I have one more question. When should you use aluminum channel vs steel channel for the drivetrain? Does it matter?
Use aluminum for everything. It is so much lighter and does not put as much stress on your motors. I like to just forget that steel exists. Please act like steel dosenât exist
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A simple tank drive is so much easier and better than almost every âspecialâ drive design. If you are worried about how to build a chassis I would assume that building the rest of the robot and driving /programming it would be another issue. So it would be extremely wise not to do some special drive. Also, almost all of the world champion teams use tank drives. They are just so much better.
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This was true in the V4 era, but in a defensive situation with V5, a steel drive base is your best friend.
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No, unless you need a 50 pound robot you should never ever use steel for your drive.
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Steel is stronger than aluminum. It would be preferable to use steel in places that need to stay structurally intact. Maybe you should use steel for the base and the lift towers but for the actual lift itself, aluminum would be the best option. Having a heavy base is not necessarily a bad thing. It makes your robot less âtipableâ and makes sure that your robot doesnât get damaged easily. But you should definitely use aluminum for structures that move, such as a lift.
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It matters quite a bit. I know in Turning Point I made a steel chassis to help with center of gravity and wheelie issues. It also helped with traction to win pushing matches so it has its place, however if you have a game with heavy game objects or where you are carrying lots of weight I would recommend aluminum to keep weight down as much as possible.
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At the very least, you need steel for cross supports on the drive. A bending drive base is a much worse problem than stalling after 15 minutes.
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What, using aluminum allows you to use the weight that would exist with steel to better support the drive. 10 out of 10 times a steel robot and an aluminum one that weight the same will show the aluminum drive being stronger as there is more bracing.
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If youâre using the smart config and trying to configure a drivetrain, you wonât be able to add the 5th wheel. Youâll have to just declare it as its own motor and use it manually.
yep, I know a couple of teams that used a mix of steel and aluminum on there drive base in tower takeover and it really helped with tipping because the steel can give you a lower center of gravity
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When should you use bigger wheels vs smaller wheels on a drivetrain?
Bigger wheels have DTs are faster than smaller wheel DTs, but smaller wheels have more torque
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Also different wheels have difference clearances. For climbing youâll want bigger wheels.
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Smaller wheels provide a lower CoG as well. In some cases Iâve seen people build taller lifts with smaller wheels (according to that team, they were able to use slightly longer bars on both levels of their dr4b which gave them more net height)
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What kind of drive are you using: tank or arcade?
Edit: And also send code pics.
Whatâs the difference between tank and arcade? Tank is where one joystick is one side (I think), but Iâm not sure about arcade.
If youâre using omni wheels, then you want to go with 4 inch omnis. They have the most traction of all of the omni wheels, and I havenât yet been in a case where 1:1 on 4 inch omnis with green internal motor cartridges wasnât enough torque for me.
Iâd like to address some of the things I have or have not seen concerning mecanum drives. They do lose a bit of speed compared to an identical omni drive. Mecanum drives excel at maneuvering around in tight spaces, but will fall behind in cases where strafing is ineffective and does not help it, such as open areas where an omni drive will be able to utilize its speed. However, mecanum drives are a very attractive option when paired with a heavy robot. The weight of the robot makes the mecanums more effective (because the greater weight means better traction which is vital for overcoming friction; all mecanum drives need to have some weight in order to function as indended). A heavy robot with an omni drive will be very cumbersome in tight spaces, whereas a heavy mecanum drive robot can still maneuver with ease.
Another note on mecanums and other holonomic drive types is that weight distribution becomes important, as a severe enough difference in traction between the front and back wheels will have adverse effects on strafing. It is also important that mecanums need a bit more force to turn.
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Tank drive assigns each joystick to its respective side of the drivetrain, so left stick controls the throttle of the left side, and so on. Split arcade is like most RC vehicles are controlled, one joystick controls throttle, the other joystick controls rotation. Full or true arcade is where a single joystick controls the entire robot. Most people are talking about split arcade when they say arcade.
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Tank uses both joysticks to control each side of the base. Arcade uses one joystick to control the robots forward, backward, and side to side movements(if you can strafe) and the other joystick controls turning.
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