While that of course is a prerequisite, it is important to keep in mind that what you bring to the competition is not only the car but the entire team, the depth of team members' understanding of the design issues and process and the clarity of the design goals.  The car is a measure of how successful and consistent your design effort is at achieving those goals.

What you will see repeated several times in the following paragraphs is design justification.  The ability to show why and how a particular choice is made is very important both in the presentation and in creating a better car in the first place.

Based on what I saw in California, below are some of the key areas that I would advise each team to consider as you design and build your car and prepare for competition.

2. Design goals. Have a clear design goal for the entire car and be able to show how the choices made in the design and fabrication of each system support that goal.  The presentation for each system should reflect this.

3. Theory and analysis. Do the analysis and understand the theory. Be ready and able to reference and explain data to back up the analysis (more on that later). It is a perfectly valid choice to use something from last year if it works well, but you must understand WHY and HOW it works and be able to fully justify your choice to not redesign it. Bringing solid analysis of some alternatives you've considered is a good thing, especially for teams constrained by budget and/or time.

4. Reality checks and testing.  It is too easy to accidentally move a decimal point in calculations, mismatch units or mistake an assumption for fact.  Know the ballpark range of the result you’re expecting and check if the numbers make sense (this goes back to knowledge and understanding).  Verify critical parameters with physical testing.   Showing a correlation of actual versus predicted performance and being able to explain the discrepancies, if any, is very helpful – both in scoring and in building a better car.

5. Loads, properties of materials, stress and fatigue.  Be able to identify what the critical loads and load paths are.  Understand stiffness, shock loads, buckling, cyclical loads, fatigue and wear and how to account for each.  Know what a stress riser is and how it affects the strength of a part. When a weld is used on a material that relies on heat treat for strength, either show that the part was properly heat-treated afterwards or use annealed strength in your analysis (and be ready to justify the choice of material in the latter case!).  When a suspension arm tube is flattened at its end to attach to a bearing cup, understand the consequences to buckling strength and be ready to show the load analysis that takes it into account and justify why a different size tube wasn’t used instead.  Showing awareness of dissimilar metals corrosion is helpful, especially when it comes to use of carbon fiber.  In areas where strength depends on the process, like composites and bonded joints, have physical test results to verify performance and be ready to show that the process is sufficiently documented and consistently followed.

6. Optimization priorities.  Take care of the low-hanging fruit first.  A carbon suspension, a #10 suspension rodend or a hyper-alloy halfshaft are not impressive on a 600 lb steel-framed car.  Quite the contrary.  In fact it would take an extremely compelling analysis to make a #10 suspension rodend impressive under any circumstances.  Likewise internal engine modifications without proper analysis and execution of both intake and exhaust would call for very persuasive justification.

7. Communication.  Be sure other team members understand the key requirements and loads of your system, and that you understand theirs.  Communicate design changes that affect other systems to the corresponding team members.  When a team member graduates or leaves or is not able to attend the competition, make sure that at least someone else on the team has a full and thorough understanding of their work, including why and how choices were made. This is critical because the team will be expected to justify the design and saying 'that guy isn't here' will not help your presentation.

8. Promptness.  After all the effort and commitment to bring the car and the team to the competition, it would be very unfortunate to not be able to properly present your car because you are late to arrive or set up for judging or to lose points by filing a report late.

While at first glance some of the above may seem like a lot of extra work in addition to just getting the car built and ready, realize that the requirement for analysis and justification is aimed at making sure that design choices you make are informed ones.  Without a thorough understanding of the theory behind the design you are either constrained to using conservative and proven solutions which preclude innovation, or run a much greater than normal risk of creating things that are potentially dangerous.  This is true not only in this competition but in all of engineering.

What may help is to realize that the preliminary judging event is very limited in time.  In California, out of the 30 minutes allotted to each team the first 5 minutes were given to the team’s introductory presentation and the final 10 minutes are necessary for the judges to confer with each other and arrive at scores.  This leaves approximately 15 minutes for the interview portion of the judging (so be on time!). 

From this it should be obvious that justification does not entail reams and reams of printouts and charts – the judges are unlikely to have either the time or the inclination to dig through it. Your challenge is to concisely communicate to the judges the fundamentals behind your design, demonstrate your understanding of the theory and to show that you have in fact generated and analyzed the reams and reams of printouts and charts at some point in the design process. Just pointing at a thick notebook won’t do. Be aware that most judges are not easily dazzled and any technical term you use, you may be asked to explain in some detail.

The semi-final and final rounds of judging of course dig deeper and require more thorough answers but again in most cases it is your ability to intelligently speak on the subject that is going to impress the design judges, not the volume of data or the prettiness of pictures.  Pretty pictures do have marketing value even in design so don’t entirely discount them but don’t overestimate their importance either.

When it comes to design, the car sitting there is the best presentation tool you have – if you can point to a part, explain its features and characteristics and communicate clearly why it is this way and not some other way, you’re pretty much there.  Bring enough printouts to help make your point but make sure the point itself is a compelling one.  When asked for specific numbers, an approximation or a range will suffice in vast majority of cases and understanding the significance of the number is far more important than knowing it to ten digit precision.

If you find yourself in the final round of design judging, the car will have (hopefully) completed the dynamic events and its performance is a matter of record.  A team that does not take the opportunity to evaluate the design and its goals in the context of how it actually performed in competition (both high points and low) would be missing out.

The above is of course my personal view based on the experience of participating in judging of the design competition and I can’t speak for other judges you’ll encounter, but I hope you will find it helpful in both the design process and the competition itself.  FSAE is an excellent program and the real-world experience you’re getting puts you miles ahead of those who simply go through the regular engineering curriculum. So I want to encourage all the teams to continue learning, improving - and competing!

- Dennis Palatov
Palatov Motorsport
2009 FSAE West design judge

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