Chassis can't support robot

My teams have tried building sturdier robots (Vex IQ) for Worlds, but the chassis buckles. Have any of you experienced this? If so, do you have any advice?

Better gear ratio, 2:1 is the best. That the standard drive-train ratio for every bot every year

You can try this drivetrain. Very quick and easy to build. Should give you enough rigidity to add your platform onto this drivetrain.

VEX IQ 839A FlexiDrive Build Tutorial - YouTube

I hope this helps. See you at worlds. Cheers.

Pictures always help


Thank you! We will keep plugging away!

Not sure how this is relevant to the question which is about the sturdiness of a chassis, not about the speed or gear ratio.

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As noted above, if you can share pictures this would help.
Bracing is the key part here. In the excellent Caution Tape video linked above, you can see that there is a single beam across the back linking the two haves of the chassis together and then an additional brace across the middle.

Consider where force is applied to your base. Without a picture, I’m guessing your weight is all supported by the center, so either add more 2x beams going across the base or move half of your structure to the outside of your wheel sandwiches.

Additionally, if the axels on which the wheels are placed are only connected to one point on the drivetrain instead of 2 on both sides, it could cause some serious sagging. If the upper part of your robot is heavy as well, then it will be too much weight for the drivetrain to bear. If your drivetrain isn’t connected from multiple connections sturdily, it might sag. You might also consider checking the quality of your motors. Lastly, make sure you have a speed gear ration instead of a torque gear ratio.
I hope this helps!