Our bot is a pretty heavy bot. We wanted to make the drive terrain faster so we implemented a 3:1 gear ratio in the base using 5 gears. The bot moves fast now, but the turning is super horrible. We are struggling to figure out why so. Please help! Sharing pics as attachment
Sorry, the gear ratio is 1:3. Motor is connected to the middle gear in the pictures. Any help is appreciated
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Maybe add a motor or something.
Thatās part of the tradeoff with a higher gear ratio like that; small motor movements means much bigger wheel movements. Our students tend to prefer a 1:2 (48 tooth to 24 tooth) ratio drivetrain, as it doesnāt sacrifice a bunch of power, and the speed is still adequate to get around the field and be controllable.
You can try to slow things down in code by multiplying the intended velocity by a decimal amount, like 0.6, which will cap you at 60% max speed. You could try to do more advanced things like linear acceleration in code.
Ultimately, almost everything in robotics (and especially in IQ) comes down to a tradeoff of pros and cons.
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Will try it out. Thanks so much for the helpš appreciate it!
If you are going for speed, 2wd might be better than 4wd.
Try just driving the traction wheels and not the omnis. Youāll get less loss through having less gears, and in turning your robot will pivot around the traction wheels, and the omnis will slide over the surface.
The higher you gear, the less you can afford any friction or other losses in your drivetrain.
Tried doing all of that. No luck. In facf powering just the traction wheel and not into a 4wd made it further bad 
the turnings got worse. I guess its the weight if the bot which is making it heavy for 2wd with gear ratio
switch to all omnis that will help
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From the looks of the picture, thereās some real opportunities to clean up the drivetrain. Those 3 shafts that extend through the āside plateā. Those all add friction and weight.
Check your shaft collars. Make sure they are not too tight against the plates/structural elements they are next to (friction).
Check your motor watts in code. Have it display to the brain. Compare it to free running watts (wheels lifted off the floor). Compare to a motor w/ nothing attached to it. In VRCā¦ a free running drivetrain should come in under 1/4 watt for reference.
Drop a pic of ENTIRE bot in here. Might be other areas to drop weight.
This is IQ, thatās not available.
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Oops. Isnāt there monitoring for some voltage level somewhere in iq?
You can monitor motor current, thatās all.
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You said your turns are āsuper horribleā and āfurther badā. Iām not sure we know what that means. Does it mean the turns are not smooth, or turns very slowly even when the joystick is at 100 to the left or right, or doesnāt turn on center of axis? Can you describe what horrible means so we can help? Maybe a video will help too because that may show exactly is going on.
The only thing I can see from your pictures is that you use 4 collars to prevent the shaft from sliding out of the motor. Collars have lots of friction, and when our team did IQ we simply used one collar to hold the shaft in place and sandwich it with spacers and washers to fill the gap and prevent it from sliding out. Spacers and washers have less friction.
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The turns are super slow. if the bot is running straight and then tries turning, it turns fine. But when the bot is resting and you want to turn it just moves super slowš
That will work. Whatās max current before built in limits apply?
We need better pictures from multiple angles and a copy of the code.
As some here have said, there are a few issues that are affecting your robotās ability to turn. One is that you are gearing 3:1, which means you are 3x as fast, but are sacrificing torque to 1/3. Torque and Speed are inverse, so you gain one over the expense of the other.
You said you have a heavy robot (donāt know exactly how heavy is heavy) but your drivetrain motors only have 1/3 of their torque, so naturally it will not have the same ability to push and turn.
On top of that, it looks like you have the motor in the center but driving 2 different wheel types. The Omnis have little to no friction in all directions, so they tend to turn better. However, you have traction wheels which have very high friction (especially going side to side movement), and will be difficult to turn (even when you have full torque). So, you have a weak motors trying to turn a heavy robot with one set of traction wheels. This can be the cause of your issue.
As others have suggested, you can switch to all omni wheels so there is little wheel friction when turning, or drop down to a 2:1 gear ratio to get back some of the torque, or move the motor closer to the traction wheels and cut down the number of gears since there is power transfer loss with each gear (so the more gears you have the less power makes its way to the wheel).
Hereās a very good picture of this.
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I think everyone has given your team some valid points they can consider. Before changing anything else, I would recommend your team to fill their robot with a full load of cubes and see how it drives straight and turns. I have a feeling that the robot will slowdown even more if the teamās robot is heavy to begin with. Yes reducing friction is important. But if the main issue is weight, the team might need to do a weight reduction on their robot. Switching 2x beams to 1x beams where possible, large plates to plastic sheets, etc can lighten the robot very quickly.
I hope that gives your kids a good starting point to solve some of the challenges. Cheers.
Thank you so much everyone. We implemented almost every feedback here and the bot is now super smooth in turns. We also reduced some weight.
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If this is 32 tooth to 8 tooth gears, and the 32 teeth gears are the input gears, then most likely even though the drivetrains speed is 4x fast, it has four times less torque (power) meaning that most likely your drivetrains lacks the need power.