How to build a fast and balanced drivetrain at the same time?

As you know, games like Tipping point requires being fast and being balanced at the same time besides power for success. But when we build robot fast, it becomes very out of balance because of the light mass. When we build it very strong and balanced, it becomes slow. How can i ensure both?

I thought that i need a drivetrain heavier than mobile goals, but that makes batteries die early and motors overheated/tired. So, it doesnt work for me.

Any suggestions? Thanks.

as you’ve discovered, speed and torque are inversely correlated. increasing one with the same motor quantity results in a decrease in the other. simply put, the only way to get more of both is to add more motors. 6 motor drive is very achievable and common in this game, which lets you have very high speeds and retain reasonable torque.

as for tipping and balance issues, try to focus weight reduction on thing higher up on the robot, so that the center of mass is lower. And try keeping the center of mass roughly central on the robot, so that it doesn’t want to tip forwards or backwards.

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We just had the goal as a counter weight. If you have the back hook, you can use a mobile goal. Just remember to make whatever grasps it VERY STRONG, because you can just pull the goal out.

With out drivetrain, to keep all the wheel straight, we have a 5xsomething panel, and we put bearings on it, because it is secured to the main body in 3 different points. I don’t have a picture and can’t get one until next Monday.

Try to have at least one preferably more brace the goes from edge to edge on top of any other bracing you want to add.

Also box the channels when you can.

With performance vehicles, weight is the enemy. Your question is about fast + balanced, so it seems like you don’t care about “able to shove other bots around”. With your constraints, adding weight is bad. If you want to resist other robots shoving you around, sometimes mass is good.

Start with physics. Why does a robot tip? It tips because the center of gravity is outside the wheelbase. Let’s say your robot is really light and you want to pick up something heavy. Must it tip? Not if you lift the object inside your wheelbase. Even with a heavy robot, a long lever on your lift can tilt your robot. Maybe your robot shouldn’t be a rectangle that picks up stuff outside of the rectangle? If your goal lift pulled it into your chassis, the weight of the goal would actually help balance your robot. (Note, there’s also a dynamic issue for fast starts and stops where the moment due to acceleration causes tipping. Again, the all motors in the bottom robots don’t notice this much.)

Where you put weight really matters, so you see teams with their battery and all their motors low on their base. They pay in complexity in moving power to where they need it, but those robots don’t have issues with tipping.

As a judge this season, I saw several teams counter-weighting their robots as it seems like you did. As a last ditch fix, sure, do what works. The down side is a sluggish robot that is hard to turn that eats batteries (and burns out motors).

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Try keeping the robot light, but mount motors, brain, and battery as centered and low down as possible. This will help a lot with balance issues.