6 bar or DR4B for the high cup

What is a better design choice?

  • 6 bar
  • DR4B
0 voters

Both 6 bar and DR4B lifts can hit high cup. This is poll is for a complex traybot with infeed rollers.

are you asking what people use, or what people think is the better option?

What is a better design choice?


May I suggest a catapult?


Ah so shoot once miss twice


what about a catapult

in my opinion neither of these is the best option.
a dr4b adds way too much complexity and weight that will likely jeopardize the competitiveness of the rest of the bot. I dabbled in n-bar arms earlier this season, a 6 bar isn’t really viable because you have to use long length beams for it to comfortably reach the center tower which doesn’t leave you much room to comfortably fit your intakes. an 8 bar is more viable, though I’ve learned that it’s very hard to brace an 8 bar well. you certainly can’t brace it behind the lift towers which means that you’ll have to tilt forward to let your lift go up, which means you can’t use a cube lock.

I think that if you really want a complex tray to reach the central tower than some sort of arm extenders would be your best bet. you could have your intakes on some custom slides allowing the arms to extend. then you could use some rubber bands and string to make the arms only extend when your lift goes way up.


the solution to that is having rollers that flip out downwards. it gives the arms extra length

Traybot with no endcap


or, do an 8 bar works for me

I just use my tray bot, and pop a cube out the back, it reaches the highest tower. But that does limit me to only scoring the highest tower and not descoring it.


that’s not enough to reach the high tower regardless, so it’s not really necessary

If you have a lot of driver practice, shooting cubes out of the back of a tray doesn’t take much longer than using an 8 bar or 6 bar to put a cube in the middle tower.


And with good alliance coordination and pre-planning, you can plan to drop a certain color into the tower as soon as you collect your first stack and unless the other team is able to descore, it will most likely stay there.

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The goal is to shave time from skills. Turning with a stack in the tray takes time as well as positioning every thing right. The most maneuverable robots have tray sliders so they don’t run into towers or their own stacks, so a backing to the top of the tray is quintessential.

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The six bar linkage can be moved up or down depending on what you want your tray angle to be, and the intakes flip out downwards to create the 10 inch total length and the 7.795 inch length of the intake without flaps. I will make a prototype soon to show that the idea works.

I didnt realise you meant on a 6 bar, I thought you meant on a normal traybot

What app did you use to test and illustrate this geometry?

I believe the program was titled ‘Linkage’. A quick search should get you the proper result

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