That's one of the problems that turned us away from the platform. It wasn't until last week (aaaah!) that we completely shifted designs. It's kind of a shame that we put 4 weeks of work into it.
The thing that played a large role in us abandoning the project was just that problem: side loads. Due to the holonomic nature of the platform, if the robot is pushed perpendicular to the the direction you're moving in, it can easily shift. The wheels were designed with that in mind (to be able to roll freely), but with another intention in mind (to be able to move holonomically).
Since we never actually managed to build our design, we haven't had the chance to try this out in real life. How well does the robot react to being pushed at 90 degree angles to its motion? (Just to validate a few concerns on our team.
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