I have been using vex since 7th grade i am a junior now and having a massive problem with wheel squat which is making my robot steer left or right when trying to go straight I am using all shafts with my drive because the omni wheels i have and use do not have holes to screw to a gear directly so i can not use the screw joint i know how to do any ideas and comments would be appreciated thank you.
Can you provide a picture?
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Could you explain your problem better? I don’t understand what you’re trying to do and a “Wheel Squat”.
" I have been using vex since 7th grade i am a junior now and having a massive problem with wheel squat which is making my robot steer left or right when trying to go straight"
I can help you if you explain a bit more with your problem.
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I will be able to provide a picture tomorrow basically what is going on is that the robot is heavy enough to where the wheels end up being pushed down so then the bottom of the wheel is pushed out on the top of the wheel is pushed in giving it camber and it is unpredictable so the the robot does not drive straight
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Add some c channel to the top and the bottom of your frame between the two sides of your drivetrain. I have had the same problem in the past and it seems that beefing up the frame helps
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It sounds like the drivetrain has a lack of or very poor support. A picture would help a lot in diagnosing the cause.
a general rule of thumb when building a drivetrain is,
- Have at least 2 full cross braces, meaning they span the full width of the robot, outer c channel to outer c channel
- Use screwjoints on the wheels, not only do they not have the benefit of having lower friction than axle joints, when built right they also provide structure to the drivetrain, something even a well built axle shaft drivetrain cant provide
- try to stay at a reasonable weight, after a certain point, even well built drivetrains will begin to sag, so make sure your not pushing past 16 pounds, as after that point poor build quality will begin to show itself
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well i see the issue…
Dude you gotta have a c channel on the outside of the wheels aswell as the inside, its no wonder the robot is flexing, look on youtube or here on the forum on basic examples of quality drivetrains, @Xenon27 has some great examples of quality drivetrains you can look at.
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You have to add c channels on the other side of the wheel or it will bend as it only has one point of contact for the axles
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Use a c channel on the other side, then attach that c channel to the drivebase
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@ryleecooke If you look at all the well built robots a common recurring thing is bracing on both sides of the wheels as well as some form of bracing to keep the two sides of the drivetrain from bowing downward like what happened to your robot
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We did have bars on either side but with the size of our robot currently there was no easy way to connect the c channel to the rest of the robot but we are experimenting with other ways like possibly going over top of the wheels instead of at the end of the c channel to the other parts of our robot.
Also with the size of our wheels and gears that we have we are limited on our options.
Yeah that could work. I ended up having to add extra bracing to my robot towards the front but it goes up and over the front of my intake. It looks really goofy but if it works it works
Post of the day right there. Thanks for the pictures of all those double support frames.
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