Strategic Uses of Swerve Drive

[Jimmy Cao]

This is a discussion that my team has had every season for the last 3 seasons. The result has always been to build the swerve drive.

Really, it depends on the game. 2007 was Team 469's first time building a swerve drive. Why? We determined that we had the resources, and thought it would be somewhat helpful. It was a big challenge to undertake. Our first swerve drive design had numerous problems. Therefore, we designed and machined a 2nd iteration. Was it better? Yes. Was it still flawed? Very. We used 2 chains per module. Tensioning was a pain, and issues with chains jumping were big throughout the season. However, in the end, it was still successful.

Pros: Omnidirectional drive
Cons: Chains jumping, Wheels not holding up well to load (remember the AM wheels from 07?), Motor heavy (4xCIM + 2xFP + 2xGlobe), Difficult to program.

In '08, we again had the discussion about doing swerve. Well, in the end, we decided to do it again. Again, we decided to go for the full swerve (independent power/steering). It was quite resource heavy. However, we learned from the chain fiasco from the previous year. Using gears and a more "simplistic" design, made essentially of 3 CNC'd pieces, most of the mechanical/breakdown issues went away.

This last year, we again decided to go with swerve because mobility was deemed to be extremely important. As the base driver, I can comfortably say that the swerve drive provided huge benefits this year, from both an offensive and defensive standpoint. Might it be just as useful next year? I don't know.

However, swerve shouldn't be one of those things that you do automatically. Its not absolutely necessary to win. If executed well, it can provide a huge advantage, but at what cost? A simple 4/6 Wheel Drive system would use less motors (no steering), and almost definitely weigh less. The conventional drive systems eliminate the need for drive calibration and stuff. Some great teams have never built a swerve drive, such as 1114. Others, such as 217, have built it once. From what I hear, 217's experience with swerve was so bad that it's likely that they will never do it again.

Well I hope that provides some answers to your questions.